SNVSA46B June 2014 – January 2018 LM46001
The driver of the HS switch requires a bias voltage higher than VIN when the HS switch is ON. The capacitor connected between CBOOT and SW pins works as a charge pump to boost voltage on the CBOOT pin to (VSW + VCC). The boot diode is integrated on the LM46001 die to minimize the bill of materials (BOM). A synchronous switch is also integrated in parallel with the boot diode to reduce voltage drop on CBOOT. A high-quality ceramic 0.47 µF 6.3 V or higher capacitor is recommended for CBOOT.