LT1932

VIN Voltage ................................................................. 10V
SHDN Voltage .............................................................. 10V
SW Voltage ................................................................. 36V
LED Voltage ................................................................ 36V
RSET Voltage ................................................................ 1V
Junction Temperature ............................................ 125°C
Operating Temperature Range (Note 2) .. 40°C to 85°C
Storage Temperature Range ................. 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................... 300°C


Description

The LT®1932 is a fixed frequency step-up DC/DC converter designed to operate as a constant-current source. Because it directly regulates output current, the LT1932 is ideal for driving light emitting diodes (LEDs) whose light intensity is proportional to the current passing through them, not the voltage across their terminals. 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 batterypowered 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 1mA 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.