Diodes Inc. introduced a family of LED driver ICs said to be capable of significantly reducing the number and size of external components required by driver circuits. The AP880X step-down dc-dc converters require the support of only four components and operate at switching frequencies up to 600kHz, which enables the use of smaller, lower cost inductors and capacitors.
Designed to drive series-connected LEDs with a constant current, the AP880X family supports up to 13 LEDs from voltage sources between 8 and 48V. The drivers are suitable for a broad range of high-brightness, general illumination applications, including signage, architectural, emergency lighting and MR16 lamp replacement, ensuring uniform LED brightness as well as eliminate the need for ballast resistors.
For an operating voltage range from 8 to 28V, the AP8800 furnishes a string of seven LEDs with a current up to 350mA, providing what is described as a cost effective match for 1W LED systems. For higher output power, the AP8801 produces a drive current of 500mA from an operating voltage of 8 to 48V to support up to 13 series-connected LEDs.
The third product in the driver family, the AP8802, meets the requirements of high power 3W LED systems. For an operating voltage range from 8 to 48V, the AP8802 driver provides up to 13 LEDs with a constant LED current of up to 1A. All three devices deliver efficiencies up to 92%.
To reduce the stress on LEDs, the AP880X drivers feature an integrated soft-start function, which helps to extend LED lifetime. The drivers also offer the choice of PWM and DC input dimming control in order to increase design flexibility.
All devices are packaged in the industry standard SOP-8L package. The AP8800 and AP8801 are also available in MSOP-8L and the AP8802 in exposed pad DFN and SOP-8L packages.