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Automotive LED drivers

AT9917 and the AT9932 are LED lamp driver ICs that Supertex designed to withstand input voltage transients in solid-state lighting applications in vehicles, such as head lights, tail lights, indicator lights, dome lights, and panel backlights. The AT9917 uses a peak-current-mode control scheme to drive single-switch converters and includes an internal transconductance amplifier to accurately control output current to the LEDs. It also includes a fault output using an external FET, to disconnect the LED string during erroneous conditions, such as an alternator load dump. The AT9932 features a feed forward current control scheme, which achieves very low susceptibility to input voltage transients in automotive LED lighting applications. The IC can maintain constant output current even under vigorous input transient conditions. Its output current control loop is inherently stable and you can compensate it using a single capacitor with the appropriate damping at the coupling capacitor. The ICs come in 24 lead TSSOP packages and cost $2.05/$2.23 (1000).

Supertex, www.supertex.com/Feature_AT9917.html