AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of
this product. No rights under any patent accompany the sale of the product.
Rev.1.1 Oct. 14, 2005
1/12
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
- TO220-5L, TO220-5L(R) and TO263-5L Pb-free
packages
Applications
- Simple High-efficiency step-down regulator
- On-card switching regulators
- Positive to negative converter
General Description
The AP1512/A is a monolithic IC that design for a
step-down DC/DC converter, and own the ability of
driving a 2A (3A for AP1512A) load without
additional transistor component. Due to reducing
the number of external component, the board
space can be saved easily. The external shutdown
function can be controlled by logic level and then
come into standby mode. The internal
compensation makes feedback control have good
line and load regulation without external design.
Regarding protected function, thermal shutdown is
to prevent over temperature operating from damage,
and current limit is against over 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% on the oscillator
frequency. The output version included fixed 3.3V,
5V, 12V, and an adjustable type. The packages are
available in a standard 5-lead TO-220 package and
a 5-lead TO-263.
Pin Assignments
TO220-5L
( Top View )
( Top View )
TO263-5L
1 V
IN
5 SD
4 FB
3 Gnd
2 Output
Metal Tab GND
1 V
IN
5 SD
4 FB
3 Gnd
2 Output
Pin Descriptions
Name Description
VIN Operating voltage input
Output Switching output
Gnd Ground
FB Output voltage feedback control
SD ON/OFF Shutdown
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
2/12
Ordering Information
Package
T5: TO220-5L
K5: TO263-5L
Output Version
AP1512 X XX X X
Packing
Blank : Tube
A : Taping
Blank : Adjustable
-33 : 3.3V
-50 : 5.0V
-12 : 12V
T5R: TO220-5L(R)
Part Number
Blank: 2A
A : 3A
Block Diagram
Current
Source
bias
1.235V
Reference
2.5V
Regulator
50KHz
OSC.
Start
up
+
+
_
+
_
Thermal
Limit
Pre-driver
Comp
Comp
Gnd
Output
VIN
SD
FB
220mV
200mV
2A
Switch
+
_
_
Amp Comp
Frequecy
compen-
sation (3A for
AP1512A)
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
3/12
Absolute Maximum Ratings
Symbol Parameter Rating Unit
VCC Supply Voltage +63 V
VSD ON/OFF Pin input voltage -0.3 to +40 V
VFB Feedback Pin voltage -0.3 to +40 V
VOUT Output voltage to Ground -1 V
PD Power dissipation Internally limited W
TST Storage temperature -65 to +150 oC
TOP Operating temperature -40 to +125 oC
VOP Operating voltage +4.5 to +60 V
Electrical Characteristics (All Output Voltage Versions)
Unless otherwise specified, VIN=30V for all version. ILOAD = 0.5A
Symbol Parameter Conditions Min. Typ. Max. Unit
8
IB Feedback bias current VFB=1.3V
(Adjustable version only) 5
10 µA
42.5 50 57.5
FOSC oscillator frequency 40 60
KHz
1.4
VSAT saturation voltage
IOUT=2A
no outside circuit
VFB=0V force driver on
1.3
1.5 V
Max. Duty Cycle(ON) VFB=0V force driver on 100
DC Min. Duty cycle(OFF) VFB=12V force driver off 0 %
4.5
ICL current limit for AP1512
peak current
no outside circuit
VFB=0V force driver on
2.5 3 5.5 A
5
ICL current limit for AP1512A
peak current
no outside circuit
VFB=0V force driver on
3.2 4 6
A
Output = 0 no outside circuit
VFB=12V force driver off -250 uA
IL
