Chris said:
It often helps to "decouple" outputs from their loads using small resistors,
especially if the loads have a capacitive component.
Often opamps begin oscillating caused by this component.
The small resistors used will cause a small voltage drop which will be
compensated by the opamp itself, so operation remains identical.
for IC1(A) (less needed here, but might help)
- small resistor (say 100e) from pin 1 to feedback junction
- small resistor (say 100e) from feedback junction to pin 2
(cut direct connection of course)
- small cap directly from pin1 to pin2
for IC1(D) (needed if load (out1) has a capacitive characteristic)
- small resistor (say 100e) from pin 14 to feedback junction
- small cap directly from pin14 to pin 13
for IC1(B) (needed if load (out2) has a capacitive characteristic)
- small resistor (say 100e) from pin 7 to feedback junction
- small resistor (say 100e) from feedback junction to pin 6
(cut direct connection of course)
- small cap directly from pin7 to pin6
for IC1(C) (needed if load (out3) has a capacitive characteristic)
- small resistor (say 100e) from pin 8 to feedback junction
- small resistor from feedback junction to pin 9 (cut direct connection of
course)
- small cap directly from pin 8 to pin 9
principle:
(see drawing in notepad using fixed font)
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