Part Number:DRV8353R
Hello.
Several months ago I start to developing bldc motor controller and I select DRV8353RS for driving mosfets. At first it bought a DRV8353RS-EVM for test. I used not heavy motor for it (FL86BLS71). I had a some troubles with auto-tuner but with another attempt I got success. Then after some tests I up supply voltage from 20volt to 40-50 volts and start motor again but it doesn't start and fault led start lighting. Then I start investigate this accident and find that high side mosfet driver of C phase was broken. All of power mosfets stayed healthy. Signals SHC and GHC was short circuit. I had nothing to do and I started do mad experiments. I had suspicions of a suppressor for high side gate and I tried to destroy it by applying voltage between GHC and SHC and to solder one external. Short circuit has gone but looks like suppressor doesn't damaged because at ~15volts something start pass current. Before it I unwire GHC and mosfet gate. After I powered on board and it didn't go to fault. Waveforms at GHC looks good. Then I connected the gate back and it went to fault again. I had no time to wait new parts and I used other half bridge driver for C-phase. Phase A and B and all 3 current shunt still controlled by DRV. It's allowed me to do several tests with motor. After this I made own controller based on DRV8353RS and EVM board. Mosfets, driver and schematic are same. Now I am working at firmware for it. I have some progress of it, torque control work great. But today I damaged DRV again. It happened then I test my code. Motor was spinning and I up supply voltage(from ~20v to ~40v) and it has stopped due to fault. Board start consume more current (now 19mA, was 10mA at 15v and ENABLE = high) and DRV was more hot than early. All mosfets are healthy. I am investigating this accident and now i have next results:
1. It has 250 ohm between GLC and GND, 200 ohm between GLC and VGLD and 420 ohm between VGLD and GND. Looks like low side C driver was damaged.
2. When it powered on. VGLD voltage is around 3 volts.
3. Charge pump has problems too. CPL signal looks like 400khz PWM 3.5 to 0 volts, 50% duty.
4. All other mosfets drivers looks good.
Now I have two damaged DRV8353RS and no idea why it happened and how to fix it. Maybe it due to voltage changing, but I want to use it in similar environment. Have you solution of this problem?
