I'm facing issue with IR2110S driver while driving 3 winding BLDC motor (24V, 8A rating with Hall sensor feedback) using IFR3710 MOSFET (half bridge configuration).
When varying duty cycle from 0 to 95 present with 5 percent interval, motor running fine. But when varying duty cycle (PWM) from 0 to more than 50 percent suddenly, IR2110S driver IC getting failed sometime. there is no IC heat observed. MOSFET not get damaged. after replacing IC its working fine with 5% duty cycle increment.
With driving the motor, observed some spike on low side MOSFET drain and source terminal. I think low side output section of IR2110 driver circuit failed. This will fail when LO pin voltage with respect to ground less than 0.3V and more than VCC+0.3V. After driver failed, 555 timer IC threshold and discharge pin varying continuously from 0 to 5 voltage linearly and RED gets turned ON then we are stopping low side MOSFET PWM signal.
50 kHz switching frequency 24 V, 8 A bldc motor 24 V input power supply to board (main board) 0.05 ohm external resistor board which has 10 cm distance between main board. Maximum duty cycle should be 90 percent. I want to spinsup directly 0 to 90 percent.
I read relavent answer to "Driver failure when driving IRF3710 mosfet using IR2101 driver" question, which is same like my schematic. Difference is current sensing circuit, 4.7 uF bootstrap capacitor (in my circuit, using 47 uF electrolytic), 50 kHz switching frequency. Gate to source resistor.
Am having doubt on following,
1) Is 47 uF electrolytic and .1 uF ceramic decoupling capaictor enough for my load?
2) Switching frequency is 50 kHz, 47 uF bootstarp capacitor is ok or due to high frequency can I reduce it to 4.7 uF for quike charging and discharge?
3) I plan to use 15 V working voltage, unidirectional TVS diode across gate and source of all MOSFETs to maintain 15V max across all MOSFET G-S terminal. If this is OK then voltage rating is fine for TVS diode?
4) Is external sensing resistor long return path will affect driver performance(10cm length wire connected to external having two 0.1/5W resistor parallel connection)?
5) In driver application note, driver COM pin connected directly to lower side MOSFET source pin. But i connected through sensing resistor which is connected externally (due to lack of space in main board). I plan to remove resistor and connect COM pin directly to Low MOSFET source pin. Is that OK (removing current sensing circuit)?
6) Motor control has three phase sequence, we not found cross conduction condition, so not provided dead time delay. Is this will affect?
7) Is the TVS diode across 24 VDC supply rail is required?
Please provide me the suggestion to resolve this issue.