Re: [time-nuts] Power Supply for AD9852 / AD9854
On Sat, Mar 15, 2014 at 9:21 PM, d0ct0r t...@patoka.org wrote: Many thanks indeed for detailed answer ! Yes, I will using Evaluation Board for my project. Then it is already done for you. They have added all the bypass caps already on the board. Not much left for you to do. In fact you can't do anything because all the important design work happens within millimeters of the power and ground pins. -- Chris Albertson Redondo Beach, California ___ 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] Power Supply for AD9852 / AD9854
For inspiration you can look on this design we use for many purposes, the design was mainly a beacon exciter but is now also used in many laboratories in the developing of laser controlled freq. standards (1x10-18) and also as a direct programmable freq. source with milli Herz resolution locked to a 10 MHz std. http://rudius.net/oz2m/ngnb/dds.htm In the bottom of the web page is diagrams of both power supply and DDS design, the DDS is controlled by an ATMEGA 128A, all is open source. // Michael, OZ2ELA -Oprindelig meddelelse- Fra: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] På vegne af d0ct0r Sendt: 16. marts 2014 05:22 Til: time-nuts@febo.com Emne: Re: [time-nuts] Power Supply for AD9852 / AD9854 Many thanks indeed for detailed answer ! Yes, I will using Evaluation Board for my project. Regards, V.P. On 2014-03-16 00:06, Charles Steinmetz wrote: By design, DDS stones like AD9852 from Analog Devices, required separated power lines for AVDD, DVDD and VCC. What will is simple solution for that ? I am planing to use following approach: +5V from linear PS, then three LC filters, then three 3.3V voltage regulators (Ex.: MC33269T) connected to each filter. Is it good enough ? May be its better solution for this ? Or may be that could be simplified to join AVDD and VCC (AVDD will be connected to VCC via 100 Ohm). Do you have the AD evaluation board, or are you starting with the bare chip? If you really want to know how simple you can make it, why not try it yourself, and see what you need? You will learn a lot more that way than by asking first every time a question occurs to you. Follow the evaluation board plan and put a 0.1uF (100nF) monolithic ceramic capacitor right at each power input pin of the IC itself (something like 10 capacitors per supply). First, use one 3.3v regulator and feed its output straight to all three circuits, with simply a local bypass cap for each one (plus the per-pin capacitors as noted above). Run the DDS and see how it performs. Then, see how three separate LC filters perform (each LC fed by the regulated 3.3v supply). Finally, feed the unregulated supply to the upstream side of each of the three LC filters, and use a separate 3.3v regulator on the downstream side for each supply. In each case, note carefully (at a lot of different output frequencies) the general output noise level and the presence of any spurs and birdies in the output, as well as any logic faults you find (wrong frequency, system hangs up, bus errors, etc.). It might be more instructive to run those steps backwards -- first, see how it works with the most complex (and presumably best) supply, then try the simpler circuits and see what problems crop up. Of course, with either test protocol it is difficult to know whether you have tried every operating state that could cause a problem, so play with it quite a while with each setup and try to use every function and combination. As Chris said, you need to be very careful with your grounds. These chips are intended to be put on boards with four or more layers. The AD evaluation board has four layers with a common ground plane for the analog and digital circuitry -- it is possible you could do better with more careful attention to grounding. Best regards, Charles ___ 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. -- 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. ___ 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] Unusual 10544A
On 13/03/14 22:11, Tom Van Baak (lab) wrote: Do you have a photo? I have a large collection of hp oscillators here and do not see a 10544 with SMB. Are you sure it's not 10811? Then again, there are 10544A s/n 1528Ax mounted on a 15-pin PCB (05238-20027) which has a SMB connector. That board is a quick and dirty carrier for 10544 or 10811 if you like to just test-run them. Cheers, Magnus /tvb (i5s) On Mar 13, 2014, at 12:44 PM, Mark Kahrs mark.ka...@gmail.com wrote: Jerry Johnson has the following question: Some of the documents that I have found show pins and feed throughs with SMB right angle connectors for RF and probably control voltage. This one doesn't have the SMB connecgtor, just pins. The case says 10544A part number (which I've not yet searched on) 1528A06401 but finding a used on probably won't find the internal information that I would like to have. Anyone seen this before? ___ 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] Power Supply for AD9852 / AD9854