Output = -1
Output
leakage
current VIN=60V -2 -60 mA
IQ Quiescent Current VFB=12V force driver off 5 10 mA
450
ISTBY Standby Quiescent
Current
ON/OFF pin=5V
VIN=60V 350
500 uA
VIL Low (regulator ON) - 0.6
VIH
ON/OFF pin logic input
threshold voltage High (regulator OFF) 2.0 1.3 - V
IH ON/OFF pin logic
input current VLOGIC=2.5V (OFF) 0 -5
IL ON/OFF pin input current VLOGIC=0.5V (ON) -0.8 -10
uA
TO220-5L 2.5
θJC Thermal Resistance TO263-5L
Junction to
case 3.5
oC/W
TO220-5L 28
θJA
Thermal Resistance
With copper area of
approximately 3 in2 TO263-5L
Junction to
ambient 23
oC/W
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
4/12
Electrical Characteristics (Continued)
AP1512
Symbol Parameter Conditions Typ. Limit Unit
AP1512-ADJ FB
V Output
Feedback
10V < VIN < 60V
0.2A < ILOAD < 2A
VOUT programmed for 3V
1.23
1.193/1.18
1.267/1.28
V
VMIN
VMAX
AP1512-3.3V OUT
V Output voltage 10V < VIN < 60V
0.2A < ILOAD < 2A 3.3 3.168/3.135
3.432/3.465
V
VMIN
VMAX
AP1512-5V OUT
V Output voltage 10V < VIN < 60V
0.2A < ILOAD < 2A 5 4.8/4.75
5.2/5.25
V
VMIN
VMAX
OUT
V Output voltage 15V < VIN < 60V
0.2A < ILOAD < 2A 12 11.52/11.4
12.48/12.6
V
VMIN
VMAX
AP1512-12V
η Efficiency VIN = 30V, ILOAD = 2A 83 %
AP1512A
Symbol Parameter Conditions Typ. Limit Unit
AP1512A-ADJ FB
V Output
Feedback
10V < VIN < 60V
0.2A < ILOAD
VOUT programmed for 3V
1.23
1.193/1.18
1.267/1.28
V
VMIN
VMAX
AP1512A-3.3V OUT
V Output voltage 10V < VIN < 60V
0.2A < ILOAD 3.3 3.168/3.135
3.432/3.465
V
VMIN
VMAX
AP1512A-5V OUT
V Output voltage 10V < VIN < 60V
0.2A < ILOAD 5 4.8/4.75
5.2/5.25
V
VMIN
VMAX
OUT
V
Output voltage 15V < VIN < 60V
0.2A < ILOAD 12 11.52/11.4
12.48/12.6
V
VMIN
VMAX
AP1512A-12V
η Efficiency VIN = 30V, ILOAD = 3A 80 %
Specifications with boldface type are for full operating temperature range, the other type are for TJ=25ºC.
Typical Performance Characteristics
AP1512A Current Limit v.s. Temperature
(Vcc=60V, Vout=5V)
3
3.2
3.4
3.6
3.8
4
-50 0 50 100 150
Temperature (TA) (°C)
Current Limit (A)
AP1512A Efficiency v.s. Supply Voltage
(Vout=5V, Iout=3A)
0
10
20
30
40
50
60
70
80
90
100
0 1224364860
Supply Voltage(V)
Efficiency(%)
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
5/12
Typical Performance Characteristics (Continued)
AP1512 Efficiency v.s. Temperature
(Vin=12V,Vout=5V,Io=2A)
0
10
20
30
40
50
60
70
80
90
100
-50 -30 -10 10 30 50 70 90 110 130 150
Temperature (TA) (°C)
Efficiency (%)
AP1512 Efficiency v.s. Temperature
(Vin=12V,Vout=3.3V,Io=2A)
0
10
20
30
40
50
60
70
80
90
100
-50 -30 -10 10 30 50 70 90 110 130 150
Tem
p
erature
(
TA
)
(
°C
)
Efficiency (%)
AP1512 Supply Current v.s. Temperature
(Vcc=12V , No Load ,Von/off =0V(Switch ON) ,Von/off =5V(Switch OFF))
0
1
2
3
4
5
6
7
8
-40 -25 -10 5 20 35 50 65 80 95 110 125
Supply Current (mA)
Temperature (TA) (°C)
Switch ON
0
10
20
30
40
50
60
70
80
90
100
-40 -25 -10 5 20 35 50 65 80 95 110 125
Supply Current (uA)
Temperature (TA) (°C)
Switch OFF
AP1512 Output Voltage v.s. Temperature
(Vin=12V, Vout=5V, Io=1A)
4.70
4.75
4.80
4.85
4.90
4.95
5.00
5.05
5.10
-50 0 50 100 150
Output Voltage (V)
Temperature (TA) (°C)
AP1512 Threshold Voltage v.s. Temperature
(Vcc=12V, Vout=5V)
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
