INA 103 and digital potentiometer

[usul27]

Has anyone paired an INA 103/263 or similar with a digital potentiometer to adjust the gain? Thinking about this combination for a RIAA stage to adjust the gain.

Found this from AD: Circuit Note | CN0114 | Low Cost, High Voltage, Programmable Gain Instrumentation Amplifier Using the AD5292 Digital Potentiometer and the AD8221 In-Amp | Analog Devices

Any experiences or opinions?

 

[kevinkr]

I've used them in the front ends of ATE instrumentation for calibration, but have not listened to them.

 

[Bonsai]

If you are looking for balanced input with adjustable gain, another (easier) approach is to simply use a PGA2320. It has two channels, use one for hot, one for cold and it has built in 255 step gain control (SPI). I am doing this on my latest pre-amp design. Works very well indeed. Have a look at my website for some pictures.

 

[usul27]

I had a look at the specs. I forgot to say that I want to use the INA 103 as input stage for MM and MC.
Seems, that the PGA2320 is not suitable for this application (performance best on 3V signal input, input impedance <600 Ohm). This would need at least additional preamplification and buffering.

 

[Bonsai]

You are correct - the PGA2320 is designed for line level applications. If you are looking for MM or MC input levels, then indeed you need something else.