IS32LT3125/3125A SINGLE CHANNEL 250mA LED DRIVER WITH FAULT DETECTION June 2020 GENERAL DESCRIPTION FEATURES The IS32LT3125/3125A is a linear programmable Single channel, sources up to 250mA current regulator consisting of a single output channel 5.0V to 28V input supply voltage range capable of 250mA. It features an EN pin to enable and - Withstand 42V load dump disable the output channels current source. It supports External resister sets source current PWM dimming via EN pin or power supply modulation Programmable VCC undervoltage lockout to (PSM). The UV pin can be used to set external VCC undervoltage lockout threshold via a resistor divider. match the LED stack for High Side PWM operation An external resistor programs the current level for the Shared fault flag for multiple devices operation channel current source. In addition, Fault protection with flag output: IS32LT3125/3125A integrates fault protection for LED - LED string open/short open/short, ISET pin open/short and over temperature - OUT pin short to VCC/GND condition for robust operation. Detection of these - ISET pin open/short failures is reported by the FAULTB pin. When a fault is - Thermal shutdown detected the device will disable itself and output an - I set to 30mA under fault condition CC open drain low signal. Multiple devices can have their (IS32LT3125 only) FAULTB pins connected to create a one-fail-all-fail condition. Under a fault condition, the IS32LT3125 will External C capacitor keeps fault status during STOR sink 30mA I current, while the IS32LT3125A will sink start/stop operation CC a lower 2mA (Max.) I . CC SOP-8-EP package AEC-Q100 Qualified The IS32LT3125/3125A is targeted at the automotive Operating temperature range from -40C ~ +125C market with end applications to include interior and exterior lighting. For 12V automotive applications the low dropout driver can support one to several LEDs on APPLICATIONS the output channel. Automotive interior/exterior lighting: Both devices are offered in a small thermally enhanced - Turn signal light SOP-8-EP package. - Tail/stop light - Position light - Dome light TYPICAL APPLICATION CIRCUIT Figure 1 Typical Application Circuit Lumissil Microsystems www.lumissil.com 1 Rev.A, 06/08/2020 IS32LT3125/3125A Figure 2 Typical Application Circuit (Several Devices in Parallel with FAULTB Interconnection) Note 1: For PSM dimming application, high C capacitor value will affect the dimming accuracy. To get better dimming performance, VCC recommend 0.1F for it. Lumissil Microsystems www.lumissil.com 2 Rev.A, 06/08/2020