ZHCSM42C may 2020 – april 2023 TPS543320
PRODUCTION DATA
A 0.1-µF ceramic capacitor must be connected between the BOOT and SW pins for proper operation. The capacitor must be rated for at least 10 V to minimize DC bias derating.
A resistor can be added in series with the BOOT capacitor to slow down the turn-on of the high-side MOSFET and rising edge overshoot on the SW pin, which comes with the trade off of more power loss and lower efficiency. As a best practice, include a 0-Ω placeholder in all prototype designs in case parasitic inductance in the PCB layout results in more voltage overshoot at the SW pin than is normal, which helps keep the voltage within the ratings of the device and reduces the high frequency noise on the SW node. The recommended BOOT resistor value to decrease the SW pin overshoot is 2.2 Ω.