-50 0 50 100 150
Threshold Voltage (V)
Temperature (TA) (°C)
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
6/12
Typical Performance Characteristics (Continued)
AP1512 Frequency v.s. Temperature
(Vcc=12V, Io=1A, Vout=5V)
40
45
50
55
60
-50 -30 -10 10 30 50 70 90 110 130 150
Temperature (TA) (°C)
Frequency (KHz)
AP1512 Current Limit v.s. Temperature
(Vcc=60V, Vout=5V)
2.8
3
3.2
3.4
3.6
-50 0 50 100 150
Current Limit (A)
Temperature (TA) (°
AP1512 Quiescent Current v.s. Supply Voltage
(force driver off)
5.2
5.4
5.6
5.8
6
6.2
0 1224364860
Quiescent Current (A)
Supply Voltage(V)
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
7/12
Typical Application Circuit
(1) Adjustable Type Circuit
A. Vin=10V~60V, Vout=5V; Iout=0.3A~2A, Iout below 0.3A DCM
C5
1n
L1
47uH
12
R2
3K
Vin
C2
1u
D1
SR360
ON/OFF
R3
1K
C1
100uF/100V
Vout
AP1512/A
1
5
2
4
3
Vin
SD
OUTPUT
FB
GND
0.1u
C3
470uF/16V
C7
B. Vin=10V~60V, Vout=3.3V, Iout=0.3A~2A, Iout below 0.3A DCM
C5
1n
L1
47uH
12
R2
2K
Vin
C2
1u
D1
SR360
ON/OFF
R3
1.2K
C1
100uF/100V
Vout
AP1512/A
1
5
2
4
3
Vin
SD
OUTPUT
FB
GND
0.1u
C3
470uF/16V
C7
(2) Fixed Type Circuit
A. Vin=10V~60V, Vout=5V, Iout=0.7A~2A, Iout below 0.7A DCM
L1
47uH
12
Vin
C2
1u
D1
SR360
ON/OFF
C1
100uF/100V
Vout
AP1512/A
1
5
2
4
3
Vin
SD
OUTPUT
FB
GND
10n
C3
470uF/16V
C7
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
8/12
Typical Application Circuit (Continued)
B. Vin=10V~60V, Vout=3.3V, Iout=0.7A~2A, Iout below 0.7A DCM
L1
33uH
12
Vin
C2
3.3u
D1
SR360
ON/OFF
C1
220uF/100V
Vout
AP1512/A
1
5
2
4
3
Vin
SD
OUTPUT
FB
GND
3.3u
C3
1500uF/16V
C7
Function Description
+V
IN
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 (+V
IN
– V
SAT
) and approximately – 0.5V,
with a duty cycle of approximately V
OUT
/ V
IN
. 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 two packages, a 5-pin
TO-220 and a 5-pin surface mount TO-263.
The TO-220 package needs a heat sink under most
conditions. The size of the heatsink depends on the
input voltage, the output voltage, the load current
and the ambient temperature. The AP1512/A
junction temperature rises above ambient
temperature for a 2A load and different input and
output voltages. The data for these curves was
taken with the AP1512/A (TO-220 package)
operating as a buck
switching regulator in an ambient temperature of
25
o
C (still air). These temperature rise numbers are
all approximate and there are many factors that can
affect these temperatures. Higher ambient
temperatures require more heat sinking.
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 copper area that the
package is soldered to should be at least 0.4 in
2
,
and ideally should have 2 or more square inches of
2 oz. Additional copper area improves the thermal
characteristics, but with copper areas greater than
approximately 6 in
2
, only small improvements in
heat dissipation are realized. If further thermal
improvements are needed, double sided, multilayer
PC board with large copper areas and/or airflow are
recommended.
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
9/12
Function Description (Continued)
The AP1512/A (TO-263 package) junction
temperature rise 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.
