ANACHIP AP1509

AP1509
150KHz, 2A PWM Buck DC/DC Converter
Features
General Description
- Output voltage: 3.3V, 5V, 12V and adjustable
output version
- Adjustable version output voltage range, 1.23V to
18V+4%
- 150KHz +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 22V
- Output load current: 2A
- SOP-8L packages
- Low power standby mode
- Built-in switching transistor on chip
The AP1509 series are monolithic IC designed for a
step-down DC/DC converter, and own the ability of
driving a 2A 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. If current
limit function occurred and VFB is down to 0.5V
below, the switching frequency will be reduced.
The AP1509 series operates at a switching
frequency of 150KHz 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 8-lead SOP-8 package.
Applications
- Simple High-efficiency step-down regulator
- On-card switching regulators
- Positive to negative converter
Pin Assignments
Pin Descriptions
Name
(Top View)
VIN
Output
FB
SD
1
2
3
4
8
7
6
5
VIN
GND
GND
GND
GND
Output
GND
SOP-8L
Description
Operating voltage input
Switching output
Ground
FB
Output voltage feedback control
SD
ON/OFF Shutdown
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. 0.1 Nov 27, 2003
1/8
AP1509
150KHz, 2A PWM Buck DC/DC Converter
Ordering Information
AP1509 XX X X X
Output version
Package
Blank : Adjustable
-33 : 3.3V
-50 : 5.0V
-12 : 12V
S: SOP-8L
Lead Free
Packing
Blank : Tube
Blank : Normal
L : Lead Free Package A : Taping
Block Diagram
SD
VIN
200mV
Current
Source
bias
1.235V
Reference
2.5V
Regulator
220mV
Start
up
+
Comp
_
_
Comp
+
Frequecy
compensation
_
FB
+
Amp
_
Comp
+
Pre-driver
2A
Switch
Output
150kHz
OSC.
Thermal
Limit
Gnd
Anachip Corp.
www.anachip.com.tw
Rev.0.1 Nov 27, 2003
2/8
AP1509
150KHz, 2A PWM Buck DC/DC Converter
Absolute Maximum Ratings
Symbol
Parameter
Rating
Unit
+24
V
ON/OFF Pin input voltage
-0.3 to +18
V
VFB
Feedback Pin voltage
-0.3 to +18
V
VOUT
Output voltage to Ground
VCC
Supply Voltage
VSD
PD
Power dissipation
TST
Storage temperature
-1
V
Internally limited
W
-65 to +150
o
C
o
C
TOP
Operating temperature
-40 to +125
VOP
Operating voltage
+4.5 to +22
V
Electrical Characteristics (All Output Voltage Versions)
Unless otherwise specified, VIN=12V for 3.3V, 5V, adjustable version and VIN=18V for the 12V version. ILOAD = 0.5A
Symbol
IB
Parameter
Feedback bias current
FOSC
Oscillator frequency
FSCP
Oscillator frequency
short circuit protect
VSAT
DC
ICL
IL
IQ
ISTBY
VIL
VIH
IH
IL
ΘJC
ΘJA
Conditions
VFB=1.3V
(Adjustable version only)
of When current limit occurred
and VFB < 0.5V, Ta=25 oC
IOUT=2A
Saturation voltage
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
No outside circuit
VFB=0V force driver on
Output
No outside circuit
Output = 0
leakage
VFB=12V force driver off
Output = -1 current
VIN=22V
Quiescent Current
VFB=12V force driver off
Standby Quiescent
ON/OFF pin=5V
Current
VIN=22V
Low (regulator ON)
ON/OFF pin logic input
threshold voltage
High (regulator OFF)
ON/OFF pin logic input
VLOGIC=2.5V (OFF)
current
ON/OFF pin input current VLOGIC=0.5V (ON)
Junction to
Thermal Resistance
SOP-8L
case
Thermal Resistance
Junction to
SOP-8L
With copper area of
ambient
2
approximately 3 in
Min.
Typ.
-10
127
110
150
5
15
Max.
-50
-100
173
173
Unit
25
KHz
nA
KHz
1.4
1.25
V
1.5
100
0
%
3
A
-200
-5
5
70
2.0
1.3
uA
mA
mA
10
150
200
0.6
uA
V
-0.01
-0.1
uA
-1
15
o
70
o
C/W
C/W
Anachip Corp.
www.anachip.com.tw
Rev.0.1 Nov 27, 2003
3/8
AP1509
150KHz, 2A PWM Buck DC/DC Converter
Electrical Characteristics (Continued)
Symbol
AP1509-ADJ
AP1509-3.3V
Parameter
Limit
Unit
1.23
1.193/1.18
1.267/1.28
V
VMIN
VMAX
Output
Feedback
4.5V < VIN < 22V
0.2A < ILOAD < 2A
VOUT programmed for
3V
η
Efficiency
VIN = 12V, ILOAD=2A
76
Output voltage
4.75V < VIN < 22V
0.2A < ILOAD < 2A
3.3
Efficiency
VIN = 12V, ILOAD=2A
78
Output voltage
7V < VIN < 22V
0.2A < ILOAD < 2A
5
Efficiency
VIN = 12V, ILOAD=2A
83
Output voltage
15V < VIN < 22V
0.2A < ILOAD < 2A
12
Efficiency
VIN = 15V, ILOAD = 2A
90
VOUT
VOUT
η
AP1509-12V
Typ.
