Patent ID: 6437575
Filing Date: 2002-08-20
Classification: G01R

Abstract:
A low-voltage detecting circuit for detecting the voltage level of power sources, comprising:a switching module; a charge/discharge module, connected to said switching module; a discharge detecting module, connected to said charge/discharge module; and a control module including a timer, wherein said control module is connected to said switching module and said discharge detecting module; wherein said control module outputs a first control signal to the switching module to drive said charge/discharge module to execute charging operation; after a pre-determined period, said control module resets said timer to zero and activate said timer, meanwhile, said control module outputs a second control signal to said switching module to drive said charge/discharge module to execute discharging operation; when said charge/discharge module discharges to a first pre-determined voltage, said discharge detecting module outputs a first signal to said control module to stop the timing calculating of said timer and outputs a calculated value; and then according to the calculated value to determine the voltage level of power sources.