| 摘要 |
A circuit to generate a reference voltage from a power supply based on a predetermined voltage level, the reference voltage for use by a switched capacitor analog to digital converter includes a follower connected between the power supply and a current source to output the reference voltage. An amplifier is connected in a negative feedback arrangement with the reference voltage and the predetermined voltage level so as to provide an output, and a current sink is connected to the output of the amplifier. A charge pump provides the current sink with a voltage higher than the power supply, and the follower is driven based on the current sink. The charge pump includes a pair of series-connected switching legs, each switching leg being connected to a biasable capacitor, and being driven in diagonally complementary operation together with biasing of the capacitor, so as to provide the voltage for the current sink.
|
