Patent ID: 7288982

Claim:
A signal converting circuit adapted for interconverting RS232 signals with I 2 C signals, the signal converting circuit comprising: a voltage level converter circuit, a first input end of the voltage level circuit connected to an SDA line of an I 2 C interface, an output end of the voltage level circuit connected to a received data pin of an RS232 interface; a power circuit, an input end of the power circuit connected to a request-to-send pin of the RS232 interface and a power supply respectively, and an output end of the power circuit connected to a second input end of the voltage level converter circuit; a signal separation circuit for separating a signal into two separate signals, an input end of the separation circuit connected to a transmitted data pin of the RS232 interface; a signal modifying circuit, a first input end of the signal modifying circuit connected to a first output end of the signal separation circuit, a second input end of the signal modifying circuit connected to the output end of the power circuit, a controlling end of the signal modifying circuit connected to the request-to-send pin of the RS232 interface; and a clamping circuit, a first input end of the clamping circuit connected to a second output end of the signal separation circuit, a second output end of the clamping circuit connected to an output end of the signal modifying circuit, a first output end of the clamping circuit connected to the SDA line of the I 2 C interface, and the second output end of the clamping circuit connected to an SCL line of the I 2 C interface, the clamping circuit adapted for limiting the signal sent from the signal separation circuit and the signal modifying circuit to the specific voltage of the SDA line and SCL line.