Description
The AL5817 is an 8-terminal adjustable linear LED driver-controller
offering excellent temperature stability and output current capability. It
works with a wide input voltage range from 4.5V to 60V. With an
external LED driving power device, its internal power dissipation is
minimized compared with traditional linear LED drivers. This makes it
ideal for medium to high current LED circuits.
The AL5817 has internal output drive capability up to 15mA, which
enables it to drive external Bipolar transistors or MOSFETs. It also
provides the capability to drive longer LED chains with low drop out
voltage and multiple LED channels.
The VSET pin is used to directly set output current feedback level.
Using a resistor divider between REF pin and VSET pin, the output
current can be set. Additionally, the use of an NTC resistor allows the
creation of an accurate and configurable thermal fold-back behavior.
The AL5817 provides an LED-open detection feature through its
VFAULT pin. If VFAULT is brought lower than 2.5V (by any one of the
multiple LED channels going open) the AL5817’s output will go low
turning off the external transistors. The device will recover when the
open condition is removed. This ability of VFAULT to turn off the
external transistors also allows PWM dimming of the LED current by
adding PWM control signal on VFAULT pin.
An enable pin ENB is available to externally turn on and off the LEDs.
The AL5817 is available in the thermally enhanced MSOP-8EP
package.
AL5817
60V LINEAR DIMMABLE LED CONTROLLER
Pin Assignments
(Top View)
VCC
REF
VSET
GND
1
2
3
4
EP
8 VFAULT
7 ENB
6 OUT
5 FB
MSOP-8EP
Applications
Automotive Rear Combination Light
LED Signs
Instrumentation Illumination
Refrigerator Lights
Features
Wide Input Voltage Range from 4.5V to 60V
Configurable LED Current Setting
4% Reference Voltage Tolerance
Low Temperature Drift
15mA Output Drive Capability for MOSFET or Bipolar Transistor
LED Open Protection Detected by VFAULT Pin
LED Thermal Fold-back Configured by VSET
Over Temperature Protection (OTP)
Input Under Voltage Lock-Out
PWM Dimming Realized Through VFAULT Pin or ENB Pin
Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant.
2. See https://www.diodes.com/quality/lead-free/ 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.
AL5817
Document number: DS40391 Rev. 3 - 2
1 of 13
www.diodes.com
August 2018
© Diodes Incorporated
