Re: [time-nuts] minimalist sine to square
I wonder what the timing jitter is like. It may be useful to measure it along with its additive PN. Bruce > > On 22 January 2018 at 07:31 Robert LaJeunesse wrote: > > How about using a single 8-pin DIP IC that is under $2.50? The Microchip > MIC4422AYN "gate driver" takes a 3.3V signal in and produces a fast > rail-to-rail output swing, with a 4.5V to 18V supply range. Typical output > resistance is sub 1 Ohm, so not a problem driving a series back-terminated 50 > Ohm load. Note the 4422's rise and fall times are specified with a 10,000pF > load, given the primarily resistive load in this case the rise and fall > should be sub 10 ns (per p.5 of the data sheet). But do use beefy lo-Z traces > and hefty broadband supply bypassing, the MIC4422 can pump up to 9A into its > intended load. > > Bob L. > > > > > > Sent: Saturday, January 20, 2018 at 2:43 PM > > From: "Jerry Hancock" > > To: "Discussion of precise time and frequency measurement" > > > > Subject: Re: [time-nuts] minimalist sine to square > > > > ... > > > > Now that I had the input conditioned, I need to drive a 50ohm load > > with the signal coming from the PICDIV. Can someone point me at a circuit > > using transistors and 10V if possible? > > > > I am trying to duplicate one channel of the TADD2 so I can bring > > 10Mhz down to 10Khz. > > > > Thanks > > > > Jerry > > > > > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
How about using a single 8-pin DIP IC that is under $2.50? The Microchip MIC4422AYN "gate driver" takes a 3.3V signal in and produces a fast rail-to-rail output swing, with a 4.5V to 18V supply range. Typical output resistance is sub 1 Ohm, so not a problem driving a series back-terminated 50 Ohm load. Note the 4422's rise and fall times are specified with a 10,000pF load, given the primarily resistive load in this case the rise and fall should be sub 10 ns (per p.5 of the data sheet). But do use beefy lo-Z traces and hefty broadband supply bypassing, the MIC4422 can pump up to 9A into its intended load. Bob L. > Sent: Saturday, January 20, 2018 at 2:43 PM > From: "Jerry Hancock" > To: "Discussion of precise time and frequency measurement" > > Subject: Re: [time-nuts] minimalist sine to square > > ... > > Now that I had the input conditioned, I need to drive a 50ohm load with the > signal coming from the PICDIV. Can someone point me at a circuit using > transistors and 10V if possible? > > I am trying to duplicate one channel of the TADD2 so I can bring 10Mhz down > to 10Khz. > > Thanks > > Jerry ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
An npn emitter follower with collector connected to the 10V supply will produce a 4.2V swing in a 50 ohm load. However it only works well if reflections from the load are small. Otherwise, assuming that you want a 0-5V signal at the 50 ohm load its possible to build a back matched driver using 3 BJTs that will switch 200mA into a 25 ohm load with transition times around 5ns or so. Faster transition times require using transistors with ft's somewhat greater than 300MHz. However the 10V rail current increases to 200mA when the output is 5V at the 50 ohm load. Bruce > > On 21 January 2018 at 08:43 Jerry Hancock wrote: > > Tom might have started this as I was playing around with PICDIV and had > asked him the best conditioning circuit. Turned out I had all the parts to > copy the TADD-2 including the mini circuits transformer so that’s what I did. > It works well, pretty sensitive, etc. I’ve also used the bias trick with a > TTL or CMOS buffer when I needed to convert SPIDF signals to baseband for > driving an optical connection. > > Now that I had the input conditioned, I need to drive a 50ohm load with > the signal coming from the PICDIV. Can someone point me at a circuit using > transistors and 10V if possible? > > I am trying to duplicate one channel of the TADD2 so I can bring 10Mhz > down to 10Khz. > > Thanks > > Jerry > > > > > > On Jan 20, 2018, at 11:21 AM, Poul-Henning Kamp > > wrote: > > > > > > In message , > > jimlux writes: > > > > > > > > > > > > > > > > > > I played with that, I used a small transformer to > > > > balance the signal > > > > and then into LVDS receiver through a voltage divider. > > > > Worked well, > > > > but I didn't measure the jitter, it was just for a > > > > micro-controller. > > > > > > > > > > > > > > You can also do it with capacitive dc block to one side, and > > > some > > > resistors - the ap notes describe it. The receivers are a > > > fairly high Z > > > input, so you pick the voltage divider resistors to make the > > > termination > > > resistance right for the incoming signal. > > > > > > > > > > Yes, but that doesn't give you galvanic isolation, which I think is > > almost > > mandatory unless it is a metrology situation. > > > > -- > > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > > p...@freebsd.org | TCP/IP since RFC 956 > > FreeBSD committer | BSD since 4.3-tahoe > > Never attribute to malice what can adequately be explained by > > incompetence. > > > > ___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] minimalist sine to square
