); SAEximRunCond expanded to false Errors-To: [EMAIL PROTECTED] RETRY Vos is 1 uV/C guaranteed, 0.15 V/C typical. (And you can get a high-spec part with the latter guaranteed.) Can take 24 V supply, and pull to within 1.5V of the rails over the full temperature range, so can produce +/-10V.
Also pretty cheap. Even at 0.1 ppm/V, that would be a worst-case 1e-13/C tempco, which is comparable to the best double-oven oscillators, and it'll usually be much less than that. Of course, the tempco of the resistors in the circuit is also an issue. I haven't done a full sensitivity analysis, but do know that thin-film resistors usually track very well, so as long as you can keep them isothermal, it'll work well. One trick I use to get better tracking is to build ratios out of multiples of a single resistor value. As I said in my other mail: - I really fail to see how the LT1085 power supply circuits work at all. An LT1085 is an adjustable three-terminal regulator with a reference voltage (where it tries to keep Vout - Adj) of 1.25V. U4 will keep the Vcc net 1.25V above Gnd, and U5 will do just plain strange things. Having Vin lower than Vout will turn on internal diodes and short them together. - Wouldn't it make more sense to configure U1A and U1B as simple non-inverting amplifiers, that will present a high-impedance load to EFC_input, thereby avoiding the need for all the J8-J10 and J21-J23 jumpers? You need a 3.3V reference for the U1A circuit rather than 1.5V, but that's easy enough to make out of a TL431. _______________________________________________ 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.