I do not know if this is of interest or would be applicable. Wenzel uses their Finesse Voltage Regulator in many products which I may be better described as active noise cancelling regulator. From: albertson.ch...@gmail.com Date: Sat, 15 Mar 2014 22:36:23 -0700 To: t...@patoka.org; time-nuts@febo.com Subject: Re: [time-nuts] Power Supply for AD9852 / AD9854 On Sat, Mar 15, 2014 at 9:21 PM, d0ct0r t...@patoka.org wrote: Many thanks indeed for detailed answer ! Yes, I will using Evaluation Board for my project. Then it is already done for you. They have added all the bypass caps already on the board. Not much left for you to do. In fact you can't do anything because all the important design work happens within millimeters of the power and ground pins. -- Chris Albertson Redondo Beach, California ___ 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] Power Supply for AD9852 / AD9854
On 3/16/14 8:13 AM, d0ct0r wrote: Thanks ! Looks like I am on the right track. I've attached couple of documents which could be useful. I'am going to use two separated voltage regulators for VCC/AVDD and DVDD. And use 10 Ohm / 100Mhz ferrite board and few capacitors to separate VCC and AVDD. those parts dissipate a fair amount of heat, and they're not very big. If you turn on everything in the 9854 AND run it at 300 MHz clock, it draws about 1.2 Amps (@ 3.3V) which is about 4 Watts.. that's a lot of power to get out of the part and keep Tj reasonable. Board layout to get the heat out is very important. If they get too hot, they start to act flaky. You get extra spurs and more importantly, they don't respond to the programming properly (e.g. you send the serial stream to program frequency X, and instead it programs some different frequency). The heat sink of the AD9854ASVZ 80-lead TQFP package must be soldered to the PCB. Adequate dissipation of heat from the AD9854 relies on all power and ground pins of the device being soldered directly to a copper plane on a PCB. In addition, the thermally enhanced package of the AD9854ASVZ has an exposed paddle on the bottom of the package that must be soldered to a large copper plane, which, for convenience, can be the ground plane. ___ 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] Power Supply for AD9852 / AD9854
Sorry, I forgot to add the link: http://www.wenzel.com/documents/finesse.html Thomas Knox From: act...@hotmail.com To: time-nuts@febo.com Date: Sun, 16 Mar 2014 09:46:04 -0600 Subject: Re: [time-nuts] Power Supply for AD9852 / AD9854 I do not know if this is of interest or would be applicable. Wenzel uses their Finesse Voltage Regulator in many products which I may be better described as active noise cancelling regulator. From: albertson.ch...@gmail.com Date: Sat, 15 Mar 2014 22:36:23 -0700 To: t...@patoka.org; time-nuts@febo.com Subject: Re: [time-nuts] Power Supply for AD9852 / AD9854 On Sat, Mar 15, 2014 at 9:21 PM, d0ct0r t...@patoka.org wrote: Many thanks indeed for detailed answer ! Yes, I will using Evaluation Board for my project. Then it is already done for you. They have added all the bypass caps already on the board. Not much left for you to do. In fact you can't do anything because all the important design work happens within millimeters of the power and ground pins. -- Chris Albertson Redondo Beach, California ___ 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] Power Supply for AD9852 / AD9854
I would assume that using two voltage regulators will spread the load. For the AD9851 I'am planning to put external radiator glued on top of it. Regards, V.P. those parts dissipate a fair amount of heat, and they're not very big. If you turn on everything in the 9854 AND run it at 300 MHz clock, it draws about 1.2 Amps (@ 3.3V) which is about 4 Watts.. that's a lot of power to get out of the part and keep Tj reasonable. Board layout to get the heat out is very important. If they get too hot, they start to act flaky. You get extra spurs and more importantly, they don't respond to the programming properly (e.g. you send the serial stream to program frequency X, and instead it programs some different frequency). The heat sink of the AD9854ASVZ 80-lead TQFP package must be soldered to the PCB. Adequate dissipation of heat from the AD9854 relies on all power and ground pins of the device being soldered directly to a copper plane on a PCB. In addition, the thermally enhanced package of the AD9854ASVZ has an exposed paddle on the bottom of the package that must be soldered to a large copper plane, which, for convenience, can be the ground plane. -- 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] Power Supply for AD9852 / AD9854
