Because of the hysteretic control function of the IC, a constant output current to the LED string is maintained at all times, thereby improving the reliability and lifetime of the LEDs. LED brightness is achieved through a PWM control signal. The IC drives loads of up to 1.0A at over 90% efficiency from input voltages ranging from 4.5 to 40V.
“By accurately delivering a consistent current to LEDs in automotive applications, the AT9919 ensures consistent brightness and prolongs LED lifetimes,” states Stephen Lin, Vice President of Marketing for Supertex. “The IC is available in a compact DFN package, and its high switching frequency reduces the need for many external components, which reduces both the size and the cost of the assembly.”
The AT9919 is available in an eight- lead DFN package (AT9919K7-G). The part is RoHS compliant. Samples are available from stock. Pricing is US$0.98 each for the AT9919K7-G in 1K quantities.