Diodes AP1512A-33K5L-U 50khz, 2a/3a pwm buck dc/dc converter Datasheet

AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
General Description
Features
•
•
•
•
•
•
•
•
•
•
•
Output voltage: 3.3V, 5V, 12V and adjustable output
version
Adjustable version output voltage range, 1.23V to
37V+4%
50KHz +15% fixed switching frequency
Voltage mode non-synchronous PWM control
Thermal-shutdown and current-limit protection
ON/OFF shutdown control input
Operating voltage can be up to 60V
Output load current: 2A (for AP1512)
3A (for AP1512A)
Low power standby mode
Built-in switching transistor on chip
Lead Free Finish/ RoHS Compliant (Note 1)
The AP1512/A is a monolithic IC designed for use as a
step-down DC/DC converter with the ability of driving a 2A (3A for
AP1512A) load without additional transistor components. The
board space is reduced since AP1512/A requires few external
components. The external shutdown function is controlled by
logic level and can be put into standby mode. The internal
compensation ensures feedback control has good line and load
regulation without external design. Both an integrated Thermal
shutdown and Current Limit function are provided to prevent
damage from exceeding temperature operation and against
exceeding the current operating of the output switch. The
AP1512/A operates at a switching frequency of 50KHz thus
allowing smaller sized filter components than what would be
needed with lower frequency switching regulators. Other features
include a guaranteed +4% tolerance on output voltage under
specified input voltage and output load conditions, and +15%
tolerance on the oscillator frequency. The AP1512/A offers fixed
output voltages of 3.3V, 5V, 12V, plus Adjustable. The package is
available in a standard 5-lead TO263 package.
Applications
•
•
•
Simple High-efficiency step-down regulator
On-card switching regulators
Positive to negative converter
Ordering Information
AP1512 X - XX XX X X
Output Version
Part Number
Blank : 2A
A : 3A
Lead-free
Blank : Adjustable
33 : 3.3V
50 : 5.0V
12 : 12V
Device
Package
Code
Packaging
(Note 2)
AP1512X-XXK5
K5
TO263-5L
Notes:
Package
K5 : TO263-5L
Lead Free
Packing
L : Lead Free -U : Tube
-13 : Tape & Reel
Tube
Part Number
Quantity
Suffix
50
-U
13” Tape and Reel
Part Number
Quantity
Suffix
800/Tape & Reel
-13
1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied, see EU Directive 2002/95/EC Annex Notes.
2. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at
http://www.diodes.com/datasheets/ap02001.pdf.
AP1512/A Rev. 4
1 of 12
www.diodes.com
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Pin Descriptions
Pin Assignments
( Top View )
Name
5 SD
4 FB
3 GND
2 Output
1 VIN
Description
VIN
Operating voltage input
Output
GND
Metal Tab GND
TO263-5L
Switching output
Ground
FB
Output voltage feedback control
SD
ON/OFF Shutdown
Block Diagram
SD
VIN
200mV
Current
Source
bias
1.235V
Reference
2.5V
Regulator
220mV
Start
up
+
Comp
_
_
Comp
+
FB
_
Amp
Frequecy
compensation
_
+
Comp
+
Pre-driver
2A
Switch
(3A for
AP1512A)
Output
50KHz
OSC.
AP1512/A Rev. 4
2 of 12
www.diodes.com
Thermal
Limit
Gnd
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Absolute Maximum Ratings
Symbol
ESD HBM
ESD MM
VCC
VSD
VFB
VOUT
TST
TJ
VOP
Parameter
Human Body Model ESD Protection
Machine Model ESD Protection
Supply Voltage
ON/OFF Pin Input Voltage
Feedback Pin Voltage
Output Voltage to Ground
Storage Temperature
Operating Junction Temperature
Operating Voltage
Rating
4.5
450
+63
-0.3 to +40
-0.3 to +40
-1
-65 to +150
-40 to +125
+4.5 to +60
Unit
KV
V
V
V
V
V
o
C
o
C
V
Recommended Operating Conditions
Symbol
VIN
IOUT
TA
AP1512/A Rev. 4
Parameter
Input Voltage
Output Current
Operating Ambient Temperature
3 of 12
www.diodes.com
Min
4.5
0
-20
Max
60
2
85
Unit
V
A
o
C
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Electrical Characteristics
(All Output Voltage Versions)
Unless otherwise specified, VIN = 30V for all version. ILOAD = 0.5A
Specifications with boldface type are for full operating temperature range, the other type are for TA = 25ºC.
