Title:
発光素子の駆動回路
Document Type and Number:
Japanese Patent JP4200535
Kind Code:
B2
Abstract:
A drive circuit of a light emitting element capable of setting a desired constant current and capable of operating stably at a high speed while holding a forward direction voltage required for the emission of light even under a low power supply voltage, wherein there is provided an input circuit which receives differential drive signals and outputs differential signals of levels in accordance with the level of a supplied drive voltage; a differential output circuit in which an emitter-connection portion of transistors is grounded via a resistor, the differential signals and are supplied to bases, and a laser diode is connected to a collector of the transistor; a reference voltage generation circuit which generates a reference voltage; a comparison circuit which compares the voltage of the emitter-connection portion with the reference voltage and outputs a signal of the level in accordance with the result of comparison; and a variable voltage supply circuit which generates a voltage in accordance with the input level of the output signal and supplies the same as the drive voltage of the input circuit.
Inventors:
Takayuki Mogi
Takashi Nishimura
Takashi Nishimura
Application Number:
JP4767098A
Publication Date:
December 24, 2008
Filing Date:
February 27, 1998
Export Citation:
Assignee:
ソニー株式会社
International Classes:
H01S5/062; H01L33/00; H01S5/042; H01S5/068
Domestic Patent References:
| JP7007204A | ||||
| JP4271182A | ||||
| JP3175778A | ||||
| JP1181579A | ||||
| JP9107144A | ||||
| JP3036824A | ||||
| JP8017088A | ||||
| JP3048536A | ||||
| JP2194657A |
Attorney, Agent or Firm:
Takahisa Sato