Hello everyone,
I was studying a tl494 based half bridge smps
I came across the current sense section opamp pin 15 & pin16
Now pin16 is connected directly to the ground
But there is some arrangment made to pin 15
I have drawn a part of it
Please can anyone help me what is a purpose of “103 trimpot” and why does the transistor “ 2n2222a” is also used which Is connected to microcontroller pic18f452
Looks like a programmable output current limit. Without the full schematic, we can only guess how it's connected to the µC and what's the exact function. In case of doubt, you need to look into the µC code.
Sir this is a half bridge smps
Now
When the output is 0v the transistor base voltage given from microcontroller is also 0v
Once increased till 100v (smps max ) the highest voltage given from mcu to the transistor base is 0.24v