BCR421UW6Q Datasheet, PDF (1/11 Pages) Diodes Incorporated – Linear LED Constant Current Regulator in SOT26

BCR421UW6Q
Linear LED Constant Current Regulator in SOT26
Description
This Linear LED driver is designed to meet the stringent requirements
of automotive applications.
The BCR421U monolithically integrates transistors, diodes and
resistors to function as a Constant Current Regulators (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 BCR421U has an Enable (EN) pin
which can be pulse-width modulated (PWM) up to 10 kHz by a micro-
controller for LED dimming.
Features
 LED Constant Current Regulator using NPN Emitter-Follower with
Emitter Resistor to Current Limit
 IOUT – 10mA ± 10% Constant Current (Preset)
 IOUT up to 350mA Adjustable with an External Resistor
 VOUT – 40V Supply Voltage
 PD up to 1W in SOT26 (SC-74)
 Low-Side Control Enabling PWM Input < 10kHz
 Negative Temperature Coefficient (NTC) Reduces IOUT 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)
 Qualified to AEC-Q101 Standards for High Reliability
 PPAP Capable (Note 4)
With no need for additional external components, this CCR is fully
integrated into an SOT26 minimizing PCB area and component count.
Applications
Constant Current Regulation (CCR) in:
 Automotive Interior Lighting
 Mood and Decorative Lighting
Mechanical Data
 Case: SOT26 (SC-74)
 Case Material: Molded Plastic. “Green” Molding Compound.
UL Flammability Rating 94V-0
 Moisture Sensitivity: Level 1 per J-STD-020
 Terminals: Finish - Matte Tin Plated Leads.
Solderable per MIL-STD-202, Method 208
 Weight: 0.018 grams (Approximate)
SOT26 (SC-74)
EN
OUT
Top View
Rext
(Optional)
GND
Internal Device
Schematic
EN
OUT
OUT
Rext
OUT
GND
Top View
Pin-Out
Pin Name
OUT
EN
REXT
GND
Pin Function
Regulated Output Current
Enable for Biasing
Transistor
External Resistor for
Adjusting Output Current
Power Ground
Ordering Information (Note 5)
Product
BCR421UW6Q-7
Compliance
Automotive
Marking
421
Reel Size (inches)
7
Tape Width (mm)
8
Quantity per Reel
3,000
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
4. Automotive products are AEC-Q101 qualified and are PPAP capable. Refer to http://www.diodes.com/quality/product_compliance_definitions/.
5. For packaging details, go to our website at http://www.diodes.com/products/packages.html.
BCR421UW6Q
Document number: DS38302 Rev. 1 - 2
1 of 11
www.diodes.com
October 2015
© Diodes Incorporated