| 摘要 |
PURPOSE:To transmit a high speed signal with low power by controlling a transistor (TR) while monitoring the characteristic of the TR so that an ON resistance of an output circuit is matched with an impedance of a transmission line. CONSTITUTION:Circuits 24, 25 are circuits to control the gate width of an output NMOS TR, input a voltage across resistors 22, 23 to observe the drain current of monitor NMOS TRs 20, 21 and output signals 26, 27 designating a TR to be operated among trimming NMOS TRs 2-5, 7-10 by using the voltage. The control signals 26, 27 are fed to all output circuits in a LSI chip, the gate width of the output TR is adjusted automatically so that the ON-resistance is in matching with the impedance of the transmission line. |