I would assume that using two voltage regulators will spread the load. For the AD9851 I'am planning to put external radiator glued on top of it. One of my commercial projects used eight x AD9852. During development they definitely needed small heat sinks glued on top of each chip. I discovered that it's quite easy to cook a chip. In the final version it was possible to switch off many of the internal blocks so that the heat sinks were no longer necessary. .. Zim ___ 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] Power Supply for AD9852 / AD9854
My versions of a DDS using two AD9910 in Quadrature http://members.wideband.net.au/gzimmer/QuadDDS/default.html regards ... Zm ___ 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] Power Supply for AD9852 / AD9854
On 3/16/14 9:34 AM, d0ct0r wrote: I would assume that using two voltage regulators will spread the load. For the AD9851 I'am planning to put external radiator glued on top of it. It's not the power dissipation of the regulators that's the concern, it's the dissipation of the 9854. A heatsink on top doesn't do much for it, since the thermal path is out through the bottom and/or the leads. Of course, if your regulators are sharing the thermal path, then dissipation in the regulators becomes a concern too. Read the data sheet and the ap note for details. The eval board works OK most of the time. I've encountered flaky behavior but that could have been from other causes. The 9854 is the part that was used in the Flex-Radio SDR1000, but most of the options were powered off, so the dissipation was in the 1 watt range. That particular board would overheat in an enclosure if you didn't have a fan blowing on it. ___ 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] Power Supply for AD9852 / AD9854
Hi If you use multiple regulators for the same supply and they don’t come up at the same time, odd things can happen. On some chips those odd things include smoke. In most cases where it fails, the more common effect is the internal reset does not work properly and you can’t talk to the chip. You really need a multi layer board to heat spread these chips, you also need to reflow solder them to get the bottom pad properly connected to the via’s under the chip. Unless it’s already on a board, this is not a simple chip to use in a home environment. Bob On Mar 16, 2014, at 12:34 PM, d0ct0r t...@patoka.org wrote: I would assume that using two voltage regulators will spread the load. For the AD9851 I'am planning to put external radiator glued on top of it. Regards, V.P. those parts dissipate a fair amount of heat, and they're not very big. If you turn on everything in the 9854 AND run it at 300 MHz clock, it draws about 1.2 Amps (@ 3.3V) which is about 4 Watts.. that's a lot of power to get out of the part and keep Tj reasonable. Board layout to get the heat out is very important. If they get too hot, they start to act flaky. You get extra spurs and more importantly, they don't respond to the programming properly (e.g. you send the serial stream to program frequency X, and instead it programs some different frequency). The heat sink of the AD9854ASVZ 80-lead TQFP package must be soldered to the PCB. Adequate dissipation of heat from the AD9854 relies on all power and ground pins of the device being soldered directly to a copper plane on a PCB. In addition, the thermally enhanced package of the AD9854ASVZ has an exposed paddle on the bottom of the package that must be soldered to a large copper plane, which, for convenience, can be the ground plane. -- 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. ___ 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] Power Supply for AD9852 / AD9854
Unless it’s already on a board, this is not a simple chip to use in a home environment. Nevertheless, some of us do manage. But it's true, the AD9852/AD9854 does run very hot. It's worth mentioning that the AD9910/AD9912 family runs much cooler. Mine aren't even warm to the touch. This of course is due to the power hungry parts of the chip running on 1.8V instead of 3.3V . Zim ___ 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] Power Supply for AD9852 / AD9854
