Diodes AP8803 User Manual
Ap8803, Description, Features
AP8803
Document number: DS31970 Rev. 5 - 2
1 of 10
August 2012
© Diodes Incorporated
AP8803
30V 1A BUCK LED DRIVER
Description
The AP8803 is a step-down DC/DC converter designed to drive LEDs
with a constant current. The device can drive up to 7 LEDs,
depending on the forward voltage of the LEDs, in series from a
voltage source of 8V to 30V. Series connection of the LEDs provides
identical LED currents resulting in uniform brightness and eliminating
the need for ballast resistors. The AP8803 switches at frequency up
to 700kHz. This allows the use of small size external components,
hence minimizing the PCB area needed.
Maximum output current of AP8803 is set via an external resistor
connected between the V
IN
and SET input pins. Dimming is achieved
by applying either a DC voltage or a PWM signal at the CTRL input
pin. An input voltage of 0.2V or lower at CTRL shuts down the output
at SW and puts the device into a low-current standby state.
Features
• LED Driving Current up to 1A
• High Efficiency Up to 92%
• Operating Input Voltage Up to 30V
• High Switching Frequency Up to 700kHz
• PWM/DC Input for Dimming Control
• Built-In Output Open-Circuit Protection
• TSOT25: Available in “Green” Molding Compound (No Br, Sb)
with lead Free Finish/ RoHS Compliant
Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
Halogen and Antimony Free. “Green” Device (Note 3)
Pin Assignments
1
2
3
4
5
SET
V
IN
CTRL
GND
SW
Top View
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. Se 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.
Typical Applications Circuit
L1
R
SET
C1
AP8803
CTRL
V
IN
SET
SW
GND
12V_DC