Patent ID: 8339162

Claim:
A circuit device comprising: a first bi-directional buffer including a first output buffer configured to output a first output signal, and a first input buffer connected to the first output buffer and configured to receive the first output signal; an adjustment controller configured to output a first bi-directional buffer control signal to the first bi-directional buffer for adjusting a voltage level of the first output signal, to monitor an output of the first input buffer, and to adjust the first bi-directional buffer control signal based on the monitoring of the output of the first input buffer; and a second bi-directional buffer including a second output buffer that outputs a second output signal, and a second input buffer connected to the second output buffer, wherein the adjustment controller outputs a second bi-directional buffer control signal to the second bi-directional buffer for adjusting a voltage level of the second output signal based on the monitoring of the first bi-directional buffer, and the first bi-directional buffer is not connected to the second bi-directional buffer.