If you have a TADD2-mini you can just replace the divider chip with the 10 KHz version. That doesn't get you a 10 V output, though. -- > I am trying to duplicate one channel of the TADD2 so I can bring 10Mhz down > to 10Khz. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Tom might have started this as I was playing around with PICDIV and had asked him the best conditioning circuit. Turned out I had all the parts to copy the TADD-2 including the mini circuits transformer so that’s what I did. It works well, pretty sensitive, etc. I’ve also used the bias trick with a TTL or CMOS buffer when I needed to convert SPIDF signals to baseband for driving an optical connection. Now that I had the input conditioned, I need to drive a 50ohm load with the signal coming from the PICDIV. Can someone point me at a circuit using transistors and 10V if possible? I am trying to duplicate one channel of the TADD2 so I can bring 10Mhz down to 10Khz. Thanks Jerry > On Jan 20, 2018, at 11:21 AM, Poul-Henning Kamp wrote: > > > In message , jimlux > writes: > >>> I played with that, I used a small transformer to balance the signal >>> and then into LVDS receiver through a voltage divider. Worked well, >>> but I didn't measure the jitter, it was just for a micro-controller. >> >> You can also do it with capacitive dc block to one side, and some >> resistors - the ap notes describe it. The receivers are a fairly high Z >> input, so you pick the voltage divider resistors to make the termination >> resistance right for the incoming signal. > > Yes, but that doesn't give you galvanic isolation, which I think is almost > mandatory unless it is a metrology situation. > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > p...@freebsd.org | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by incompetence. > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
In message , jimlux writes: >> I played with that, I used a small transformer to balance the signal >> and then into LVDS receiver through a voltage divider. Worked well, >> but I didn't measure the jitter, it was just for a micro-controller. > >You can also do it with capacitive dc block to one side, and some >resistors - the ap notes describe it. The receivers are a fairly high Z >input, so you pick the voltage divider resistors to make the termination >resistance right for the incoming signal. Yes, but that doesn't give you galvanic isolation, which I think is almost mandatory unless it is a metrology situation. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Yes, I was just trying to see how far the circuit could be pushed (+27dBm input was still OK). With +13dBm input peak diode current without 100R and 330R resistors is about 20mA for the 3.3V circuit with an impedance step up from 50 to 400 ohm. My 100MHz Wenzel OCXO has an output of around +19dBm or so. I measure the output of all my sources before I connect them. Bruce > > On 20 January 2018 at 15:27 Bob kb8tq wrote: > > Hi > > My main point is that a +22 dbm (or even 16 dbm) OCXO is a *very* rare > item. If your > signal generator is set to +22 dbm … shame on you. If the part can do > well over +7 to > +13 dbm, that will cover the vast majority of the 10 MHz oscillators / > signal sources out there. > > Bob > > > > > > On Jan 19, 2018, at 8:51 PM, Bruce Griffiths > > wrote: > > > > Even the modern PICs spec 50mA max input currents. > > Simulation indicates 20mA peak diode currents without the 330 ohm > > resistors for a 2V pp input, even more for higher input signal levels. If > > one can guarantee that input is around 1V pp then the extra diodes and > > resistors aren't required. If its possible that an input of 16dBm or more > > may be used then the extra diodes and resistors are required. I simulated > > the circuit for inputs up to +22dBm. > > Current flowing in the IC protection diodes can degrade the timing > > jitter substantially (tens of picosec for HCMOS). > > > > Bruce > > > > > > > > > > On 20 January 2018 at 14:34 Bob kb8tq wrote: > > > > > > Hi > > > > > > Unless you really beat on the thing for days on end, you can > > > do without the 330 ohm and 100 ohm > > > resistors (along with the two diodes). Most modern gates have > > > pretty robust protection diodes. The > > > source impedance is high enough after the transform that the > > > available current is pretty low. On a > > > NC7SZ125 the negative diode is rated for 50 ma max and the > > > positive diode is rated for 20 ma > > > > > > Some math: > > > > > > If the two 1K’s properly terminate the circuit, you have a > > > 250 ohm source. (500 ohm load and 500 ohm > > > transformed from the sine input). A 1V overdrive (1/2 V + and > > > 1/2 V -) will put 2 ma into the diodes on the > > > peaks. The more likely case is that the negative is hit a bit > > > harder. The bias is most likely a bit below > > > 1/2 Vcc for best symmetry. > > > > > > None of this is to say you *should* hit the diodes. No matter > > > what sort they are, the performance will > > > degrade a bit when you do. How much is of course a “that > > > depends”. Most of us are not driving the > > > gate with a -180 dbc/Hz source and expecting -177 out of the > > > gate. > > > > > > Bob > > > > > > > > > > > > > > On Jan 19, 2018, at 8:14 PM, Bruce Griffiths > > > > wrote: > > > > > > > > Something like the attached circuit is suitable for > > > > driving the MCU clock input directly. > > > > The diodes should be schottky signal diodes like the > > > > 1N5711 series. The series resistors limit the diode peak current and > > > > the CLK input protection network current. It should work with inputs > > > > from 1V pp to 8Vpp. If SMT components were used it should all fit on a > > > > DIP compatible daughter board. > > > > > > > > Bruce > > > > > > > > > > > > > > > > > > On 20 January 2018 at 12:37 Bob kb8tq > > > > > wrote: > > > > > > > > > > Bob > > > > > > > > > > With a 1V p-p sort of output, a simple matching > > > > > network will get you into the 4 to 6V p-p range. > > > > > Drive that into a 5V compatible CMOS gate and > > > > > move on …. If you have a super hot output, put > > > > > a 3 db pad on it. > > > > > > > > > > Bob > > > > > > > > > > > > > > > > > > > > > > On Jan 19, 2018, at 5:40 PM, Tom Van Baak > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > Tom > > > > > > > What's the input signal amplitude? > > > > > > > What's the desired output signal (eg > > > > > > > 5V CMOS, 3.3V CMOS etc)? > > > > > > > Bruce > > > > > > > > > > > > > > > > > > > > > > > > > > It's for a typical 5 or 10 MHz OCXO / Rb / > > > > > > Cs with sinewave output; say, 1 Vpp. The output should be 3.3 or 5 > > > > > > V depending on what the MCU needs. It doesn't have to have stunnin
Re: [time-nuts] minimalist sine to square
Hi My main point is that a +22 dbm (or even 16 dbm) OCXO is a *very* rare item. If your signal generator is set to +22 dbm … shame on you. If the part can do well over +7 to +13 dbm, that will cover the vast majority of the 10 MHz oscillators / signal sources out there. Bob > On Jan 19, 2018, at 8:51 PM, Bruce Griffiths > wrote: > > Even the modern PICs spec 50mA max input currents. > Simulation indicates 20mA peak diode currents without the 330 ohm resistors > for a 2V pp input, even more for higher input signal levels. If one can > guarantee that input is around 1V pp then the extra diodes and resistors > aren't required. If its possible that an input of 16dBm or more may be used > then the extra diodes and resistors are required. I simulated the circuit for > inputs up to +22dBm. > Current flowing in the IC protection diodes can degrade the timing jitter > substantially (tens of picosec for HCMOS). > > Bruce >> On 20 January 2018 at 14:34 Bob kb8tq wrote: >> >> >> Hi >> >> Unless you really beat on the thing for days on end, you can do without the >> 330 ohm and 100 ohm >> resistors (along with the two diodes). Most modern gates have pretty robust >> protection diodes. The >> source impedance is high enough after the transform that the available >> current is pretty low. On a >> NC7SZ125 the negative diode is rated for 50 ma max and the positive diode is >> rated for 20 ma >> >> Some math: >> >> If the two 1K’s properly terminate the circuit, you have a 250 ohm source. >> (500 ohm load and 500 ohm >> transformed from the sine input). A 1V overdrive (1/2 V + and 1/2 V -) will >> put 2 ma into the diodes on the >> peaks. The more likely case is that the negative is hit a bit harder. The >> bias is most likely a bit below >> 1/2 Vcc for best symmetry. >> >> None of this is to say you *should* hit the diodes. No matter what sort they >> are, the performance will >> degrade a bit when you do. How much is of course a “that depends”. Most of >> us are not driving the >> gate with a -180 dbc/Hz source and expecting -177 out of the gate. >> >> Bob >> >>> On Jan 19, 2018, at 8:14 PM, Bruce Griffiths >>> wrote: >>> >>> Something like the attached circuit is suitable for driving the MCU clock >>> input directly. >>> The diodes should be schottky signal diodes like the 1N5711 series. The >>> series resistors limit the diode peak current and the CLK input protection >>> network current. It should work with inputs from 1V pp to 8Vpp. If SMT >>> components were used it should all fit on a DIP compatible daughter board. >>> >>> Bruce On 20 January 2018 at 12:37 Bob kb8tq wrote: Bob With a 1V p-p sort of output, a simple matching network will get you into the 4 to 6V p-p range. Drive that into a 5V compatible CMOS gate and move on …. If you have a super hot output, put a 3 db pad on it. Bob > On Jan 19, 2018, at 5:40 PM, Tom Van Baak wrote: > >> Tom >> What's the input signal amplitude? >> What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? >> Bruce > > It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave output; say, > 1 Vpp. The output should be 3.3 or 5 V depending on what the MCU needs. > It doesn't have to have stunning performance: think breadboard, PIC, > Arduino sort of stuff. I was looking for something in a PDIP-8 package; > the same as all the picDIV or picPET chips I use. That's why older parts > like µA9637 / DS9637 came to mind. > > /tvb > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. >>> >> ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Even the modern PICs spec 50mA max input currents. Simulation indicates 20mA peak diode currents without the 330 ohm resistors for a 2V pp input, even more for higher input signal levels. If one can guarantee that input is around 1V pp then the extra diodes and resistors aren't required. If its possible that an input of 16dBm or more may be used then the extra diodes and resistors are required. I simulated the circuit for inputs up to +22dBm. Current flowing in the IC protection diodes can degrade the timing jitter substantially (tens of picosec for HCMOS). Bruce > On 20 January 2018 at 14:34 Bob kb8tq wrote: > > > Hi > > Unless you really beat on the thing for days on end, you can do without the > 330 ohm and 100 ohm > resistors (along with the two diodes). Most modern gates have pretty robust > protection diodes. The > source impedance is high enough after the transform that the available > current is pretty low. On a > NC7SZ125 the negative diode is rated for 50 ma max and the positive diode is > rated for 20 ma > > Some math: > > If the two 1K’s properly terminate the circuit, you have a 250 ohm source. > (500 ohm load and 500 ohm > transformed from the sine input). A 1V overdrive (1/2 V + and 1/2 V -) will > put 2 ma into the diodes on the > peaks. The more likely case is that the negative is hit a bit harder. The > bias is most likely a bit below > 1/2 Vcc for best symmetry. > > None of this is to say you *should* hit the diodes. No matter what sort they > are, the performance will > degrade a bit when you do. How much is of course a “that depends”. Most of us > are not driving the > gate with a -180 dbc/Hz source and expecting -177 out of the gate. > > Bob > > > On Jan 19, 2018, at 8:14 PM, Bruce Griffiths > > wrote: > > > > Something like the attached circuit is suitable for driving the MCU clock > > input directly. > > The diodes should be schottky signal diodes like the 1N5711 series. The > > series resistors limit the diode peak current and the CLK input protection > > network current. It should work with inputs from 1V pp to 8Vpp. If SMT > > components were used it should all fit on a DIP compatible daughter board. > > > > Bruce > >> On 20 January 2018 at 12:37 Bob kb8tq wrote: > >> > >> > >> Bob > >> > >> With a 1V p-p sort of output, a simple matching network will get you into > >> the 4 to 6V p-p range. > >> Drive that into a 5V compatible CMOS gate and move on …. If you have a > >> super hot output, put > >> a 3 db pad on it. > >> > >> Bob > >> > >>> On Jan 19, 2018, at 5:40 PM, Tom Van Baak wrote: > >>> > Tom > What's the input signal amplitude? > What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? > Bruce > >>> > >>> It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave output; say, > >>> 1 Vpp. The output should be 3.3 or 5 V depending on what the MCU needs. > >>> It doesn't have to have stunning performance: think breadboard, PIC, > >>> Arduino sort of stuff. I was looking for something in a PDIP-8 package; > >>> the same as all the picDIV or picPET chips I use. That's why older parts > >>> like µA9637 / DS9637 came to mind. > >>> > >>> /tvb > >>> > >>> ___ > >>> time-nuts mailing list -- time-nuts@febo.com > >>> To unsubscribe, go to > >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >>> and follow the instructions there. > >> > >> ___ > >> time-nuts mailing list -- time-nuts@febo.com > >> To unsubscribe, go to > >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > > > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
