Showing results for 
Search instead for 
Did you mean: 

I have a problem with the L6498D driver, the high-side does not work

Associate II

design a driver for full h-bridge using two L6498D, when i activate the LIN input the LVG output is activated and manages to turn on the low side MOSFET, but when i activate the HIN input i get a strange output of 9.6v on HVG and i am using 12v at VCC of the L6498D. This strange voltage level always appears, when I always keep the HIN input high or when there is a PWM in HIN, in both situations the HVG output is always the same, 9.6v. What could be happening?






did you solve the problem in the meantime?

In order to work properly, the bootstrap structure requires LIN to be active and consequently OUT/S1 pin connected to GND for the time needed to pre-charge the bootstrap capacitor.

With an external bootstrap diode, alternatively, the circuit topology/load should allow the OUT/S1 pin to go at GND level (or less) from time to time in order to achieve the same result.

Every time HIN is activated, there should be a residual charge/voltage in the bootstrap capacitor which is higher than the UVLO turn-on threshold (max).

I hope this (so late answer) helps,