Hi team，
My customer designed LM5088-2 refer to the schematic below, when the inductive current is 12A and the protection value of 14A is not reached, the hiccup mode occurs as shown in the following figure.
However, this behavior will return to normal after replacing the chip. Could you please help give some suggestions?
CH1: Inductive Current; CH2: HG pin to SW pin voltage ; CH3: RT/SYNC pin 5 to GND voltage; CH4:RAMP pin to GND
Regards,
Ivy
Hello Ivy
I looks like the issue is related with the switching behavior when the duty cycle reaches the device's maximum duty cycle limit.
Would you please check if the issue happens when the duty cycle is <70% ?
Also, please try these quick fix ideas.
1. connect C20 to the negative connection of R5.
2. Populate 100pF filter capacitor very close to the CS and CSG pins.
3 Populate 500Ohm filter resistors in addition with 100pF filter capacitor
-EL