That network was for a 10MHz input. For 5MHz double the L and C values. For 3.3V one could use a lower step up say from 50 to 400 ohms rather than from 50 to 800 ohms. 1uH and 150pF and change 1k6 resistors to 820R. Swap the 5V supply for a 3.3V supply. L and C values aren't critical 5% or somewhat looser tolerance should be suffice. Bruce > > On 20 January 2018 at 14:14 Bruce Griffiths > wrote: > > Something like the attached circuit is suitable for driving the MCU clock > input directly. > The diodes should be schottky signal diodes like the 1N5711 series. The > series resistors limit the diode peak current and the CLK input protection > network current. It should work with inputs from 1V pp to 8Vpp. If SMT > components were used it should all fit on a DIP compatible daughter board. > > Bruce > > > > > > On 20 January 2018 at 12:37 Bob kb8tq wrote: > > > > Bob > > > > With a 1V p-p sort of output, a simple matching network will get > > you into the 4 to 6V p-p range. > > Drive that into a 5V compatible CMOS gate and move on …. If you > > have a super hot output, put > > a 3 db pad on it. > > > > Bob > > > > > > > > > > On Jan 19, 2018, at 5:40 PM, Tom Van Baak > > > wrote: > > > > > > > > > > > > > > Tom > > > > What's the input signal amplitude? > > > > What's the desired output signal (eg 5V CMOS, 3.3V CMOS > > > > etc)? > > > > Bruce > > > > > > > > > > > > > > It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave > > > output; say, 1 Vpp. The output should be 3.3 or 5 V depending on what the > > > MCU needs. It doesn't have to have stunning performance: think > > > breadboard, PIC, Arduino sort of stuff. I was looking for something in a > > > PDIP-8 package; the same as all the picDIV or picPET chips I use. That's > > > why older parts like µA9637 / DS9637 came to mind. > > > > > > /tvb > > > > > > ___ > > > time-nuts mailing list -- time-nuts@febo.com > > > To unsubscribe, go to > > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > and follow the instructions there. > > > > > > > > > > ___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions > > there.___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > > > > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Hi Unless you really beat on the thing for days on end, you can do without the 330 ohm and 100 ohm resistors (along with the two diodes). Most modern gates have pretty robust protection diodes. The source impedance is high enough after the transform that the available current is pretty low. On a NC7SZ125 the negative diode is rated for 50 ma max and the positive diode is rated for 20 ma Some math: If the two 1K’s properly terminate the circuit, you have a 250 ohm source. (500 ohm load and 500 ohm transformed from the sine input). A 1V overdrive (1/2 V + and 1/2 V -) will put 2 ma into the diodes on the peaks. The more likely case is that the negative is hit a bit harder. The bias is most likely a bit below 1/2 Vcc for best symmetry. None of this is to say you *should* hit the diodes. No matter what sort they are, the performance will degrade a bit when you do. How much is of course a “that depends”. Most of us are not driving the gate with a -180 dbc/Hz source and expecting -177 out of the gate. Bob > On Jan 19, 2018, at 8:14 PM, Bruce Griffiths > wrote: > > Something like the attached circuit is suitable for driving the MCU clock > input directly. > The diodes should be schottky signal diodes like the 1N5711 series. The > series resistors limit the diode peak current and the CLK input protection > network current. It should work with inputs from 1V pp to 8Vpp. If SMT > components were used it should all fit on a DIP compatible daughter board. > > Bruce >> On 20 January 2018 at 12:37 Bob kb8tq wrote: >> >> >> Bob >> >> With a 1V p-p sort of output, a simple matching network will get you into >> the 4 to 6V p-p range. >> Drive that into a 5V compatible CMOS gate and move on …. If you have a super >> hot output, put >> a 3 db pad on it. >> >> Bob >> >>> On Jan 19, 2018, at 5:40 PM, Tom Van Baak wrote: >>> Tom What's the input signal amplitude? What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? Bruce >>> >>> It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave output; say, 1 >>> Vpp. The output should be 3.3 or 5 V depending on what the MCU needs. It >>> doesn't have to have stunning performance: think breadboard, PIC, Arduino >>> sort of stuff. I was looking for something in a PDIP-8 package; the same as >>> all the picDIV or picPET chips I use. That's why older parts like µA9637 / >>> DS9637 came to mind. >>> >>> /tvb >>> >>> ___ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >> >> ___ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] minimalist sine to square
Tom, Hook the 53132A calibrator that I sent you and check one of the calibrator outputs for signal goodness. It uses the sine-square circuit in the LPRO-101 manual (input cap connected to center of a 39K/39K voltage divider connected to a 74HC gate (74AC gates have some advantages and disadvantages here).It's the simplest excellent bang-for-the buck squarer (three passives and a single CMOS gate). You can use single-gate chips. I'm using the same circuit on the LPFRS/LPRO/OCXO interface board. I'm also pondering doing a small board with a sine/square wave input, square wave output, PICDIV, PICPET, and a 10 MHz square to sine filter. Attached is the xDEV plot of the calibrator (using TAPR-TICC, TADD2-mini, 5071A reference).