Symbol
IB
FOSC
VSAT
DC
ICL
ICL
IL
IQ
ISTBY
VIL
VIH
IH
IL
Parameter
Feedback Bias Current
Conditions
Min
VFB = 1.3V
(Adjustable version only)
5
42.5
40
Oscillator Frequency
IOUT = 2A
no outside circuit
VFB = 0V force driver on
Max. Duty Cycle(ON)
VFB = 0V force driver on
Min. Duty cycle(OFF)
VFB = 12V force driver off
peak current
Current Limit for AP1512 no outside circuit
VFB = 0V force driver on
peak current
Current Limit for AP1512A no outside circuit
VFB = 0V force driver on
no outside circuit
Output = 0 Output
VFB = 12V force driver off
leakage
VIN = 60V
Output = -1 current
Quiescent Current
VFB = 12V force driver off
ON/OFF pin = 5V
VIN = 60V
ON/OFF pin logic input
threshold voltage
Low (regulator ON)
High (regulator OFF)
ON/OFF pin logic
VLOGIC = 2.5V (OFF)
input current
ON/OFF pin input current VLOGIC = 0.5V (ON)
θJC
Thermal Resistance
TO263-5L
Junction to case
θJA
Thermal Resistance
With copper area of
approximately 3 in2
TO263-5L
Junction to ambient
AP1512/A Rev. 4
4 of 12
www.diodes.com
50
1.3
Saturation Voltage
Standby Quiescent
Current
Typ.
Max
8
10
57.5
60
1.4
Unit
μA
KHz
V
1.5
100
0
%
4.5
2.5
3
3.2
4
A
5.5
5
-2
5
350
2.0
A
6
-250
uA
-60
10
450
500
mA
mA
1.3
0.6
-
0
-5
-0.8
2.5
3.5
28
-10
uA
V
uA
o
C/W
o
23
C/W
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Electrical Characteristics
(Continued)
AP1512
Symbol
Parameter
Conditions
VMIN
Typ.
VMAX
Unit
Output
Feedback
10V < VIN < 60V
0.2A < ILOAD < 2A
VOUT programmed for 3V
1.193
1.18
1.23
1.267
1.28
V
AP1512-ADJ
VFB
AP1512-3.3V
VOUT
Output voltage
10V < VIN < 60V
0.2A < ILOAD < 2A
3.168
3.135
3.3
3.432
3.465
V
AP1512-5V
VOUT
Output voltage
10V < VIN < 60V
0.2A < ILOAD < 2A
4.8
4.75
5
5.2
5.25
V
VOUT
Output voltage
15V < VIN < 60V
0.2A < ILOAD < 2A
11.52
11.4
12
12.48
12.6
V
Efficiency
VIN = 30V, ILOAD = 2A
AP1512-12V
η
83
%
Specifications with boldface type are for full operating temperature range, the other type are for TA = 25ºC.
AP1512A
Symbol
Parameter
Conditions
VMIN
Typ.
VMAX
Unit
Output
Feedback
10V < VIN < 60V
0.2A < ILOAD
VOUT programmed for 3V
1.193
1.18
1.23
1.267
1.28
V
AP1512A-ADJ
VFB
AP1512A-3.3V
VOUT
Output voltage
10V < VIN < 60V
0.2A < ILOAD
3.168
3.135
3.3
3.432
3.465
V
AP1512A-5V
VOUT
Output voltage
10V < VIN < 60V
0.2A < ILOAD
4.8
4.75
5
5.2
5.25
V
VOUT
Output voltage
15V < VIN < 60V
0.2A < ILOAD
11.52
11.4
12
Efficiency
VIN = 30V, ILOAD = 3A
AP1512A-12V
η
80
12.48
12.6
V
%
Specifications with boldface type are for full operating temperature range, the other type are for TA = 25ºC.
