Patent ID: 7772923
Filing Date: 2010-08-10
Classification: G01R

Abstract:
1. A test circuit, for checking a programmable gain amplifier (PGA), comprising: a signal generator, coupled to the PGA, for outputting a test input signal to the PGA, wherein the PGA generates a test output signal according to the test input signal; a gain controller, coupled to the PGA, for outputting a gain control signal to the PGA to adjust a gain of the PGA, wherein the test output signal is varied with the gain of the PGA; a test level output circuit, coupled to the PGA, for referring the test output signal to output a first test level when the gain of the PGA is a first gain, and for referring the test output signal to output a second test level when the gain of the PGA is a second gain, wherein the first gain is different from the second gain; a comparison circuit, coupled to the test level output circuit, for comparing the first test level and the second test level to generate a result signal; and an identifying circuit, coupled to the comparison circuit, for identifying whether the result signal complies with an expected result, wherein the expected result is based on the gain control signal.