___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Something like the attached circuit is suitable for driving the MCU clock input directly. The diodes should be schottky signal diodes like the 1N5711 series. The series resistors limit the diode peak current and the CLK input protection network current. It should work with inputs from 1V pp to 8Vpp. If SMT components were used it should all fit on a DIP compatible daughter board. Bruce > On 20 January 2018 at 12:37 Bob kb8tq wrote: > > > Bob > > With a 1V p-p sort of output, a simple matching network will get you into the > 4 to 6V p-p range. > Drive that into a 5V compatible CMOS gate and move on …. If you have a super > hot output, put > a 3 db pad on it. > > Bob > > > On Jan 19, 2018, at 5:40 PM, Tom Van Baak wrote: > > > >> Tom > >> What's the input signal amplitude? > >> What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? > >> Bruce > > > > It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave output; say, 1 > > Vpp. The output should be 3.3 or 5 V depending on what the MCU needs. It > > doesn't have to have stunning performance: think breadboard, PIC, Arduino > > sort of stuff. I was looking for something in a PDIP-8 package; the same as > > all the picDIV or picPET chips I use. That's why older parts like µA9637 / > > DS9637 came to mind. > > > > /tvb > > > > ___ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] minimalist sine to square
The Efratom/Tektronix PTB-100 took the 10Mhz sine out of the FRK brick, AC coupled it to the input of an 74LS14 biased with a votage divider from +5 to ground. 4 parts! Cheers, Corby ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Bob With a 1V p-p sort of output, a simple matching network will get you into the 4 to 6V p-p range. Drive that into a 5V compatible CMOS gate and move on …. If you have a super hot output, put a 3 db pad on it. Bob > On Jan 19, 2018, at 5:40 PM, Tom Van Baak wrote: > >> Tom >> What's the input signal amplitude? >> What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? >> Bruce > > It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave output; say, 1 > Vpp. The output should be 3.3 or 5 V depending on what the MCU needs. It > doesn't have to have stunning performance: think breadboard, PIC, Arduino > sort of stuff. I was looking for something in a PDIP-8 package; the same as > all the picDIV or picPET chips I use. That's why older parts like µA9637 / > DS9637 came to mind. > > /tvb > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
A fast DIP comparator such as an LT1016 should work but it won't perform well without an effective ground plane. If a CMOS gate is used then a low Q LC impedance step up network or equivalent will be needed to increase the signal swing at the gate input. Add a couple of schottky diode clamps for overvoltage clamping (internal CMOS gate clamp devices usually degrade performance if they conduct). Bruce > > On 20 January 2018 at 11:40 Tom Van Baak wrote: > > > > > > Tom > > What's the input signal amplitude? > > What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? > > Bruce > > > > > > It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave output; say, > 1 Vpp. The output should be 3.3 or 5 V depending on what the MCU needs. It > doesn't have to have stunning performance: think breadboard, PIC, Arduino > sort of stuff. I was looking for something in a PDIP-8 package; the same as > all the picDIV or picPET chips I use. That's why older parts like µA9637 / > DS9637 came to mind. > > /tvb > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Now, if one added an optional TTL threshold 5V CMOS single gate inverter/buffer to produce 5V output when required and added an SMT 5V->3.3V regulator and mounted it all on a small PCB with pins to make it DIP compatible that would meet the brief and then some. Otherwise an SMT (not many DIP ones left) comparator mounted on a DIP/SMT converter board would also work albeit with a PN/jitter performance penalty. Bruce > On 20 January 2018 at 11:37 Gerhard Hoffmann wrote: > > > > > Am 19.01.2018 um 20:31 schrieb Tom Van Baak: > > John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It > > performs very well but requires +10 V. > > > > I'm looking for a solution that works at 5 V (e.g., USB powered) and also > > uses fewer parts. Wenzel also mentions using a differential line receiver > > [2]. That would be an ideal single-chip 5 V solution for me but the two > > parts he mentions, MC1489 [3] and SN55182 [4], don't appear fast enough for > > a 10 MHz input. > > > > Can any of you circuit experts suggest some line receivers that would work? > > Maybe DS9637 [5]? This isn't for cesium work so it doesn't have to be quite > > as good as the TADD-2. > < http://cds.linear.com/docs/en/datasheet/6957fb.pdf > > < http://cds.linear.com/docs/en/design-note/dn514f.pdf > > > I have used it, found no problems. It is somewhat small :-) > > regards, Gerhard > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
