特點
Up to 80% Efficiency
Inherently Matched LED Current
Drives Five White LEDs from 2V
Drives Six White LEDs from 2.7V
Drives Eight White LEDs from 3V
Adjustable Control of LED Current
Disconnects LEDs In Shutdown
1.2MHz Fixed Frequency Switching
Uses Tiny Ceramic Capacitors
Uses Tiny 1mm-Tall Inductors
Regulates Current Even When V
IN
> V
OUT
Operates with V
IN
as Low as 1V
Low Profile (1mm) ThinSOT? Package
典型應用
典型應用
描述
With an input voltage range of 1V to 10V, the device works from a variety of input sources. The LT1932 accurately regulates LED current even when the input voltage is higher than the LED voltage, greatly simplifying battery-powered designs. A single external resistor sets LED current between 5mA and 40mA, which can then be easily adjusted using either a DC voltage or a pulse width modulated (PWM) signal. When the LT1932 is placed in shutdown, the LEDs are disconnected from the output, ensuring a quiescent current of under 1μA for the entire circuit. The device’s 1.2MHz switching frequency permits the use of tiny, low profile chip inductors and capacitors to minimize footprint and cost in space-conscious portable applications.