You have not said any thing as to what you expect to get out of the DDS and how important certain parameters are. We recently did a AD 9913 that Tom tested extensively http://www.leapsecond.com/pages/ad9913/ using a single supply for the DDS. Some may take exception but it works for us. The AD 9913 is nice for time nuts applications since it allows precise offsets and we use it in applications like Dual Mixer and what I call the Austron circuit, a circuit that is a single channel digital mixer with ping pong counter and yields 1 E-12 in 1 second. Not ready for release yet. AD 9913 board is attached. Bert Kehren In a message dated 3/16/2014 12:36:48 P.M. Eastern Daylight Time, t...@patoka.org writes: I would assume that using two voltage regulators will spread the load. For the AD9851 I'am planning to put external radiator glued on top of it. Regards, V.P. those parts dissipate a fair amount of heat, and they're not very big. If you turn on everything in the 9854 AND run it at 300 MHz clock, it draws about 1.2 Amps (@ 3.3V) which is about 4 Watts.. that's a lot of power to get out of the part and keep Tj reasonable. Board layout to get the heat out is very important. If they get too hot, they start to act flaky. You get extra spurs and more importantly, they don't respond to the programming properly (e.g. you send the serial stream to program frequency X, and instead it programs some different frequency). The heat sink of the AD9854ASVZ 80-lead TQFP package must be soldered to the PCB. Adequate dissipation of heat from the AD9854 relies on all power and ground pins of the device being soldered directly to a copper plane on a PCB. In addition, the thermally enhanced package of the AD9854ASVZ has an exposed paddle on the bottom of the package that must be soldered to a large copper plane, which, for convenience, can be the ground plane. -- 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. AD 9913.pcb Description: Binary data ___ 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] Power Supply for AD9852 / AD9854 correction
Correction I did put pin 4 on the same regulator as the PIC. Had to have one for the PIC so why not use it. Do not know if it made a difference. Bert In a message dated 3/16/2014 3:58:20 P.M. Eastern Daylight Time, ewkeh...@aol.com writes: You have not said any thing as to what you expect to get out of the DDS and how important certain parameters are. We recently did a AD 9913 that Tom tested extensively http://www.leapsecond.com/pages/ad9913/ using a single supply for the DDS. Some may take exception but it works for us. The AD 9913 is nice for time nuts applications since it allows precise offsets and we use it in applications like Dual Mixer and what I call the Austron circuit, a circuit that is a single channel digital mixer with ping pong counter and yields 1 E-12 in 1 second. Not ready for release yet. AD 9913 board is attached. Bert Kehren In a message dated 3/16/2014 12:36:48 P.M. Eastern Daylight Time, t...@patoka.org writes: I would assume that using two voltage regulators will spread the load. For the AD9851 I'am planning to put external radiator glued on top of it. Regards, V.P. those parts dissipate a fair amount of heat, and they're not very big. If you turn on everything in the 9854 AND run it at 300 MHz clock, it draws about 1.2 Amps (@ 3.3V) which is about 4 Watts.. that's a lot of power to get out of the part and keep Tj reasonable. Board layout to get the heat out is very important. If they get too hot, they start to act flaky. You get extra spurs and more importantly, they don't respond to the programming properly (e.g. you send the serial stream to program frequency X, and instead it programs some different frequency). The heat sink of the AD9854ASVZ 80-lead TQFP package must be soldered to the PCB. Adequate dissipation of heat from the AD9854 relies on all power and ground pins of the device being soldered directly to a copper plane on a PCB. In addition, the thermally enhanced package of the AD9854ASVZ has an exposed paddle on the bottom of the package that must be soldered to a large copper plane, which, for convenience, can be the ground plane. -- 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. ___ 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] Frequency Counter using OCXO and MCU
Tom Harris celephi...@gmail.com On 13 March 2014 01:21, Chris Albertson albertson.ch...@gmail.com wrote: Sorry forgot to add this. As for delayed turn on. That can work but why not simply have the software go into a 5 or 10 second wait before it does anything else. Display warming up or please wait on the LCD. Never present the customer with this sort of message. Something like optimising settings or contacting boot sever... OK. Makes them think that they have got value for money. ___ 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.
