steve_venkat
- May 22, 2017
- 30
- Joined
- May 22, 2017
- Messages
- 30
Its connected to MCU input,The resistor is connected as pull-up resistor...You can't get a negative voltage out, since the '814 output transistor is only connected to a +5V supply.
What AC voltage are you trying to detect? 110V mains?
Its 5mA current required.?If the voltage is constant(230VAC) means 4.k OHM is enough for it..?With 100k resistors I'm surprised you're getting anything at all. This means only 0.5mA through the opto's LEDs. Without referring to the data sheet (coz I can't be bothered to download one) is <1mA sufficient to activate the LEDs?
Its 5mA current required.?If the voltage is constant(230VAC) means 4.k OHM is enough for it..?
But the voltage will vary from 160VAC to 280VAC...
At this point how to choose the resistor value..?