Bootstrap scheme for BULK-BOOST converter

摘要

A bootstrap circuit for a voltage converter includes a bootstrap capacitor, a stable current module for generating a stable output current according to a stable output voltage, a current mirror module having a first branch circuit for generating a current signal according to the stable output current, and a charge module including a cascode transistor module including a plurality of transistors serially connected and a charge resistor for generating a conduction voltage according to the current signal, and an output circuit coupled to the current mirror module and the cascode transistor module for outputting the conduction voltage to charge the bootstrap capacitor.

主权项

1. A bootstrap circuit for a voltage converter comprising:
a bootstrap capacitor; a stable current module for generating a stable output current according to a stable output voltage; a current mirror module comprising a first branch circuit for generating a current signal according to the stable output current; and a charge module comprising:
a cascode transistor module comprising a plurality of transistors serially connected and a charge resistor for generating a conduction voltage according to the current signal; andan output circuit coupled to the current mirror module and the cascode transistor module for outputting the conduction voltage to charge the bootstrap capacitor.