AP1512/A Rev. 4
5 of 12
www.diodes.com
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Typical Performance Characteristics
4
3.9
3.8
3.7
3.6
3.5
3.4
3.3
3.2
3.1
3
-50
AP1512A Efficiency vs. Supply Voltage
( Vout = 5V, Iout = 3A )
Efficiency(%)
Current Limit (A)
AP1512A Current Limit vs. Temperature
( Vcc = 60V, Vout = 5V )
0
50
100
100
90
80
70
60
50
40
30
20
10
0
150
0
12
24
Temperature (TA) (°C)
AP1512 Efficiency vs. Temperature
( Vin = 12V, Vout = 5V, Io = 2A )
90
80
80
Efficiency (%)
100
90
Efficiency (%)
70
60
50
40
30
60
70
60
50
40
30
20
20
10
10
30 50 70
48
AP1512 Efficiency vs. Temperature
( Vin = 12V, Vout = 3.3V, Io = 2A )
100
0
-50 -30 -10 10
36
Supply Voltage(V)
0
-50 -30 -10 10 30
90 110 130 150
Temperature (TA) (°C)
50 70 90 110 130 150
Temperature (TA) (°C)
AP1512 Supply Current vs. Temperature
( Vcc = 12V, No Load, Von/off = 0V (Switch ON), Von/off = 5V (Switch OFF))
100
8
90
6
Supply Current (uA)
Supply Current (mA)
7
Sw itch ON
5
4
3
2
70
60
50
40
30
20
10
1
0
-40 -25 -10 5
20 35 50 65 80 95 110 125
0
-40 -25 -10 5
20 35 50 65 80 95 110 125
Temperature (TA) (°C)
Temperature (TA) (°C)
AP1512/A Rev. 4
Sw itch OFF
80
6 of 12
www.diodes.com
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Typical Performance Characteristics
(Continued)
AP1512 Current Limit vs. Temperature
( Vcc = 60V, Vout = 5V )
60
3.6
55
3.4
Current Limit (A)
Frequency (KHz)
AP1512 Frequency vs. Temperature
( Vcc = 12V, Io = 1A, Vout = 5V )
50
45
40
-50 -30 -10 10
30
50
70
90 110 130 150
3.2
3
2.8
-50
0
50
100
150
Temperature (TA) (°C)
Temperature (TA) (°C)
AP1512 Quiescent Current vs. Supply Voltage
( force driver off )
Quiescent Current (A)
6.2
6
5.8
5.6
5.4
5.2
0
12
24
36
48
60
Supply Voltage(V)
AP1512/A Rev. 4
7 of 12
www.diodes.com
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Typical Application Circuit
(1) Adjustable Type Circuit
A. Vin = 10V~60V, Vout = 5V; Iout = 0.3A~2A, Iout below 0.3A DCM
1
Vin
Vin
OUTPUT
L1
1
2
2
Vout
47uH
AP1512/A
5
C1
C2
100uF/100V
1u
SD
ON/OFF
FB
GND
3
4
R2
3K
D1
B360/B
C5
1n
C7
C3
0.1u
470uF/16V
R3
1K
B. Vin = 10V~60V, Vout = 3.3V, Iout = 0.3A~2A, Iout below 0.3A DCM
1
Vin
Vin
OUTPUT
2
1
L1
2
Vout
47uH
AP1512/A
5
C1
C2
100uF/100V
1u
ON/OFF
SD
GND
3
FB
4
D1
B360/B
R2
2K
C5
1n
C7
C3
0.1u
470uF/16V
R3
1.2K
AP1512/A Rev. 4
8 of 12
www.diodes.com
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Typical Application Circuit
( Continued )
(2) Fixed Type Circuit
A. Vin = 10V~60V, Vout = 5V, Iout = 0.7A~2A, Iout below 0.7A DCM
1
Vin
Vin
OUTPUT
2
1
L1
2
Vout
47uH
AP1512/A
5
C1
C2
100uF/100V
1u
SD
GND
3
ON/OFF
FB
4
D1
B360/B
C7
C3
10n
470uF/16V
B. Vin = 10V~60V, Vout = 3.3V, Iout = 0.7A~2A, Iout below 0.7A DCM
1
Vin
Vin
OUTPUT
2
1
L1
2
Vout
33uH
AP1512/A
5
C1
220uF/100V
AP1512/A Rev. 4
C2
3.3u
ON/OFF
SD
GND
3
FB
4
9 of 12
www.diodes.com
D1
B360/B
C7
3.3u
C3
1500uF/16V
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Functional Description
+VIN
This is the positive input supply for the IC switching regulator. A suitable input bypass capacitor must be present at this pin to minimize
voltage transients and to supply the switching currents needed by the regulator.
