Diodes AP3019A User Manual
WHITE LED STEP-UP CONVERTER AP3019A
Data Sheet
General Description
The AP3019A is an inductor-based DC/DC converter
designed to drive up to eight white LEDs in series for
backlight. Only one feedback resistor is needed to
control the LED current and obtain required
brightness.
A constant frequency 1.2MHz PWM control scheme
is employed in this IC, which means tiny external
components can be used. Specifically, 1mm tall
inductor and 0.22µF output capacitor for a typical
application is sufficient. Additionally, the Schottky
diode in boost circuit is integrated on this chip.
AP3019A also provides a disable pin to ease its use
for different systems.
The output over-voltage protection is implemented in
AP3019A. When any LED is broken or in other
abnormal conditions, the output voltage will be
clamped.
The AP3019A is available in standard SOT-23-6 and
TSOT-23-6 packages.
Features
Inherently Uniform LED Current
•
• High Efficiency up to 84%
• No Need for External Schottky Diode
• Output Over-voltage Protection (OVP)
• Fixed 1.2MHz Switching Frequency
• Uses Tiny 1mm Tall Inductor
• Requires Only 0.22µF Output Capaci t or
Applications
• Cellular Phones
• Digital Cameras
• LCD modules
• GPS Receivers
• PDAs, Handheld Computers
SOT-23-6 TSOT-23-6
Figure 1. Package Types of AP3019A
May. 2010 Rev. 1.8 BCD Semiconductor Manufacturing Limited
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Data Sheet
WHITE LED STEP-UP CONVERTER AP3019A
Pin Configuration
K/KT Package
(SOT-23-6/TSOT-23-6)
Pin 1 Dot by Marking
SW
GND
FB
Figure 2. Pin Configuration of AP3019A (Top View)
1
2
34
V
6
5
IN
V
OUT
CTRL
Pin Description
Pin Number Pin Name Function
1 SW
2 GND
3 FB
4 CTRL
5 V
OUT
6 VIN
Switch pin. Connect external inductor
Ground
Voltage feedback pin. Reference voltage is 200mV
Shutdown and dimming pin. Connect to 1.8V or higher to enable
device; Connect to 0.5V or less to disable device; Connect to a PWM
signal to achieve LEDs brightness dimming
Output pin. Connect to the cathode of internal Schottky diode
Input supply pin. Must be connected to a local bypass capacitor
May. 2010 Rev. 1.8 BCD Semiconductor Manufacturing Limited
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Data Sheet
WHITE LED STEP-UP CONVERTER AP3019A
Functional Block Diagram
Figure 3. Functional Block Diagram of AP3019A
Ordering Information
AP3019A -
Circuit Type
Package
K: SOT-23-6 TR: Tape & Reel
KT: TSOT-23-6
Package
SOT-23-6
Temperature
Range
-40 to 85°C
Part Number Marking ID Packing Type
AP3019AKTR-G1 GAS Tape & Reel
G1: Green
TSOT-23-6
-40 to 85°C
AP3019AKTTR-G1 L8E Tape & Reel
BCD Semiconductor's Pb-free products, as designated with "G1" suffix in the part number, are RoHS compliant
and green.
May. 2010 Rev. 1.8 BCD Semiconductor Manufacturing Limited
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Data Sheet
WHITE LED STEP-UP CONVERTER AP3019A
Absolute Maximum Ratings (Note 1)
Parameter Symbol Value Unit
Input Voltage VIN 20 V
SW Pin Voltage VSW 38 V
Feedback Voltage VFB 20 V
CTRL Pin Voltage V
Thermal Resistance (Junction to
Ambient, No Heat Sink)
Operating Junction Temperature TJ 150
Storage Temperature Range T
Lead T em perature (Soldering, 10sec) T
ESD (Machine Model) 250 V
ESD (Human Body Model) 2000 V
20 V
CTRL
θ
JA
-65 to 150
STG
260
LEAD
265
°C/W
°C
°C
°C
Note 1: Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to
the device. These are stress ratings only, and functional operation of the device at these or any other conditions
beyond those indicated under “Recommended Operating Conditions” is not implied. Exposure to “Absolute
Maximum Ratings” for extended periods may affect device reliability.
Recommended Operating Conditions
Parameter Symbol Min Max Unit
Operating T em perature Range TOP -40 85
Input Voltage VIN 2.5 16 V
CTRL Pin Voltage V
16 V
CTRL
°C
May. 2010 Rev. 1.8 BCD Semiconductor Manufacturing Limited
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Data Sheet
WHITE LED STEP-UP CONVERTER AP3019A
Electrical Characteristics
V
=3V, V
IN
Parameter Symbol Conditions Min Typ Max Unit
Minimum Operating Voltage VIN (min) 2.5
Maximum Operating Voltage VIN (max) 16
Feedback Voltage (Note 2) VFB
FB Pin Bias Current IFB 35 100 nA
Quiescent Current IQ VFB=VIN, no switching 1.5 2.5 3.2 mA
=3V, TA =25°C, unless otherwise specified.
CTRL
=20mA, 4 LEDs,
I
OUT
T
=-40oC to 85oC
A
188 200 212
V
mV
Shutdown Quiescent Current I
V
SHDN
=0V 2.0 4.0 6.0
CTRL
µA
Switching Frequency f 0.9 1.2 1.5 MHz
Maximum Duty Cycle D
90 93 %
MAX
D=40% 550
Switch Current Limit (Note 3) I
LIMIT
mA
D=80% 550
Switch VCE Saturation Voltage V
Switch Leakage Current VSW=5V 0.01 5
ISW=250mA 360 mV
CESAT
µA
High 1.8
CTRL Pin Voltage V
CTRL
V
low 0.5
CTRL Pin Bias Current I
CTRL
100
µA
OVP Voltage VOV 30 V
Schottky Forward Drop V
Schottky Leakage Current
ID=150mA 0.7 V
DROP
VR(reverse voltage)=23V 0.1 4
(reverse voltage)=27V 150
V
R
µA
Soft Start Time t 300
Thermal Resistance
(Junction to Case)
θ
JC
SOT-23-6 60
TSOT-23-6 60
µS
°C/W
Note 2: The bold type specifications of full temperature range are guaranteed by design (GBD).
Note 3: The switch current limit is related to duty cycle. Please refer to Figure 15 for detail.
May. 2010 Rev. 1.8 BCD Semiconductor Manufacturing Limited
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