DIODES AP2004_09

AP2004
PWM BUCK CONTROLLER
General Description
Features
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The AP2004 integrates Pulse-Width-Modulation (PWM) control
circuit into a single chip, mainly designs for power-supply
regulator. All the functions include an on-chip 1.25V reference
output, an error amplifier, an adjustable oscillator, a soft-start,
UVLO, SCP circuitry, and a push-pull output circuit. Switching
frequency is adjustable by trimming CT. During low VCC situation,
the UVLO makes sure that the outputs are off until the internal
circuit operates normally.
PWM Buck Control Circuitry
Operating voltage can be up to 27V
Under voltage Lockout (UVLO) Protection
Short Circuit Protection (SCP)
Soft-start circuit
Variable Oscillator Frequency -- 300Khz Max
1.25V voltage reference Output
8-pin SOP package
SOP-8L: Available in “Green” Molding Compound
(No Br, Sb)
Lead Free Finish/ RoHS Compliant (Note 1)
Applications
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Backlight inverter
LCD Monitor
CDROM, XDSL Product
DC/DC converters in computers, etc.
Ordering Information
AP 2004 S X - 13
Device
Lead-free
AP2004SL-13
AP2004SG-13
Notes:
Package
Lead Free
Packing
S : SOP-8L
L : Lead Free
G : Green
13 : Tape & Reel
Package
Code
S
S
Packaging
(Note 2)
SOP-8L
SOP-8L
13” Tape and Reel
Quantity
Part Number Suffix
2500/Tape & Reel
-13
2500/Tape & Reel
-13
1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied. Please visit our website at
http://www.diodes.com/products/lead_free.html.
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.
AP2004 Rev. 3
1 of 8
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FEBRUARY 2009
© Diodes Incorporated
AP2004
PWM BUCK CONTROLLER
Pin Assignments
( Top View )
OUT
1
8
GND
VCC
2
7
CT
COMP
3
6
SS
4
5
SCP
FB
SOP-8L
Pin Descriptions
Pin Name
Description
CT
Timing Capacitor
FB
Voltage Feedback
SS
Soft-Start.
COMP
Feedback Loop Compensation
OUT
PWM Output
GND
Ground
VCC
Supply Voltage
SCP
Short Circuit Protection
AP2004 Rev. 3
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© Diodes Incorporated
AP2004
PWM BUCK CONTROLLER
Block Diagram
VCC
1.25V
CT
SS
2.5V
Internal use
Bandgap
Reference
Oscillator
UVLO
VCC
MAX. 300KHz
Iss
PWM Amplifier
FB
+
+
-
OUT
Error Amplifier
COMP
1.5V
0.7V
+
+
SCP
GND
Absolute Maximum Ratings
Symbol
PD
VCC
VI
VO
ISOURCE
ISINK
TOP
TST
Parameter
Power dissipation at 25°C
Supply voltage
Amplifier input voltage
Collector output voltage
Source current
Sink current
Operating junction temperature range
Storage temperature range
Rating
600
28
20
VCC-1.0V
200
200
-20 to +125
-65 to +150
Unit
mW
V
V
V
mA
mA
o
C
o
C
Recommended Operating Conditions
Symbol
Min
Max
Unit
Supply voltage
3.6
27
V
VI
Amplifier input voltage
1.05
1.45
V
VO
Collector output voltage
Vcc-1.5
V
VCC
Parameter
IFB
Current into feedback terminal
RF
Feedback resistor
100
CT
Timing capacitor
100
6800
pF
Oscillator frequency
10
300
KHz
FOSC
AP2004 Rev. 3
3 of 8
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45
µA
kΩ
FEBRUARY 2009
© Diodes Incorporated
AP2004
PWM BUCK CONTROLLER
Electrical Characteristics
(TA = 25ºC, VCC = 6V, f = 200 Khz)
Reference (REF)
Symbol
Parameter
Comp connect to FB
VREF
Output voltage change with
temperature
Under voltage lockout (UVLO)
Symbol
Parameter
VUT
Upper threshold voltage (VCC)
VLWT
Lower threshold voltage (VCC)
VHT
Hysteresis (VCC)
Short-circuit protection (SCP) control
Symbol
Parameter
VIT
Input threshold voltage
VSTB
Standby voltage
VLT
Latched input voltage
ISCP
Input (source) current
Comparator threshold voltage
VCT
(COMP)
Oscillator (OSC)
Symbol
Parameter
FOSC
Frequency
Standard deviation of frequency
ΔFOSC
Frequency change with voltage
Error-amplifier
Symbol
Parameter
VIO
Input offset voltage
IIO
Input offset current
IIB
Input bias current
VCM
AV
GBW
CMRR
VOH
VOL
IOI
IOO
AP2004 Rev. 3
Conditions
Min
1.225
Typ.
1.25
-0.1
-0.2
Max
1.275
±1
±1
Unit
V
%
%
Min
Typ.
2.9
2.4
500
Max
Unit
V
V
mV
Min
0.60
100
Typ.
0.67
130
50
-15
Max
0.75
160
100
-20
Unit
V
mV
mV
µA
TA = -20ºC ~ 25ºC
TA = 25ºC ~ 85ºC
Conditions
IO(REF) = 0.1mA
TA = 25ºC
Conditions
TA = 25ºC
No pull up
No pull up
VI = 0.7V, TA = 25ºC
-10
1.5
Conditions
CT = 270 pF
CT = 270 pF
VCC = 3.6V ~ 20V
Min
Conditions
VO (FB) = 1.25V
VO (FB) = 1.25V
VO (FB) = 1.25V
Min
Common-mode input voltage range
VCC = 3.6V ~ 20V
1.05
Open-loop voltage amplification
Unity-gain bandwidth
Common-mode rejection ratio
Max. output voltage
Min. output voltage
Output (sink) current (COMP)
Output (source) current (COMP)
RF = 200 kΩ
Typ.
