AL5871

Description

The AL5871 is a single-channel linear LED driver with PWM (pulsewidth modulation) and analog dimming control. The AL5871 can drive up to 750mA and the LED current can be set by the low-power reference resistor connected to the REF pin.

The AL5871 regulates LED current accurate to ±4%, with excellent PWM and analog dimming performance. The AL5871 enters standby mode to save power if no PWM signal is detected.

The AL5871 monitors the temperature and reduces the LED current if the chip temperature exceeds the threshold temperature. And the input undervoltage lockout (UVLO), LED string open/short protection, and overtemperature protection (OTP) are designed for applications to improve system robustness. The FAULTB pin is pulled low if any protection is triggered.

The AL5871 is a simple solution to deliver constant current for a single LED string with one-fail-all-fail function, and can work with AL5873 to address different requirements. The AL5871 is available in the TSSOP-16EP (Type DX) package.

Feature(s)

• Wide Input Voltage Range from 5V to 55V
• Up to 750mA Output Current Capacity
• Low-Dropout Voltage on LED Pin
• Output Current Adjustable by a Low-Power External Reference Resistor
• PWM and Analog Dimming with Excellent Linearity
• Automatically Enter and Exit Standby Mode Without Enable Pin
• Internal Protections:
  • Input Undervoltage Lockout (UVLO)
  • Enable LED String Open Protection
  • LED String Short Protection
  • Overtemperature Protection (OTP)
• Diagnostic Enable with Adjustable Threshold for Low-Dropout Operation
• Thermal Foldback If Chip Temperature Exceeds the Threshold
• Fault Reporting: UVLO, OTP, LED Open, and LED Short
• Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
• Halogen and Antimony Free. “Green” Device (Note 3)
• An automotive-compliant part is available under separate datasheet (AL5871Q)

Application(s)

• Interior lighting: dome lights, reading lamps
• Exterior lighting:
  • Small lights: blind-spot detection indicators, charging inlets, door handles
  • Rear lights: rear lamps, center high mounted stop lamps, side markers