Hello,
Some time ago I built a simple I/V stage for my DIY TDA1541 DAC.
That stage used a 47 ohm resistor for I/V, followed by a Sowter 8347 step-up transformer.
It performed well, but output voltage was much lower than usual and high output impedance made interfacing critical.
Now I am planning to lower the I/V resistor (in order to reduce distortion) and add an op-amp (OPA627) gain stage at the output which, hopefully, will also lower output impedance.
I am not an EE, so I would appreciate opinions from you skilled friends.
Best regards.
Paul
please look at the attached schematic
Some time ago I built a simple I/V stage for my DIY TDA1541 DAC.
That stage used a 47 ohm resistor for I/V, followed by a Sowter 8347 step-up transformer.
It performed well, but output voltage was much lower than usual and high output impedance made interfacing critical.
Now I am planning to lower the I/V resistor (in order to reduce distortion) and add an op-amp (OPA627) gain stage at the output which, hopefully, will also lower output impedance.
I am not an EE, so I would appreciate opinions from you skilled friends.
Best regards.
Paul
please look at the attached schematic
Attachments
The datasheet do recommend the output voltage to be no less than 25mV. People suggest that the output current is around 1mA so less than 25ohm i/v resistor would do. (one of my friend prefer 39R instead) But then you need around 1:100 gain to get 2V out.
OPA637 is another option when gain>5 is required.
Correct me if I'm wrong but this circuit yields 180deg out of phase. I'm nobody in electronic world either.
OPA637 is another option when gain>5 is required.
Correct me if I'm wrong but this circuit yields 180deg out of phase. I'm nobody in electronic world either.
- Status
- Not open for further replies.