I've been using the Analog Devices Spice model in LTSpice to model the AD73
4 running with a current output - see Figure 25 on page 13 of the Rev E AD 734 data sheetWhen running a roughly 15kHz sine wave through the device, the positive cur rent output limits at something between +200uA and +280uA.
The voltage at the W and Z1 outputs of the AD734 is well below the rail.
I've tried 2.2k, 6.8k and 15k current setting resistors. Only with 15k did the voltage at the W and Z1 outputs get high enough to be interesting.
The current clipped at +200uA with 2.2k, +282.77uA at 6.8k and +267.94uA at 15k.
The negative-going excursions looked perfectly sinusoidal, and went down to -350uA.
Working in another region of operation, with more head-room, the currents c lamped a lot higher, at about +800uA, when the negative currents were getti ng down to -2.4mA.
It looks very much as if there's some kind of silly mistake in the AD734 Sp ice model (which would interest Jim Thompson, who wants to sell Analog Devi ces better Spice models).
If the actual device acted like the model, the data sheet wouldn't talk abo ut +/-10mA output current limits (as it does on page 13).
It's easy enough to hand-edit .cir files, if you kno0w what you are doing. Any advice will be gratefully received. I probably should have raised this with Analog Devices directly, but the price they charge for the AD734 means that they can't be selling many of them, which doesn't suggest that I'd ge t a prompt response.