ANACHIP AP1513

AP1513
PWM Control 2A Step-Down Converter
„ Features
„ General Description
- Input voltage: 3.6V to 18V.
- Output voltage: 0.8V to VCC.
- Duty ratio: 0% to 100% PWM control
- Oscillation frequency: 300KHz typ.
- Soft-start, Current limit, Enable function
- Thermal Shutdown function
- Built-in internal SW P-channel MOS
- SOP-8L Pb-Free Package.
AP1513 consists of step-down switching regulator
with PWM control. These devices include a reference
voltage source, oscillation circuit, error amplifier,
internal PMOS and etc.
AP1513 provides low-ripple power, high efficiency,
and excellent transient characteristics. The PWM
control circuit is able to vary the duty ratio linearly
from 0 up to 100%. This converter also contains an
error amplifier circuit as well as a soft-start circuit that
prevents overshoot at startup. An enable function,
an over current protect function and a short circuit
protect function are built inside, and when OCP or
SCP happens, the operation frequency will be
reduced from 300KHz to 30KHz. Also, an internal
compensation block is built in to minimum external
component count.
„ Applications
- PC Motherboard
- LCD Monitor
- Graphic Card
- DVD-Video Player
- Telecom Equipment
- ADSL Modem
- Printer and other Peripheral Equipment
- Microprocessor core supply
- Networking power supply
With the addition of an internal P-channel Power MOS,
a coil, capacitors, and a diode connected externally,
these ICs can function as step-down switching
regulators. They serve as ideal power supply units for
portable devices when coupled with the SOP–8L
mini-package, providing such outstanding features as
low current consumption. Since this converter can
accommodate an input voltage up to 18V, it is also
suitable for the operation via an AC adapter.
„ Pin Descriptions
„ Pin Assignments
Name
FB
8
Vss
7
Vss
OCSET 3
6
Output
VCC 4
5
Output
FB 1
EN 2
EN
AP1513
OCSET
VCC
Output
VSS
Pin
Description
1 Feedback pin.
Power-off pin
H: Normal operation
(Step-down operation)
2
L: Step-down operation
stopped
(All circuits deactivated)
Add an external resistor to set
3
max output current.
4 IC power supply pin
Switch Pin. Connect external
inductor/diode here. Minimize
5、6
trace area at this pin to reduce
EMI.
7、8 GND Pin
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. 1.3 Nov 17, 2005
1/7
AP1513
PWM Control 2A Step-Down Converter
„ Ordering Information
AP 1513 X X
Packing
Package
S: SOP-8L
Blank : Tube
A : Taping
„ Block Diagram
Output
Oscillation
Circuit
Reference Voltage
Source with Soft Start
Vcc
+
PWM-Switched
Control Circuit
FB
-
Thermal
Shutdown
VEN
EN
100uA
Vss
OCSET
„ Absolute Maximum Ratings
Symbol
Parameter
Rating
Unit
VSS - 0.3 to VSS + 20
V
VSS - 0.3 to VCC
V
V
VCC
VCC Pin Voltage
VFB
Feedback Pin Voltage
VEN
EN Pin Voltage
VSS - 0.3 to VIN + 0.3
VOUTPUT
Switch Pin Voltage
VSS - 0.3 to VIN + 0.3
V
PD
Power Dissipation
Internally limited
mW
TOPR
Operating Temperature Range
o
-20 to +125
C
o
TSTG
Storage Temperature Range
-40 to +150
C
Caution: The absolute maximum ratings are rated values exceeding which the product could suffer physical
damage. These values must therefore not be exceeded under any conditions.
Anachip Corp.
www.anachip.com.tw
Rev. 1.3
2/7
Nov 17, 2005
AP1513
PWM Control 2A Step-Down Converter
„ Electrical Characteristics (VIN = 12V, Ta=25°C, unless otherwise specified)
Symbol
VIN
VFB
IFB
ISW
ISSS
Parameter
Input Voltage
Feedback Voltage
Feedback Bias Current
Switch Current
Current Consumption
During Power Off
Conditions
∆VOUT
Line Regulation
/VOUT
∆VOUT
Load Regulation
/VOUT
fOSC Oscillation Frequency
Frequency of Current Limit
fOSC1
or Short Circuit Protect
VSH
EN Pin Input Voltage
VSL
EN Pin Input Leakage
ISH
Current
ISL
IOCSET OCSET Pin Bias Current
TSS
Soft-Start Time
RDSON Internal MOSFET Rdson
EFFI
θJA
Min.
3.6
0.784
2.5
Typ.
0.8
0.1
-
Max.
18
0.816
0.5
-
Unit
V
V
µA
A
VEN =0V
-
10
-
µA
VIN=5V~18V
-
1
2
%
IOUT=0.1 to 2A
-
0.2
0.5
%
Measure waveform at SW pin
240
300
400
KHz
Measure waveform at SW pin
10
-
-
KHz
Evaluate oscillation at SW pin
Evaluate oscillation stop at SW pin
----VIN=5V, VFB=0V
VIN=12V, VFB=0V
VIN=12V, VOUT = 5V
IOUT=2A
2.0
75
0.3
-
20
-10
90
2
110
70
0.8
105
5
150
100
-
92
-
-
65
-
-IOUT=0.1A
IOUT=0.1A
--
Efficiency
Thermal Resistance
Junction-to-Ambient
V
µA
µA
µA
ms
mΩ
%
o
C/W
„ Typical Application Circuit
Output
ROCSET COCSET
3K
Option
CIN
CVcc
0.1uF
REN
100K
EN
33uH
CC
Optional
AP1513
RA
6.8K
+
FB
OCSET
470uF
VOUT=5V/2A
L1
Vcc
VIN
VSS
D1
C
+
0.1uF
-
COUT
470uF
RB
1.3K
CEN
0.1uF
Note: VOUT = VFB x (1+RA/RB)
RB=0.7K~5K ohm
VOUT
L1 Value
VIN=12V, IMAX=2A
2.5V
3.3V
22uH
27uH
Anachip Corp.
