PWM with PIC16F88 controlling h-bridge

[deimantas]

Hi,
That schematic looks a bit strange to me.....

First, there doesn't seem to be any low side supply voltage (Vcc) as pin 3 seems to not be connected to anything except the bootstrap capacitor and diode. Only the logic supply (Vdd) seems to actually be connected to any supply rail.

Second, even if pin 3(Vcc) and 9(Vdd) ARE connected they are both connected to +5V while the datasheet for the IR2110 calls for a Vcc of 10-20V. The undervoltage protection for the low the side supply (Vcc) kicks in at around 8V which means the bridge drivers aren't even operating.

/Henrik.

So if i understand correctly i need pin3 connect to 12V supply, y ? Sorry my mistake, its everything okay, just i didn't draw that... pin 3 is connected to 12V supply.

This pin is made HIGH before the main loop then made LOW within the loop but never serviced again if you are wanting to Shut Down again sometime. That's why it's always LOW.

The main point of getting SD low is to make sure that MOSFETS are off at the start. In the loop he used Low sd / high SD for modulating signal and i think i should see that different in tester, or its making turn off/on SD to fast to get that information ? (Sorry for pure language).