Semiconductor laser drive circuit including a waveform generator voltage-to-current conversion circuit

Abstract

A semiconductor laser drive circuit of the present invention reduces the number of wires, solves the out-of-timing problem of pulses due to differences in wire length, and emit short light pulses at a high transfer rate. A common emitter circuit () converts a voltage signal (J) input at an input port () into a current signal and, when reading information, adds the current signal to a signal output from a high-frequency oscillator circuit (). High frequency components of the current signal converted from the voltage signal (J) within a bandwidth of a transistor (Q) are boosted. Degradation of the output signal of the high-frequency oscillator circuit () is kept at a minimum by a common base circuit including the transistor (Q). A current switch circuit () cuts off or lets through the output current of a current mirror circuit ().