We have replaced a ne5532 with OPA1662-Q1. The circuit is a simple voltage follower with a capacitive load to decoupling output.
We didn't have problems with the ne5532.
With the opa1662-Q1 we have some broken devices: output pin blocked to -VEE. None particular stress to cause the broken.
Do anyone have already knoledge about this critical aspect of this AO? Any suggest?
Hi Tamara,
The supply rails are +15V -15V nominal.
The input signal come from an OPA1664, same supply rails (+-15V), signal max level 14dBu, 20-20KHz (audio signal). No (or very low) DC.
The output signal expected is the same from input: it isn't expected any amplification. The stage could fit a resistor for a 6dB amplification, not fitted.
Yes, the output is railing to -14V (locked to -14V)
I attach an input signal, output signal of the broken AO (pin1), signal on pin 3 (note the DC component of -4.4V, from -15V). (On pin2 the signal is the same of pin3 but a DC component of -5.1V)
Thank you for your support.
Best Regards
Stefano
Hello Meroni,
I built this circuit in TINA Spice so I can analyze the nodes more carefully. The circuit seems to be behaving as expected. You can see my circuit and the transient analysis.
Can you try swapping out the OPA1662 you have with another one and sharing the results?
-Tamara
Hello Tamara,
thank you for your reply.
Here are the waveforms get with a not broken OPA1662.
They look like the waves obtained by your simulation.
Regards
Stefano Meroni
