SANTA CLARA, USA: National Semiconductor Corp. has introduced the industry's first high-side light-emitting diode (LED) driver that enables dual LED operation for the camera flash function in portable, battery-powered multimedia devices.
The LM3554, a member of National's PowerWise energy-efficient product family, drives one or two high-current LEDs for flash applications in handheld devices such as mobile phones, smartphones and portable scanners.
Traditional LED flash drivers sink current from a single high-current LED back into the driver resulting in significant heat dissipation into the driver IC and reduced system reliability. The LM3554's dual LED, high-side current-drive architecture sources regulate current into two LEDs with cathodes connected directly to the ground.
This ground connection provides more effective thermal dissipation while minimizing routing complexity and protecting sensitive circuitry. Due to nonlinearity of LED light output versus LED current, the dual LED architecture consumes less power for the same light output as a single LED.
In addition, monitoring pins enable detection of other high current demands in the system, adaptively throttling the LED current to avoid drawing excessive battery current, which can cause faults or harm the system.
The LM3554 is offered in a 16-pin micro SMD package. A complete boost converter solution for LED flash using National's LM3554 measures less than 23sq. mm.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.