Marking Information
(1) TO263-5L
1512X-XX
Blank: ADJ
Logo
ID code
Year:
( Top View )
"02" = 2002
"01" = 2001
YY WW X
Xth week: 01~52
~
Part Number:
-Output Type:
-33: 3.3V
-50: 5.0V
-12: 1.2V
Blank: AP1512
A: AP1512A
(2) TO220-5L
1512X- XX
ID code
Year:
( Top View )
"02" = 2002
"01" = 2001
YY
WW
X
Xth week: 01~52
~
Blank: ADJ
Logo
Part Number:
-Output Type:
-33: 3.3V
-50: 5.0V
-12: 1.2V
Blank: AP1512
A: AP1512A
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
10/12
Package Information
(1) Package Type: TO220-5L
D
Q
E
b
e1
A
J1
F
C
ΦP
H1
L
e
Dimensions In Millimeters Dimensions In Inches
Symbol Min. Nom. Max. Min. Nom. Max.
A 4.07
4.45 4.82 0.160 0.175 0.190
b 0.76 0.89 1.02 0.030 0.035 0.040
C 0.36 0.50 0.64 0.014
0.020 0.025
D 14.22 14.86 15.50 0.560 0.585 0.610
E 9.78 10.16 10.54 0.385 0.400 0.415
e 1.57 1.71 1.85 0.062 0.067 0.073
e1 6.68 6.81 6.93 0.263 0.268 0.273
F 1.14 1.27 1.40 0.045 0.050 0.055
H1 5.46 6.16 6.86 0.215 0.243 0.270
J1 2.29 2.74 3.18 0.090 0.108 0.125
L 13.21 13.97 14.73 0.520 0.550 0.580
Øp 3.68 3.81 3.94 0.145 0.150 0.155
Q 2.54 2.73 2.92 0.100 0.107 0.115
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
11/12
Package Information (Continued)
(2) Package Type: TO263-5L
E
L2
eB
D
L
A
C2
C
L1
1.0
2.5
15.7
10.9
9.1
1.7
Land Pattern Recommendation (Unit: mm)
Dimensions In Millimeters Dimensions In Inches
Symbol Min. Nom. Max. Min. Nom. Max.
A 4.07 4.46 4.85 0.160 0.176 0.191
B 0.66 0.84 1.02 0.026 0.033 0.040
C 0.36 0.50 0.64 0.014 0.020 0.025
C2 1.14 1.27 1.40 0.045 0.050 0.055
D 8.65 9.15 9.65 0.341 0.360 0.380
E 9.78 10.16 10.54 0.385 0.400 0.415
e 1.57 1.71 1.85
0.062 0.068 0.073
L 14.61 15.24 15.88 0.575 0.600 0.625
L1 2.29 2.54 2.79 0.090 0.100 0.110
L2 - - 2.92 - - 0.115
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
AP1512/A
50KHz, 2A/3A PWM Buck DC/DC Converter
Anachip Corp.
www.anachip.com.tw Rev.1.1 Oct. 14, 2005
12/12
Package Information (Continued)
(3) Package Type: TO220-5L(R) Mechanical drawing
E
Q
D
b
A
F
H1
d1
d2
J3
J1
J2
e
H2
H3
A
J1
J2
J3
E
Dimensions In Millimeters Dimensions In Inches
Symbol Min. Nom. Max. Min. Nom. Max.
A 4.4 4.6 4.7 0.175
0.180 0.185
b 0.7 0.8 0.9 0.027 0.032 0.037
D 8.4 8.7 8.9 0.330 0.340 0.350
d1 1.0 0.039
d2 6.3 0.248
E 9.91 10.16 10.41 0.390 0.400 0.410
e 1.6 1.7 1.8 0.062 0.067 0.072
F 1.2 1.25 1.3 0.048 0.050 0.052
H1 6.4 0.250
H2 20.8 21.6 22.4 0.820 0.850 0.880
H3 23.9 24.7 25.5 0.942 0.972 1.002
J1 2.7 0.105
J2 3.7 4.5 5.3 0.147 0.177 0.207
J3 8.4 0.331
Q 2.5 2.8 3.0 0.100 0.110 0.120
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1512/A
See Diodes Datasheet for TO263-5L package
