Light source device and light source drive circuit thereof

• Main Author: ZHANG CONGHAO
• Format: Patent
• Language: Chinese; English
• Published: 14.07.2010
• Subjects: ADVERTISING; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; CRYPTOGRAPHY; DISPLAY; EDUCATION; ELECTRIC HEATING; ELECTRIC LIGHTING NOT OTHERWISE PROVIDED FOR; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; PHYSICS; SEALS

The invention relates to a light source device and a light source drive circuit thereof. The light source drive circuit comprises an operational amplifier, a transistor and a switching unit. The first input end of the operational amplifier is coupled to a preset voltage. The first end of the transistor is coupled to a light source, and the control end thereof is coupled to the output end of the operational amplifier. The first signal end of the switching unit receives a first voltage larger than the preset voltage, the second signal end thereof is coupled to the second input end of the operational amplifier, the third signal end thereof is coupled to the second end of the transistor, and the enabling end thereof receives a drive voltage. When the drive voltage is enabled, the voltage of the third signal end is transferred to the second signal end. When the drive voltage is disabled, the voltage of the first signal end is transferred to the second signal end.