IC CHIP CAPABLE FOR ADJUSTING LEVEL OF INPUT/OUTPUT SIGNAL

摘要

PURPOSE: An IC chip capable for adjusting the level of input/output signals is provided to make it easier to have a measure to stop noises and electromagnetic interference and to match signals between circuit using difference power sources. CONSTITUTION: In an IC chip capable for adjusting the level of input/output signals, an IC chip(100) communicates with a micro process(200) through a serial port. A memory(110) works as a register storing control values provided by the microprocessor(200). A digital/analog converter(120) converts the control values into analog signals. A comparator(130) receives the analog signal through a non-inverted terminal and an operational voltage(Vcc) given to the IC chip through an inverted terminal. The comparator(130) produces a result proportional to the difference between the two values. A power amplifier(140) controls the amplification gain responding to the compared result. The amplified output voltage of the power amplifier(140) are given to an output buffer(150) and an input buffer(160) as operational voltages. Thus, the input/output buffers(150,160) have the input/output signals swinging between the operational voltage and the grounding voltage.