Patent ID: 7919982
Filing Date: 2011-04-05
Classification: H03K

Abstract:
1. A digital interface sensing apparatus comprising: a sensor to sense an external analog signal; an analog detecting circuit to detect the sensed analog signal from the sensor; an analog to digital (A/D) converter to convert the sensed analog signal to a digital signal, and receive a clock signal and a data demand signal, wherein the A/D converter sends the digital signal data in response to the A/D converter receiving the clock signal and the data demand signal; a signal cable; and an interface switch circuit comprising a multiplexer and a recommended standard 422 (RS-422) transceiver, the RS-422 transceiver connected between the A/D converter and the multiplexer to switch RS-422 digital signal and transistor-transistor logic (TTL) signal, the multiplexer connected between the A/D converter and the signal cable to selectively transfer RS-233 and RS-422 signals between the A/D converter and the signal cable.