ANACHIP AP1510

AP1510
PWM Control 3A Step-Down Converter
„ Features
„ General Description
- Input voltage: 3.6V to 23V.
- 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.
AP1510 consists of step-down switching regulator
with PWM control. These devices include a reference
voltage source, oscillation circuit, error amplifier,
internal PMOS and etc.
AP1510 provides low-ripple power, high efficiency,
and excellent transient characteristics. The PWM
control circuit is able to very 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 of up to 23V, it is also
ideal when operating via an AC adapter.
„ Pin Descriptions
„ Pin Assignments
Name
FB
8
Vss
7
Vss
OCSET 3
6
Output
VCC 4
5
FB 1
EN 2
EN
AP1510
OCSET
VCC
Output
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. 1.1 Jan 25, 2005
1/7
AP1510
PWM Control 3A Step-Down Converter
„ Ordering Information
AP 1510 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
VON/OFF
EN
100uA
Vss
OCSET
„ Absolute Maximum Ratings
Symbol
*1
VCC
VFB
Parameter
VCC Pin Voltage
Feedback Pin Voltage
Rating
Unit
VSS - 0.3 to VSS + 25
V
VSS - 0.3 to VCC
V
VON/OFF*1
ON/OFF Pin Voltage
VSS - 0.3 to VIN + 0.3
V
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. 1.1
2/7
Jan 25, 2005
AP1510
PWM Control 3A Step-Down Converter
„ Electrical Characteristics (VIN = 12V, Ta=25°C, unless otherwise specified)
Symbol
Parameter
VFB Feedback Voltage
VIN
Input Voltage
ISW Switch Current
Current Consumption
ISSS
During Power Off
∆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
ISH
EN Pin Input Leakage
Current
ISL
IOCSET OCSET Pin Bias Current
TSS
Soft-Start Time
RDSON Internal MOSFET Rdson
EFFI
Efficiency
Conditions
Min.
0.784
3.6
3.5
Typ.
0.8
-
Max.
0.816
23
-
Unit
V
V
A
VON/OFF =0V
-
10
-
µA
VIN = 5V~23V, IOUT=0.2A
-
1
2
%
IOUT = 0.1 to 3A
-
0.2
0.5
%
Measure waveform at SW pin
240
300
360
KHz
Measure waveform at SW pin
10
30
60
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 = 3A
2.0
75
0.3
-
20
-10
90
2
110
70
0.8
105
5
150
100
-
91
-
IOUT=0.1A
---
V
µA
µA
µA
ms
mΩ
%
„ Typical Application Circuit
VIN
Vcc
VOUT
Output
ROCSET COCSET
Option
CC
Optional
RA
FB
OCSET
CIN
CVcc
RB
AP1510
+
-
D1
COUT
REN
100K
EN
VSS
CEN
0.1µ
Note: VOUT = VFB x (1+RA/RB)
RB=0.7K~5K ohm
Anachip Corp.
www.anachip.com.tw
Rev. 1.1
3/7
Jan 25, 2005
AP1510
PWM Control 3A Step-Down Converter
AP1510 Vin v.s. Frequency
(Vout=3.3V; Iout=0.2A)
350
345
340
335
330
325
320
315
310
305
300
FB (V)
Fosc (KHz)
„ Typical Performance Characteristics
0
5
10
15
20
Vin (V)
0
3.35
Vout (A)
Vout(V)
3.30
3.25
3.20
3.15
3.10
0
5
10
Vin(V)
15
20
0.84
0.83
0.82
0.81
0.80
0.79
0.78
0.77
0.76
0.75
0.74
25
AP1510 Line Regulation
(Vout=3.3V; Iout=0.2A)
3.40
25
AP1510 Vin v.s. FB
(Vout=3.3V; Iout=0.2A)
5
10
15
20
Vin (V)
25
AP1510 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
1.0
2.0
3.0
4.0
Iout (A)
AP1510 Efficiency
Efficiency (%)
100
90
80
70
60
50
40
30
20
Vout:5.0V
Vout:3.3V
10
0
0.0
1.0
Iout (A)
2.0
3.0
Anachip Corp.
www.anachip.com.tw
Rev. 1.1
4/7
Jan 25, 2005
AP1510
PWM Control 3A Step-Down Converter
„ Typical Performance Characteristics (Continued)
AP1510 Vout Ripple
(Vin=12V; Vout=3.3V; Iout=0.1A)
AP1510 Vout Ripple
(Vin=12V; Vout=3.3V; Iout=3A)
„ 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. 1.1
5/7
Jan 25, 2005
AP1510
PWM Control 3A Step-Down Converter
„ Function Description
RDS(ON) Current Limiting
The current limit threshold is setting by connecting
an external resistor from VCC supply to OCSET.
The voltage drop across this resistor is due to the
100uA internal sink sets the voltage at the pin.
When the PWM voltage is less than the voltage at
OCSET, an over-current condition occurs.
PWM Control
The AP1510 consists of DC/DC converters that
employ a pulse-width modulation (PWM) system.
In converters of the AP1510, the pulse width varies
in a range from 0 to 100, according to the load
current, and yet 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.
Under Voltage Lockout
The under voltage lockout circuit of the AP1510
assures that the high-side MOSFET driver outputs
remain in the off state whenever the supply voltage
drops below set parameters. Lockout occurs if VCC
falls below 3.3V. Normal operation resumes once
VCC rises above 3.5V.
„ Marking Information
( Top View )
8
5
Logo
AP1510
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. 1.1
6/7
Jan 25, 2005
AP1510
PWM Control 3A 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
0O
8O
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. 1.1
7/7
Jan 25, 2005