Other Parts Discussed in Thread: UCC21750-Q1, UCC21750
Hello, I'm studying about Gate Driver IC operation through several measuring test.
In the datasheet of UCC21750-Q1, Output Pull-up resistance value is written as 2.5ohm when output current is -0.1A (9page of UCC21750-Q1 datasheet)
I have few question about this,
1) Output current = -0.1A, negative means sourcing from Gate Driver IC to Power Tr. ? Loading current in GATE PAD.
2) I connected the current load to OUTH(TP12) after connecting VCC=5V, VDD=15V, COM=VE=0V, IN+=5V, IN-=0V and measured OUTH volatage it when loading currentis -0.1A, the OUTH was 14.5V.
Calculating the resistance from VDD to OUTH, Output Pull-up resistance, we can see (15V-14.5V)/0.1A = 5ohms, which is different from 2.5ohms in datasheet.
I thought the on resistance of PMOS in the hybrid pull-up system was measured, and I don't understand that the value was different.
as my calculation based on the information in datasheet, PMOS=2.5ohm/ Total resistance (PMOS parallel NMOS) = 0.6ohm/ NMOS=0.78ohm. Is it right?
Please let me know if there's anything I didn't think of. Thank you.
Best regard,
Yoonjin Kim