Low-voltage, low-power bandgap reference circuit with bootstrap current

摘要

A bandgap reference generator includes a bandgap reference circuit, a sensing circuit, and a current injector circuit. The bandgap reference circuit includes an input for receiving a supply voltage V_CC and an output for providing a reference voltage V_REF. The bandgap reference circuit also has a first internal node with a first voltage and a second internal node with a second voltage. The sensing circuit is operatively coupled to the bandgap reference circuit for sensing the second voltage at the second node. The current injection circuit is responsive to the sensing circuit for injecting bootstrap current into the first internal node until the second voltage reaches a threshold voltage. The current injection circuit is operative to inject the bootstrap current into the first internal node during an initial condition of the bandgap reference circuit to cause the bandgap reference circuit to quickly transition to a desired operating state. The injection of bootstrap current is discontinued when the second voltage reaches the threshold voltage reflecting that the desired operating state is achieved.