| 摘要 |
A bandgap reference voltage source comprises a band-gap core circuit, a pre-regulator circuit, a switch circuit and a start-up circuit. The start-up circuit, after being powered on, provides an initial bias current for the operational amplifier in the bandgap core circuit. The pre-regulator circuit provides a pre-regulated voltage for the bandgap reference core. A comparator judges the output state of the bandgap core circuit and selects, using a switch circuit, either the bandgap core circuit output VBG or the power supply partial voltage as the reference voltage of the pre-regulator circuit. Use of the pre regulator may increase the power supply rejection ratio of the bandgap reference voltage source. |
