LT3760 8-channel LED driver circuit.

This Led driver circuit schematic is based on the LT3760 8-channel LED driver circuit which is a step-up DC/DC controller capable of driving up to 45V of LEDs.
Each channel of LT3760 contains an accurate current sink with ±2% current matching. Output current for each channel can be programmed from 20mA to 100mA per string but for higher output LED current the channels can be paralleled .

Micropower DC-DC Converter circuits LT1073

 Features

• No Design Required
• Operates at Supply Voltages From 1.0V to 30V
• Consumes Only 95µA Supply Current
• Works in Step-Up or Step-Down Mode
• Only Three External Off-the-Shelf Components Required
• Low-Battery Detector Comparator On-Chip
• User-Adjustable Current Limit
• Internal 1A Power Switch
• Fixed or Adjustable Output Voltage Versions
• Space-Saving 8-Pin MiniDIP or SO8 Packag

Typical Application

Description

The LT1073 is a versatile micropower DC/DC converter. The device requires only three external components to deliver a fixed output of 5V or 12V. The very low minimum supply voltage of 1V allows the use of the LT1073 in applications where the primary power source is a single cell. An on-chip auxiliary gain block can function as a low-battery detector or linear post-regulator. Average current drain of the LT1073-5 used as shown in the Typical Application circuit below is just 135µA unloaded, making it ideal for applications where long battery life is important. The circuit shown can deliver 5V at 40mA from an input as low as 1.25V and 5V at 10mA from a 1V input.
The device can easily be configured as a step-up or step-down converter, although for most step-down applications or input sources greater than 3V, the LT1173 is recommended. Switch current limiting is user-adjustable by adding a single external resistor. Unique reverse-battery protection circuitry limits reverse current to safe, nondestructive levels at reverse supply voltages up to 1.6V.

Applications

• Pagers
• Cameras
• Single-Cell to 5V Converters
• Battery Backup Supplies
• Laptop and Palmtop Computers
• Cellular Telephones
• Portable Instruments
• 4mA-20mA Loop Powered Instruments
• Hand-Held Inventory Computers
• Battery-Powered Alpha, Beta and Gamma Particle Detectors

Electronics Circuit Application

3Vdc to 12Vdc step up DC converte circuits.

The 3Vdc to 12Vdc step up DC converter by IC LT1073-12,