Constant-Current Driver Suits LED Apps

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The AL8400 linear LED driver/controller regulates a wide variation of high brightness LED currents via an external transistor. The device can directly operate from 2.2V to 18V and will drive either N-channel MOSFET or NPN transistors. Current sense voltage is 200 mV and an open collector output drives the external pass transistor allowing it to regulate LED currents from tens of milliamps to above an amp. Using an external pass transistor allows power dissipation and maximum drive capability to be optimized.  Longer LED chains needing significantly more than 18V can be driven with minimal additional external components. The AL8400 linear LED driver controller is priced at $0.18 each/1,000. DIODES INC., Westlake Village, CA. (805) 446-4800.