ZERO-CURRENT START-UP CIRCUIT

摘要

A zero-current start-up circuit for a reference circuit which is initially unbiased and which has internal nodes that needs to be regulated to a predetermined voltage. When the start-up circuit is enabled, a switching transistor is turned on which enables the reference circuit to generate an internal reference current which regulates an output current to a predetermined value set by the reference circuit. The output current flows through a voltage drop device and when the voltage level reaches a predetermined value, the start-up circuit is disabled eliminating the current path.