Data Sheet
150kHz 3A BUCK DC-DC CONVERTER
General Description
The AP3003 series of regulators are fixed frequency
PWM buck (step-down) DC/DC converter, capable of
driving a 3A load with excellent line and load regula-
tion. These regulators include internal frequency com-
pensation and a fixed frequency oscillator so that they
are easy to use. A system adopting AP3003 requires a
minimum number of external components to work.
A standard series of inductors, optimized for use with
the AP3003 series, are available from several manu-
facturers. This feature greatly simplifies the design of
switch-mode power supplies.
These ICs are available in TO-220-5 and TO-263-5
packages.
AP3003
Features
·
·
·
·
·
·
·
·
·
·
3.3V, 5V, 12V Fixed (±4% Tolerance) and Adjust-
able (±3% Tolerance) Output Versions
Guaranteed 3A Output Load Current
150kHz Fixed Frequency Internal Oscillator
Input Voltage Range up to 32V
Requires only 4 external components
High Efficiency up to 90%
Excellent Line and Load Regulation
TTL Shutdown Capability
Low Power Standby Mode, I
Q
Typically 80
µ
A
Built-in Current Limit Protection and Thermal
Shutdown Circuit
Applications
·
·
·
·
LCD Monitor and LCD TV
On-Card DC-DC Converter
DVD Recorder
PDP
TO-220-5
TO-263-5
Figure 1. Package Types of AP3003
Aug. 2008 Rev. 1. 2
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BCD Semiconductor Manufacturing Limited
Data Sheet
150kHz 3A BUCK DC-DC CONVERTER
Pin Configuration
T Package
(TO-220-5)
S Package
(TO-263-5)
AP3003
5
4
3
2
1
ON/OFF
FEEDBACK
GND
OUTPUT
V
IN
Metal Tab GND
5
4
3
2
1
ON/OFF
FEEDBACK
GND
OUTPUT
V
IN
Metal Tab GND
Figure 2. Pin Configuration of AP3003 (Top View)
Pin Description
Pin Number
1
2
3
4
Pin Name
V
IN
OUTPUT
GND
FEEDBACK
Unregulated input voltage
Switch driver output
Ground
Feedback Pin. For fixed version, connect it to system output. For adjustable version,
connect it with an external resistor and capacitor feedback network to program the sys-
tem output voltage
The TTL logic compatible input to control the regulator on or off
Function
5
ON/OFF
Aug. 2008 Rev. 1. 2
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BCD Semiconductor Manufacturing Limited
Data Sheet
150kHz 3A BUCK DC-DC CONVERTER
Functional Block Diagram
ON/OFF
5
1
1.23V
REFERENCE
2.5V
REGULATOR
220
mV
START UP
200
mV
4.4Ω
AP3003
V
IN
+
Bias
Current
2.5V
COMP
Frequency Shift
150KHz
OSC
_
_
COMP
+
FEEDBACK
4
1:100
+
R2
+
_
EA
_
COMP
LATCH
DRIVER
&
INV
2
THERMAL
SHUTDOWN
3
OUTPUT
GND
R1
For 3.3V R1=2.49kΩ
5V
R1=2.49kΩ
12V R1=2.49kΩ
ADJ R1=Open
R2=4.18kΩ
R2=7.57kΩ
R2=21.8kΩ
R2=0Ω
Figure 3. Functional Block Diagram of AP3003
Aug. 2008 Rev. 1. 2
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BCD Semiconductor Manufacturing Limited
Data Sheet
150kHz 3A BUCK DC-DC CONVERTER
Ordering Information
AP3003
-
E1: Lead Free
G1: Green
TR: Tape and Reel
Blank: Tube
Package
T: TO-220-5
S: TO-263-5
ADJ: Adjustable Output
3.3: Fixed Output 3.3V
5.0: Fixed Output 5.0V
12: Fixed Output 12V
AP3003
Circuit Type
Package
Temperature
Range
Part Number
Lead Free
AP3003T-ADJE1
AP3003T-3.3E1
AP3003T-5.0E1
AP3003T-12E1
AP3003S-ADJE1
AP3003S-3.3E1
Green
AP3003T-ADJG1
AP3003T-3.3G1
AP3003T-5.0G1
AP3003T-12G1
AP3003S-ADJG1
AP3003S-3.3G1
AP3003S-3.3TRG1
AP3003S-5.0G1
AP3003S-5.0TRG1
AP3003S-12G1
AP3003S-12TRG1
Marking ID
Lead Free
AP3003T-3.3E1
AP3003T-5.0E1
AP3003T-12E1
Green
AP3003T-3.3G1
AP3003T-5.0G1
AP3003T-12G1
AP3003T-ADJE1 AP3003T-ADJG1
Packing
Type
Tube
Tube
Tube
Tube
Tube
Tube
Tape & Reel
Tube
Tape & Reel
Tube
Tape & Reel
TO-220-5
-40 to 85
o
C
AP3003S-ADJE1 AP3003S-ADJG1
AP3003S-3.3E1
AP3003S-3.3E1
AP3003S-5.0E1
AP3003S-5.0E1
AP3003S-12E1
AP3003S-12E1
AP3003S-3.3G1
AP3003S-3.3G1
AP3003S-5.0G1
AP3003S-5.0G1
AP3003S-12G1
AP3003S-12G1
AP3003S-ADJTRE1 AP3003S-ADJTRG1 AP3003S-ADJE1 AP3003S-ADJG1 Tape & Reel
AP3003S-3.3TRE1
AP3003S-5.0E1
AP3003S-5.0TRE1
AP3003S-12E1
AP3003S-12TRE1
TO-263-5
-40 to 85
o
C
BCD Semiconductor's Pb-free products, as designated with "E1" suffix in the part number, are RoHS compliant. Products with
"G1" suffix are available in green packages.
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BCD Semiconductor Manufacturing Limited
Data Sheet
150kHz 3A BUCK DC-DC CONVERTER
Absolute Maximum Ratings (Note 1)
Parameter
Input Voltage
ON/OFF Pin Voltage
Feedback Pin Voltage
Operating Junction Temperature
Thermal Resistance
(Junction to Ambient, No Heatsink)
Lead Temperature (Soldering, 10sec)
Storage Temperature Range
Symbol
V
IN
V
ON/OFF
V
FB
T
J
Value
40
40
40
150
Unit
V
V
V
o
C
AP3003
TO-220-5
R
θJA
60
260
-65 to 150
o
C/W
TO-263-5
T
LEAD
T
STG
o
C
o
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 Max-
imum Ratings" for extended periods may affect device reliability.
Recommended Operating Conditions
Parameter
3.3V
5.0V
Maximum Input Voltage (Note 2)
12V
ADJ (V
OUT
=3.2V)
ADJ (V
OUT
=2.5V)
Operating Junction Temperature
T
J
V
IN
Symbol
Value
32
32
32
32
25
-40 to 125
o
C
Unit
V
Note 2: For ADJ version, the recommended supply voltage depends on the needed output voltage.
Aug. 2008 Rev. 1. 2
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BCD Semiconductor Manufacturing Limited
