BCR420UFD

Description

The BCR420UFD and BCR421UFD monolithically integrate transistors, diodes and resistors to function as a Constant Current Regulator (CCR) for linear LED driving. The device regulates with a preset 10mA nominal that can be adjusted with an external resistor up to 350mA. It is designed for driving LEDs in strings and will reduce current at increasing temperatures to self-protect. Operating as a series linear CCR for LED string current control, it can be used in multiple applications, as long as the maximum supply voltage to the device is < 40V.

With the low-side control, the BCR421UFD has an Enable (EN) pin which can be pulse-width modulated (PWM) up to 25kHz by a microcontroller for LED dimming.

With no need for additional external components, this CCR is fully integrated into a 2x2x0.6mm package (U-DFN2020-6) minimizing PCB area, off-board height, and component count.

Feature(s)

• LED Constant Current Regulator Using NPN Emitter-Follower with Emitter Resistor to Current Limit
• I_OUT – 10mA ±10% Constant Current (Preset)
• I_OUT up to 350mA Adjustable with an External Resistor (BCR421U)
• V_OUT – 40V Supply Voltage
• P_D up to 1.7W in U-DFN2020-6 Package
• 6mm Height for Low-Profile Edge Lighting
• Low-Side Control Enabling PWM Input < 25kHz (BCR421U)
• Negative Temperature Coefficient (NTC) Reduces I_OUT with Increasing Temperature
• Parallel Devices to Increase Regulated Current
• Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
• Halogen and Antimony Free. “Green” Device (Note 3)
• Automotive-compliant parts are available under separate datasheet (BCR420UFDQ/BCR421UFDQ)

Application(s)

Constant Current Regulation (CCR) in:

• • Edge lighting strips
  • Emergency lighting
  • Signage, advertising, and decorative/architectural lighting
  • Retail lighting in fridges, freezer cases, and vending machines