PGA2310 - PGA2311 - CS3310: version without OPAMP for outdoor OPAmp connection wanted

The IC type from the headline have two disadvantages for me:
1) The quality standart of the internal OP-Amp is unknown - not very high however
2) the variable resistor for the volume control is located in the NFB. This means, that the THD character is dependend of the level position resp. of the individual adjusted gain factor (particularly by freqencies above 10 KHz).

Therefore for me the question rises up, whether there are other versions, both at whole passive for the analoge signal pad so as with additional pins for use of various external operational amplifiers like AD797, LME49710 etc.

Thanks for advices.
 
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DAC8043 (or similar) in multiplying mode (see datasheet) with quality OA, eg. OPA1642, OPA1612..Results are very good (example in attachment), but uP is a must. It is far better than PGA, MAS, CS or similar..
 

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maxw

Member
2004-06-10 7:23 am
Berlin
interesting advices - thank you very much therefore.
An other question in this case is for me of interest. Which OP-Amp type corresponds to the integrated version at best?
The NE5532, OPA2604 or OPA2132?
Because there is no circuit diagram in the datasheet of PGA2310/2311, this is hard to say for me. Who know this ? The most interesting fact is the topology and the idle current of the output stage.
Maybe anybody can ask by TI this.
Thanks again.
 
An other question in this case is for me of interest. Which OP-Amp type corresponds to the integrated version at best?
Today I would use e.g. OPA1611(or 1612-dual) or Jfet version OPA1641 (1642). There are no information about OA used in PGA, nor output idle current, but quiescent current for whole analogue section is about 10mA (both channels). I used PGA2310, but it was for me not satisfying..Try to find some information about THD(+N) vs.freq at gains other than 0dB, and input levels about 1V RMS, this is most used regime.