200
10
1
Max
Typ.
Max
±6
±100
500
Unit
mV
nA
nA
1.45
V
160
70
60
Vref-0.1
V
%
80
1.5
80
1
VID = -0.1V, VO = 1.25V
VID = 0.1V, VO = 1.25V
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0.5
-45
1.6
-70
Unit
KHz
dB
MHz
dB
V
V
mA
µA
FEBRUARY 2009
© Diodes Incorporated
AP2004
PWM BUCK CONTROLLER
Electrical Characteristics
Output section
Symbol
ILEAK
IDRV
VSAT
(Continued) (TA = 25ºC, VCC = 6V, f = 200 Khz)
Parameter
Conditions
VT100
Total device
Symbol
ICCA
Soft Start
Symbol
Typ.
Max
Unit
10
µA
Leakage current
VO = 25V
Sink current
VIN = 20V
200
mA
Source current
VIN = 20V
200
mA
Output saturation voltage
IO = 10 mA
1.0
VO = 6V
120
ISC
Short-circuit output current
PWM comparator
Symbol
Parameter
VT0
Min
Conditions
Min
Input threshold voltage at f = 10 KHz CT
(COMP)
Maximum duty cycle
Parameter
Conditions
Average supply current
Conditions
V
mA
Typ.
Max
Unit
0.6
0.7
V
1.2
1.3
Min
Typ.
Max
Unit
6
10
mA
Typ.
Max
Unit
CT = 270pF
Parameter
1.5
Min
V
VSS
Soft-start Voltage
2.3
V
ISS
Constant Charge Current
20
µA
Typical Application Circuit
R3 1K~30K
Vcc = 12V
C2
10nF
Optional
Q1
1 OUT
8
GND
2 VCC
CT 7
3 COMP SS 6
FB
SCP 5
4
P mos
AF9435P
AF4835P
5A
C1
470uF
L1
22uH
R1
9K
Output
5V/5A
C4
50nF
Optional
C3
470uF
R2
3K
C4 270pF
C5 50nF
C6 220nF
⎛
⎝
Vout=Vref ⎜1 +
R1 ⎞
⎟
R2 ⎠
Step-Down DC/DC converter
AP2004 Rev. 3
5 of 8
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© Diodes Incorporated
AP2004
PWM BUCK CONTROLLER
Typical Characteristics
REFERENCE OUTPUT VOLTAGE
vs.
POWER-SUPPLY VOLTAGE
AVERAGE SUPPLY CURRENT
vs.
POWER-SUPPLY VOLTAGE
5
Icc-Average
Supply Current
(mA)
VrefReference
Output Voltage
(V)
1.26
1.255
1.25
1.245
1.24
1.235
1.23
1.225
1.22
4
8
12
16
20
24
4
3
2
1
0
28
0
4
Vcc-Power Supply Voltage (V)
AVERAGE SUPPLY CURRENT
vs.
AMBIENT TEMPERATURE
VCT (V)
ICC - Average
Supply Current
(mA)
6
5
4
3
2
-25
0
25
50
75
0
100
tscp-SCP Time-out
Period (ms)
fosc - Frequency
(KHz)
300
250
200
150
100
50
28
VCT(min)
VCT(max)
100
200
300
30
25
20
15
10
5
1100 1600 2100 2600 3100 3600 4100 4600 5100 5600 6100 6600
0
45
90 135 180 225 270 315 360 405 450 495
Cscp - SCP Capacitance (nF)
CT-Timing Capacitor (pF)
AP2004 Rev. 3
24
SCP TIME-OUT PERIOD
vs.
SCP CAPACITANCE
35
0
600
20
Frequency (KHz)
OSCILLATOR FREQUENCY
vs.
TIMING CAPACITANCE
100
16
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
TA - Ambient Temperatrure(℃)
350
12
VCT vs. Frequency
7
-50
8
Vcc - Power-Supply Voltgae (V)
6 of 8
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© Diodes Incorporated
AP2004
PWM BUCK CONTROLLER
Typical Characteristics (Continued)
SOFT-START TIME (Ts)
vs.
SOFT-START CAPACITOR (Css)
30
Ts (mS)
25
20
15
10
5
0
25
50
75
100
125
150
175
200
Css (nF)
Marking Information
(1) SOP-8L
( Top View )
8
5
Logo
Part Number
AP2004
YY WW X X
1
AP2004 Rev. 3
4
L : Lead Free
G : Green
YY : Year : 08, 09,10~
WW : Week : 01~52; 52
represents 52 and 53 week
X : Internal Code
7 of 8
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© Diodes Incorporated
AP2004
PWM BUCK CONTROLLER
Package Information
(All Dimensions in mm)
0.254
0.10/0.20
3.85/3.95
5.90/6.10
(1) Package Type: SOP- 8L
Gauge Plane
Seating Plane
0.62/0.82
Detail "A"
7°~9°
0.15/0.25
1.30/1.50
1.75max.
0.35max. 45°
7°~9°
Detail "A"
0°/8°
0.3/0.5
1.27typ
4.85/4.95
5.4
8x-0.60
8x-1.55
6x-1.27
Land Pattern Recommendation
(Unit: mm)
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.
AP2004 Rev. 3
8 of 8
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© Diodes Incorporated