> Tom > What's the input signal amplitude? > What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? > Bruce It's for a typical 5 or 10 MHz OCXO / Rb / Cs with sinewave output; say, 1 Vpp. The output should be 3.3 or 5 V depending on what the MCU needs. It doesn't have to have stunning performance: think breadboard, PIC, Arduino sort of stuff. I was looking for something in a PDIP-8 package; the same as all the picDIV or picPET chips I use. That's why older parts like µA9637 / DS9637 came to mind. /tvb ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Am 19.01.2018 um 20:31 schrieb Tom Van Baak: John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I'm looking for a solution that works at 5 V (e.g., USB powered) and also uses fewer parts. Wenzel also mentions using a differential line receiver [2]. That would be an ideal single-chip 5 V solution for me but the two parts he mentions, MC1489 [3] and SN55182 [4], don't appear fast enough for a 10 MHz input. Can any of you circuit experts suggest some line receivers that would work? Maybe DS9637 [5]? This isn't for cesium work so it doesn't have to be quite as good as the TADD-2. < http://cds.linear.com/docs/en/datasheet/6957fb.pdf > < http://cds.linear.com/docs/en/design-note/dn514f.pdf > I have used it, found no problems. It is somewhat small :-) regards, Gerhard ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Tom What's the input signal amplitude? What's the desired output signal (eg 5V CMOS, 3.3V CMOS etc)? Bruce > On 20 January 2018 at 08:31 Tom Van Baak wrote: > > > John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs > very well but requires +10 V. > > I'm looking for a solution that works at 5 V (e.g., USB powered) and also > uses fewer parts. Wenzel also mentions using a differential line receiver > [2]. That would be an ideal single-chip 5 V solution for me but the two parts > he mentions, MC1489 [3] and SN55182 [4], don't appear fast enough for a 10 > MHz input. > > Can any of you circuit experts suggest some line receivers that would work? > Maybe DS9637 [5]? This isn't for cesium work so it doesn't have to be quite > as good as the TADD-2. > > Thanks, > /tvb > > [1] http://www.tapr.org/~n8ur/T2_Mini_Manual.pdf > [2] http://www.wenzel.com/documents/waveform.html > [3] https://www.onsemi.com/pub/Collateral/MC1489-D.PDF > [4] http://www.ti.com/lit/ds/slls092d/slls092d.pdf > [5] http://www.ti.com/lit/ds/symlink/ds9637a.pdf > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
SN65LVDS34D --- Graham / KE9H == On Fri, Jan 19, 2018 at 3:45 PM, Vlad wrote: > > > On 2018-01-19 14:31, Tom Van Baak wrote: > >> John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It >> performs very well but requires +10 V. >> > > > I am using Wenzel approach without modification to drive it from +5V. I > didn't see any issues for my applications (usually it perform > sine-to-square conversion from OCXO to feed MCU clock). > > > -- > WBW, > > V.P. > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/m > ailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
On 2018-01-19 14:31, Tom Van Baak wrote: John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I am using Wenzel approach without modification to drive it from +5V. I didn't see any issues for my applications (usually it perform sine-to-square conversion from OCXO to feed MCU clock). -- WBW, V.P. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
On 1/19/18 12:54 PM, Poul-Henning Kamp wrote: In message <898171c2-0e9a-6a2a-dcfc-b7d893f89...@earthlink.net>, jimlux writes: What about the plethora of LVDS receivers - they're basically a differential input thresholder, with deliberate hysteresis, looking for a 300 mV shift across a 100 ohm resistor. I played with that, I used a small transformer to balance the signal and then into LVDS receiver through a voltage divider. Worked well, but I didn't measure the jitter, it was just for a micro-controller. You can also do it with capacitive dc block to one side, and some resistors - the ap notes describe it. The receivers are a fairly high Z input, so you pick the voltage divider resistors to make the termination resistance right for the incoming signal. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
In message <63ae173b-93f4-ffe4-ddf1-655761665...@earthlink.net>, jimlux writes: >On 1/19/18 11:31 AM, Tom Van Baak wrote: >You do want to watch the common mode voltages - some of the parts are >not good about having the signals swing near the rails (or beyond). Also be aware that specs are for balanced input signals, if you tie one of the inputs to a threshold voltage, published specs may not apply, in particular speed. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
