Hello,
An oscilloscope shot shows that an overshoot voltage at CSD95490Q5MC's SW pin is about 20 V and is within its absolute Max rating (VIN to VSW (10 ns)) of 23 V. However, a more margin is required for the design and I wonder if the absolute Max rating can be relaxed for a narrower overshoot voltage. Can it be relaxed to 25 V for an overshoot of 3 nanoseconds, for example?
Enlarged
I'd like to ask one more question.
The addition of a bootstrap resistor RBOOT is considered to reduce this overshoot voltage. However, the design rule requires the power rating of the RBOOT to be 0.03125 W or less. Can it be achieved under the following operating conditions?
- VIN = 12 V
- VOUT = 0.78 V
- fSW = 600 kHz
- IOUT = 21 A per phase (two-phase operation)
- CBOOT = 0.1 µF
Quick feedback is highly appreciated.
Best regards,
Shinichi Yokota