ZHCSH35B November 2017 – May 2021 LM73605-Q1 , LM73606-Q1
PRODUCTION DATA
The driver of the HS switch requires a bias voltage higher than the VIN voltage. The capacitor, CBOOT in the 簡化版原理圖, connected between CBOOT and SW pins works as a charge pump to boost voltage on the CBOOT pin to (VSW + VCC). A boot diode is integrated on the die to minimize external component count. TI recommends a high-quality 0.47-μF, 6.3-V or higher voltage ceramic capacitor for CBOOT. The VBOOT_UVLO threshold is designed to maintain proper HS switch operation. If the CBOOT is not charged above this voltage with respect to SW, the device initiates a charging sequence using the LS switch before turning on the HS switch.