Hello,
About a characteristic of LM358B,
I want to know the test circuit to measure a following parameter in a data sheet
1. Open-loop voltage gain
test condition : VS = 15 V; VO = 1 V to 11 V; RL ≥ 10 kΩ, connected to (V-)
2. Gain bandwidth product
test condition : not listed
Thank you
Hello Hiroki,
1) For any circuit (in production test, a servo) where VS = 15 V, RL ≥ 10 kΩ, connected to (V-), record input voltage error with Vo at 1V and 11V, call this A , B
Gain = (11V-1V) / (A-B) = 10V/(A-B) = dVOUT = dVIN
2) For example, 10kHz * 42dB = 10kHz * 126 =1.26MHz.
Hi Hiroki,
I guess the test circuit is similar to this servo loop scheme:
And the AOL according to this simulation would be about
AOL = dV4 / dVF2 x (1 + 100k / 100) = 10V / 167mV x 1001 = 59.9V/mV.
Kai
