IS31LT3178数据手册开发板套件编程器的评估板-LED驱动器规格书PDF

描述 Description

The IS31LT3177 and IS31LT3178 are adjustable linear current devices with excellent temperature stability. A single resistor is all that is required to set the operating current from 10mA to 200mA. The devices can operate from an input voltage from 2.9V to 40V with a minimal voltage headroom of 1.0V (Typ.) at 150mA. Designed with a low dropout voltage; the device can drive LED strings close to the supply voltage without switch capacitors or inductors.

The IS31LT3177/78 simplifies designs by providing a stable current without the additional requirement of inductors, FETs or diodes. The complete constant current driver requires only a current set resistor and a small PCB area making designs both efficient and cost effective.

The EN Pin of the IS31LT3177 can be tied to VBAT or PSM (Power Supply Modulation) signal for high side dimming. The EN Pin of the IS31LT3178 can function as the PWM signal input used for MCU PWM dimming.

As a current sink it is ideal for LED lighting applications or current limiter for power supplies.

The device is provided in a lead (Pb) free, SOT23-6 and SOP-8-EP packages.

特性 Features

• Low-side current sink ▪ Adjustable from 10mA to 150mA (SOT23-6)/200mA (SOP-8-EP) with external resistor selection
• Wide input voltage range from below voltage with a low dropout of typical 1.0V at 150mA ▪ 2.9V to 40V (IS31LT3178) ▪ 5V to 40V (IS31LT3177)
• Up to 1kHz PWM input (IS31LT3178 only)
• ±5% current accuracy
• Protection features: ▪ 0.6%/K current roll off at high temp over 145°C for thermal protection ▪ Output current limit ▪ Thermal shutdown
• Up to 0.77W (SOT23-6)/2.32W (SOP-8-EP) power dissipation in a small package
• RoHS compliant (Pb-free) package

应用 Application

• General lighting
• Architectural LED lighting
• Channel letters for advertising, LED strips for decorative lighting
• Retail lighting in fridge, freezer case and vending machines
• Emergency lighting (e.g. steps lighting, exit way sign etc.)