Please help me analyze the role of R11 and how to select its value (because I usually connect a 2k resistor here, but I don’t know why)
Michelle ポストする January 18, 2021
And this resistance, the main reason should be that the 431 current is not enough.
Micah ポストする January 18, 2021
The diode of the optocoupler will also flow current. Is this current not enough?
Michelle ポストする January 18, 2021
The problem is that sometimes when you want to turn on the maximum PWM, you don't want the optocoupler to have current (or only a relatively small current).
Colin ポストする January 18, 2021
Mainly to provide enough working current for 431.