Ground
Circuit ground.
Output
Internal switch. The voltage at this pin switches between (+VIN – VSAT) and approximately – 0.5V, with a duty cycle of approximately VOUT /
VIN. To minimize coupling to sensitive circuitry, the PC board copper area connected to this pin should be kept a minimum.
Feedback
Senses the regulated output voltage to complete the feedback loop.
ON/OFF
Allows the switching regulator circuit to be shutdown using logic level signals thus dropping the total input supply current to approximately
150uA. Pulling this pin below a threshold voltage of approximately 1.3V turns the regulator on, and pulling this pin above 1.3V (up to a
maximum of 40V) shuts the regulator down. If this shutdown feature is not needed, the SD pin can be wired to the ground pin or it can
be left open, in either case the regulator will be in the ON condition.
Thermal Considerations
The AP1512/A is available in a 5-pin surface mount TO-263 package.
The TO-263 surface mount package tab is designed to be soldered to the copper on a printed circuit board. The copper and the board
are the heat sink for this package and the other heat producing components, such as the catch diode and inductor. The PC board
2
copper area that the package is soldered to should be at least 0.4 in , and ideally should have 2 or more square inches of 2 oz. Additional
2
copper area improves the thermal characteristics, but with copper areas greater than approximately 6 in , only small improvements in
heat dissipation are realized. If further thermal improvements are needed, double sided, multilayer PC boards with large copper areas
and/or airflow are recommended.
The AP1512/A (TO-263 package) junction temperature rises above ambient temperature with a 2A load for various input and output
voltages. This data was taken with the circuit operating as a buck switching regulator with all components mounted on a PC board to
simulate the junction temperature under actual operating conditions. This curve can be used for a quick check for the approximate
junction temperature for various conditions, but be aware that there are many factors that can affect the junction temperature. When
load currents higher than 2A are used, double sided or multilayer PC boards with large copper areas and/or airflow might be needed,
especially for high ambient temperatures and high output voltages.
For the best thermal performance, wide copper traces and generous amounts of printed circuit board copper should be used in the board
layout. (Once exception to this is the output (switch) pin, which should not have large areas of copper.) Large areas of copper provide
the best transfer of heat (lower thermal resistance) to the surrounding air, and moving air lowers the thermal resistance even further.
Package thermal resistance and junction temperature rise numbers are all approximate, and there are many factors that will affect these
numbers. Some of these factors include board size, shape, thickness, position, location, and even board temperature. Other factors
are, trace width, total printed circuit copper area, copper thickness, single or double-sided, multilayer board and the amount of solder on
the board. The effectiveness of the PC board to dissipate heat also depends on the size, quantity and spacing of other components on
the board, as well as whether the surrounding air is still or moving. Furthermore, some of these components such as the catch diode will
add heat to the PC board and the heat can vary as the input voltage changes. For the inductor, depending on the physical size, type of
core material and the DC resistance, it could either act as a heat sink taking heat away from the board, or it could add heat to the board.
AP1512/A Rev. 4
10 of 12
www.diodes.com
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
Marking Information
(1) TO263-5L
(Top view)
Output Type:
1512: ADJ
1512-33: 3.3V
1512-50: 5.0V
1512-12: 12V
1512X-XX
YY WW X X
Logo
L : Lead Free
Internal code
Xth week: 01~52
Year: "07" = 2007
"08" = 2008
~
Package Information
(All Dimensions in mm)
(1) Package Type: TO263-5L
AP1512/A Rev. 4
11 of 12
www.diodes.com
MAY 2008
© Diodes Incorporated
AP1512/A
50KHz, 2A/3A PWM BUCK DC/DC CONVERTER
IMPORTANT NOTICE
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further
notice to any product herein. Diodes Incorporated does not assume any liability arising out of the application or use of any product described herein; neither
does it convey any license under its patent rights, nor the rights of others. The user of products in such applications shall assume all risks of such use and will
agree to hold Diodes Incorporated and all the companies whose products are represented on our website, harmless against all damages.
LIFE SUPPORT
Diodes Incorporated products are not authorized for use as critical components in life support devices or systems without the expressed written approval of the
President of Diodes Incorporated.
AP1512/A Rev. 4
12 of 12
www.diodes.com
MAY 2008
© Diodes Incorporated
Similar pages