Patent ID: 8278960
Filing Date: 2012-10-02
Classification: G01R

Abstract:
1. A measurement circuit for measuring a quiescent current of a circuit under test, the measurement circuit comprising: a comparator having a first input terminal for receiving a reference voltage, a second input terminal coupled to the circuit under test, and an output terminal; a current source having a first terminal coupled to a first power supply voltage terminal, and a second terminal for providing a current to the circuit under test; a first switch having a first terminal coupled to the second terminal of the current source, a second terminal coupled to the circuit under test, and a control terminal coupled to the output terminal of the comparator; a first counter having a first input terminal coupled to the output terminal of the comparator, a second input terminal for receiving a clock signal, and an output terminal for providing a first counter value associated with the quiescent current; and a second counter having a first input coupled to the first power supply voltage terminal, a second input for receiving the clock signal, and an output for providing a second counter value, wherein an amount of quiescent current is proportional to a ratio of the first counter value to the second counter value.