In message <898171c2-0e9a-6a2a-dcfc-b7d893f89...@earthlink.net>, jimlux writes: >What about the plethora of LVDS receivers - they're basically a >differential input thresholder, with deliberate hysteresis, looking for >a 300 mV shift across a 100 ohm resistor. I played with that, I used a small transformer to balance the signal and then into LVDS receiver through a voltage divider. Worked well, but I didn't measure the jitter, it was just for a micro-controller. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
Tom, I recently built such a device using a couple of stages of a 74HC04, with the RF input to the 1st stage AC coupled and the input biased by a high-value (a couple of megohms) resistor feeding back from the output of the first inverter stage to the input of that stage. It's so dirt simple, it's hard to beat. I was not particularly concerned about jitter, so if you're not already familiar enough with the circuit to know whether or not it's good enough, it might be worth a try. BTW, I am running at 10 MHz from a PRS-10 Rb, and just wanted something to drive a count-down chain. And there's always the 74AC04 if you wanted faster edges. Dana Whitlow On Fri, Jan 19, 2018 at 1:31 PM, Tom Van Baak wrote: > John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It > performs very well but requires +10 V. > > I'm looking for a solution that works at 5 V (e.g., USB powered) and also > uses fewer parts. Wenzel also mentions using a differential line receiver > [2]. That would be an ideal single-chip 5 V solution for me but the two > parts he mentions, MC1489 [3] and SN55182 [4], don't appear fast enough for > a 10 MHz input. > > Can any of you circuit experts suggest some line receivers that would > work? Maybe DS9637 [5]? This isn't for cesium work so it doesn't have to be > quite as good as the TADD-2. > > Thanks, > /tvb > > [1] http://www.tapr.org/~n8ur/T2_Mini_Manual.pdf > [2] http://www.wenzel.com/documents/waveform.html > [3] https://www.onsemi.com/pub/Collateral/MC1489-D.PDF > [4] http://www.ti.com/lit/ds/slls092d/slls092d.pdf > [5] http://www.ti.com/lit/ds/symlink/ds9637a.pdf > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/ > mailman/listinfo/time-nuts > and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
On 1/19/18 11:31 AM, Tom Van Baak wrote: John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I'm looking for a solution that works at 5 V (e.g., USB powered) and also uses fewer parts. Wenzel also mentions using a differential line receiver [2]. That would be an ideal single-chip 5 V solution for me but the two parts he mentions, MC1489 [3] and SN55182 [4], don't appear fast enough for a 10 MHz input. There are tons of LVDS that run on 3.3 or 5V, Maxim, TI both have parts. The first Maxim part google turned up with "LVDS receiver" was a quad, esd protected unit good to 400 MHz, 2ns prop delay, 50mV hysteresis. You do want to watch the common mode voltages - some of the parts are not good about having the signals swing near the rails (or beyond). ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] minimalist sine to square
On 1/19/18 11:31 AM, Tom Van Baak wrote: John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I'm looking for a solution that works at 5 V (e.g., USB powered) and also uses fewer parts. Wenzel also mentions using a differential line receiver [2]. That would be an ideal single-chip 5 V solution for me but the two parts he mentions, MC1489 [3] and SN55182 [4], don't appear fast enough for a 10 MHz input. Can any of you circuit experts suggest some line receivers that would work? Maybe DS9637 [5]? This isn't for cesium work so it doesn't have to be quite as good as the TADD-2. What about the plethora of LVDS receivers - they're basically a differential input thresholder, with deliberate hysteresis, looking for a 300 mV shift across a 100 ohm resistor. Plenty fast (GHz) Thanks, /tvb [1] http://www.tapr.org/~n8ur/T2_Mini_Manual.pdf [2] http://www.wenzel.com/documents/waveform.html [3] https://www.onsemi.com/pub/Collateral/MC1489-D.PDF [4] http://www.ti.com/lit/ds/slls092d/slls092d.pdf [5] http://www.ti.com/lit/ds/symlink/ds9637a.pdf ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] minimalist sine to square
John's TADD-2-mini [1] uses the Wenzel sine-to-square converter. It performs very well but requires +10 V. I'm looking for a solution that works at 5 V (e.g., USB powered) and also uses fewer parts. Wenzel also mentions using a differential line receiver [2]. That would be an ideal single-chip 5 V solution for me but the two parts he mentions, MC1489 [3] and SN55182 [4], don't appear fast enough for a 10 MHz input. Can any of you circuit experts suggest some line receivers that would work? Maybe DS9637 [5]? This isn't for cesium work so it doesn't have to be quite as good as the TADD-2. Thanks, /tvb [1] http://www.tapr.org/~n8ur/T2_Mini_Manual.pdf [2] http://www.wenzel.com/documents/waveform.html [3] https://www.onsemi.com/pub/Collateral/MC1489-D.PDF [4] http://www.ti.com/lit/ds/slls092d/slls092d.pdf [5] http://www.ti.com/lit/ds/symlink/ds9637a.pdf ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