www.anachip.com.tw
5V
33uH
Rev. 1.3
3/7
Nov 17, 2005
AP1513
PWM Control 2A Step-Down Converter
„ Typical Performance Characteristics
AP1513 Vin v.s. Frequency
(Vout=3.3V; Iout=0.2A)
350
345
335
FB (V)
Fosc (KHz)
340
330
325
320
315
310
0
2
4
6
8
10 12
Vin (V)
14
16
18
0
3.30
Vout (V)
Vout (V)
3.35
3.25
3.20
3.15
3.10
0
2
4
6
8
0.84
0.83
0.82
0.81
0.80
0.79
0.78
0.77
0.76
0.75
0.74
20
AP1513 Line Regulation
(Vout=3.3V; Iout=0.2A)
3.40
10 12 14 16 18 20
Vin (V)
AP1513 Vin v.s. FB
(Vout=3.3V; Iout=0.2A)
2
4
6
8
10
12 14
16 18
Vin (V)
20
AP1513 Load Regulation
(Vin=12V)
5.10
5.09
5.08
5.07
5.06
5.05
5.04
5.03
5.02
5.01
5.00
0.0
0.5
1.0
1.5
Iout (A)
2.0
2.5
AP1513 Efficiency
100
90
Efficiency (%)
80
70
60
50
40
30
Vout:5.0V
20
Vout:3.3V
10
0
0.0
0.5
1.0
1.5
2.0
Iout (A)
Anachip Corp.
www.anachip.com.tw
Rev. 1.3
4/7
Nov 17, 2005
AP1513
PWM Control 2A Step-Down Converter
„ Typical Performance Characteristics (Continued)
AP1513 Vout Ripple
(Vin=12V; Vout=3.3V; Iout=0.1A)
AP1513 Vout Ripple
(Vin=12V; Vout=3.3V; Iout=2A)
„ Test Circuit
VCC
OUTPUT
FB
Oscillation
open
open
OCSET
A
EN
VCC
+
-
A
+
-
VSS
OUTPUT
VCC
OUTPUT
OCSET
EN
FB
VSS
FB
OCSET
EN
VSS
V
+
-
Anachip Corp.
www.anachip.com.tw
Rev. 1.3
5/7
Nov 17, 2005
AP1513
PWM Control 2A Step-Down Converter
„ Function Description
RDS(ON) Current Limiting
The current limit threshold is setting by the external
resistor connecting from VCC supply to OCSET. The
internal 100uA sink current crossing the resistor
sets the voltage at the pin of OCSET. When the
PWM voltage is less than the voltage at OCSET, an
over-current condition is triggered.
PWM Control
The AP1513 consists of DC/DC converters that
employ a pulse-width modulation (PWM) system.
In converters of the AP1513, the pulse width varies
in a range from 0 to 100%, according to the load
current. The ripple voltage produced by the
switching can easily be removed through a filter
because the switching frequency remains constant.
Therefore, these converters provide a low-ripple
power over broad ranges of input voltage and load
current.
ILOAD × RDS(ON) = IOCSET × ROCSET
See above formula for setting the current limit
value.
Under Voltage Lockout
The under voltage lockout circuit of the AP1513
assures that the high-side MOSFET driver outputs
remain in the off state whenever the supply voltage
drops below 3.3V. Normal operation resumes once
VCC rises above 3.5V.
„ Marking Information
( Top View )
8
5
Logo
AP1513
Part no.
YY WW X
4
Anachip Corp.
www.anachip.com.tw
~
1
ID code: internal
Xth week: 01~52
Year: "01" =2001
"02" =2002
Rev. 1.3
6/7
Nov 17, 2005
AP1513
PWM Control 2A Step-Down Converter
„ Package Information
H
E
Package Type: SOP-8L
L
VIEW "A"
D
0.015x45
7 (4X)
e
B
A1
C
A
A2
7 (4X)
VIEW "A"
y
Symbol
A
A1
A2
B
C
D
E
e
H
L
y
θ
Dimensions In Millimeters
Min.
Nom.
Max.
1.40
1.60
1.75
0.10
0.25
1.30
1.45
1.50
0.33
0.41
0.51
0.19
0.20
0.25
4.80
5.05
5.30
3.70
3.90
4.10
1.27
5.79
5.99
6.20
0.38
0.71
1.27
0.10
8O
0O
Anachip Corp.
www.anachip.com.tw
Dimensions In Inches
Min.
Nom.
Max.
0.055
0.063
0.069
0.040
0.100
0.051
0.057
0.059
0.013
0.016
0.020
0.0075
0.008
0.010
0.189
0.199
0.209
0.146
0.154
0.161
0.050
0.228
0.236
0.244
0.015
0.028
0.050
0.004
0O
8O
Rev. 1.3
7/7
Nov 17, 2005