VFB
η
AP1509-5V
Conditions
VOUT
η
%
3.168/3.135
3.432/3.465
V
VMIN
VMAX
%
V
VMIN
VMAX
4.8/4.75
5.2/5.25
%
11.52/11.4
12.48/12.6
V
VMIN
VMAX
%
Specifications with boldface type are for full operating temperature range, the other type are for TJ=25ºC.
Typical Application Circuit
FB
12V
3
DC Input
Vin
1
4
Cin
Capacitor
AP1509
-33
5
6
7
2
3.3V/2A
L1
Output
Output Load
Inductor
8
SD Gnd Gnd Gnd Gnd
D1
Schottky Diode
Co
Capacitor
Anachip Corp.
www.anachip.com.tw
Rev.0.1 Nov 27, 2003
4/8
AP1509
150KHz, 2A PWM Buck DC/DC Converter
Typical Performance Characteristics
AP1509 Efficiency v.s. Temperature
(Vin=12V,Vout=5V,Io=2A)
AP1509 Efficiency v.s. Temperature
(Vin=12V,Vout=3.3V,Io=2A)
81
80
79
Efficiency (%)
Efficiency (%)
86
85
84
83
82
81
80
79
78
77
76
75
78
77
76
75
74
73
-50 -30 -10 10 30 50 70 90 110 130 150
-50 -30 -10 10
Temperature (TA) (°C)
30
50
70
90 110 130 150
Temperature (TA) (°C)
AP1509 Saturation Voltage v.s. Temperature
(Vcc=12V,Vfb=0V,VSD=0)
AP1509 Switch Current Limit v.s. Temperature
(Vcc=12V,Vfb=0V)
1.4
Switch Current Limit (A)
5.5
Saturation Voltage (V)
1.3
1.2
2A
1.1
1A
1
0.5A
0.9
0.8
0.7
-50
-25
0
25
50
75
100
5
4.5
4
3.5
3
-50
125
Temperature (TA) (°C)
-30
-10
10
30
50
70
90
Temperature (TA) (°C)
15
14
13
12
11
10
9
8
7
6
5
60
Supply Current (uA)
Supply Current (mA)
AP1509 Supply Current v.s. Temperature
(Vcc=12V , No Load ,Von/off =0V(Switch ON) ,Von/off =5V(Switch OFF))
Switch ON
-50 -30 -10 10
30
50
70
90 110 130 150
55
50
45
Switch OFF
40
35
30
-50 -30 -10 10
30
50
70
90 110 130 150
Temperature (TA) (°C)
Temperature (TA) (°C)
Anachip Corp.
www.anachip.com.tw
Rev.0.1 Nov 27, 2003
5/8
AP1509
150KHz, 2A PWM Buck DC/DC Converter
Typical Performance Characteristics (Continued)
AP1509 Threshold Voltage v.s. Temperature
(Vcc=12V , Io=100mA)
AP1509 ON/OFF Current v.s. ON/OFF Voltage
(Vin=12V)
1.7
10
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
1.5
ON/OFF Current (nA)
Threshold Voltage (V)
1.6
1.4
1.3
1.2
1.1
1
0.9
0.8
-50 -30 -10 10
30
50
70
0
90 110 130 150
Temperature (TA) (°C)
6
9
12
15
18
21
ON/OFF Voltage (V)
AP1509 Feedback Current v.s. Temperature
(Vcc=12V , Vout=5V,Vfb=1.3V)
AP1509 Frequency v.s. Temperature
(Vcc=12V , Io=500mA ,Vout=5V)
170
10
Feedback Current (nA)
165
Frequency (KHz)
3
160
155
150
145
140
0
-10
-20
-30
-40
-50
-50 -30 -10
10
30
50
70
90 110 130 150
-50 -30 -10 10
Temperature (TA) (°C)
30
50
70
90 110 130 150
Temperature (TA) (°C)
Vout (V)
AP1509 Output Voltage v.s. Temperature
(Vin=12V ,Io=2A)
3.5
3.45
3.4
3.35
3.3
3.25
3.2
3.15
3.1
3.05
3
2.95
2.9
-40 -20
0
20
40
60
80 100 120 140 160
Temperature (TA) (°C)
Anachip Corp.
www.anachip.com.tw
Rev.0.1 Nov 27, 2003
6/8
AP1509
150KHz, 2A PWM Buck DC/DC Converter
Function Description
Pin Functions
+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.
Thermal Considerations
The SOP-8 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 AP1509 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
AP1509 (SOP-8 package) operating as a
buck-switching regulator in an ambient temperature
of 25oC (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.
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.
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.
Feedback
Senses the regulated output voltage to complete
the feedback loop.
SD
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
18V) 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.
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, multi-layer 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.
Anachip Corp.
www.anachip.com.tw
Rev.0.1 Nov 27, 2003
7/8
AP1509
150KHz, 2A PWM Buck DC/DC Converter
Marking Information
SOP-8L
(Top view)
Part Number
Output Type:
Blank: Adjustable
33: 3.3V
50: 5.0V
12: 12V
AC
1509-XX
YY WW XX
Logo
Blank: normal
L: Lead Free Package
Date Code
X: Internal code
WW: Nth week
YY: Year
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.0.1 Nov 27, 2003
8/8