ISSI IS32LT3952-GRLA3-EB | Demoboard IS31LT3952_IS32LT3952 DEMO BOARD

Description

The IS31LT3952_IS32LT3952 is a DC-to-DC switchingconverter, which integrate an N-channel MOSFET tooperate in a buck configuration. The device supply awide input voltage between 4.5V and 38V andprovides a constant current of up to 1.5A for driving asingle LED or multiple series connected LEDs.The external resistor, RSET, is used to adjust LEDoutput current, which allowing the output voltage to beautomatically adjusted for a variety of LEDconfigurations.The IS31LT3952_IS32LT3952 operates in a fixedfrequency mode during switching. There is an externalresistor connected between the VCC and TON pinsused to configure the on-time (switching frequency).The switching frequency is dithered for spreadspectrum feature to spread the electromagneticemitting energy into a wider frequency band. It ishelpful to optimize the EMI performance.A logic input PWM signal to the enable (EN) pin isapplied to adjust the LED current. The brightness ofLED is proportional to the duty cycle of the PWMsignal.True average output current operation is achieved withfast transient response by using cycle-by-cycle,controlled on-time method.IS31LT3952_IS32LT3952 is available in an SOP-8-EPpackage with an exposed pad for enhanced thermaldissipation. It operates from 4.5V to 38V over thetemperature range of -40°C to +125°C.

Features

• Wide input voltage supply from 4.5V to 38V
  • Withstand 40V load dump
• ±5% true average output current control
• 1.5A maximum output over operating temperature range
• Cycle-by-cycle current limit
• Integrated high-side MOSFET switch
• Dimming via direct logic input or power supply voltage
• Internal control loop compensation
• Under-voltage lockout (UVLO) and thermal shutdown protection
• 2μA low power shutdown
• Spread spectrum to optimize EMI
• Robust fault protection:
• Pin-to-GND short
• Component open/short faults
• Adjacent pin-to-pin short
• LED open/short
• AEC-Q100 qualification IS32LT3952 only

Typical applications

• Automotive and avionic lighting / Daytime running lights / Turn/stop lights / Front and rear fog lights / Map light
• Dimmable interior lights

More information

• IC product information