| 摘要 |
PURPOSE:To transmit a signal in the form of a current by designing the circuit so as to receive an output signal of an LSI with a transistor (TR) of the open emitter form thereby decreasing the input impedance of an input circuit. CONSTITUTION:An output circuit of the LSI1 is provided with the 1st and 2nd TRs Q1, Q2 constituting a current switch. The said circuit is connected to a current source 3. The collector of the TRQ2 is connected to the base of the 3rd TR of the open emitter output. A prescribed reference voltage Vref is applied to a base of the TRQ2 and a signal IN formed by the LSI1 is fed to the base of the TRQ1. The emitter of the 3rd TRQ3 is connected to the emitter of the 4th TRQ4 in the LSI2 in the form of open emitter. Thus, the input impedance of the LSI2 becomes very small. |
