AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Features
• • • • • • • • • • • • 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
General Description
The AP1506 series are monolithic IC designed for a step-down DC/DC converter, and own the ability of driving a 3A load without external transistor. 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 to prevent 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 AP1506 series operate 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 5-lead TO-220 or a 5-lead TO-263.
ON /OFF Shutdown Control Input Operating Voltage can be up to 22V Output Load Current: 3A TO220-5L, TO263-5L Packages Low Power standby mode Built-in Switching Transistor On Chip Lead Free Finish/RoHS Compliant (Note 1)
Applications
• • • Simple High-Efficiency Step-Down Regulator On-Card Switching Regulators Positive to Negative Converter
Ordering Information
AP1506 XX X X X Output Version Blank : Adjustable 12 : 12V 33 : 3.3V 50 : 5.0V
Note:
Package
Lead Free
Packing -U : Tube -13 : Taping
L : Lead Free Package T5: TO 220-5L K5: TO 263-5L T5R: TO 220-5L(R)
1. RoHS revision 13.2.2003. Glass and High Temperature Solder Exemptions Applied, see EU Directive Annex Notes 5 and 7.
Device (Note 2)
Lead-free
Package Code
K5 T5 T5R
Packaging
TO263-5L TO220-5L TO220-5L(R)
Quantity
NA 50 50
Tube Part Number Suffix
NA -U -U
13” Tape and Reel Quantity Part Number Suffix
800/Tape & Reel NA NA -13 NA NA
Lead-free
AP1506-XXK5 AP1506-XXT5 AP1506-XXT5R
Lead-free
Note: 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.
AP1506 Rev. 2
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Pin Assignments
( Top View ) 5 SD 4 FB 3 GND 2 Output 1 VIN
Pin Descriptions
Name VIN Output GND FB Description Operating Voltage Input Switching Output Ground Output Voltage Feedback Control
ON /OFF Shutdown
Metal Tab GND
TO263-5L
( Top View ) 5 SD 4 FB 3 GND 2 Output 1 VIN TO220-5L
SD
Block Diagram
SD VIN
200mV Current Source bias 1.235V Reference 2.5V Regulator Start up + Comp Comp + + Amp Frequecy compensation 220mV
FB
Comp +
Pre-driver
3A Switch
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Output
150KHz OSC. Thermal Shutdown
GND
NOVEMBER 2006
© Diodes Incorporated
AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Absolute Maximum Ratings
Symbol VCC VSD VFB VOUT PD TST TOP VOP Parameter Supply Voltage ON/OFF Pin Input Voltage Feedback Pin Voltage Output Voltage to Ground Power Dissipation Storage Temperature Operating Temperature Operating Voltage Rating +24 -0.3 to +18 -0.3 to +18 -1 Internally Limited -65 to +150 -40 to +125 +4.5 to +22 Unit V V V V W
o o
C C
V
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
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 Specifications with boldface type are for full operating temperature range, the other type are for TJ = 25ºC.
Symbol IFB FOSC FSCP VSAT DC ICL IL IQ ISTBY VIL VIH IH IL θJC
Parameter Feedback Bias Current Oscillator Frequency Oscillator Frequency of Short Circuit Protect Saturation Voltage Max. Duty Cycle (ON) Min. Duty Cycle (OFF) Current Limit Output Leakage Output = -1V Current Quiescent Current Standby Quiescent Current Output = 0V
Conditions VFB = 1.3V (Adjustable version only)
Min. 127 110
Typ. -10 150 30 1.4 100 0 4.5 -5 5 70 1.3 -0.1 2.5 3.5 28 23
Max. -50 -100 173 173 50 1.6
Unit nA KHz KHz V % A UA MA MA UA V
When current limit occurred and VFB < 0.5V, Ta = 25 oC IOUT = 3A No outside circuit VFB = 0V force driver on VFB = 0V force driver on VFB = 12V force driver off Peak current No outside circuit VFB = 0 force driver on No outside circuit VFB = 12 force driver off VIN = 22V VFB = 12 force driver off
10 3.6 2.0 -
1.7 5.5 6.5 -200 10 150 200 0.6 -0.01
ON /OFF pin = 5V VIN = 22V ON /OFF Pin Logic Input Low (regulator ON) High (regulator OFF) Threshold Voltage ON /OFF Pin Logic Input Current ON /OFF Pin Input Current
VLOGIC = 2.5V (OFF) VLOGIC = 0.5V (ON) TO220-5L TO263-5L TO220-5L with a copper area of TO263-5L approximately 3in2
UA -1 o o
Thermal Resistance Junction to Case Thermal Resistance Junction to Ambient
C/W
θJA
-
C/W
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Electrical Characteristics (Continued)
Specifications with boldface type are for full operating temperature range, the other type are for TJ = 25ºC.
Symbol
VFB
Parameter Output Feedback Efficiency Output Voltage Efficiency Output Voltage Efficiency Output Voltage Efficiency
AP1506-ADJ
η
VOUT
Conditions 5V < VIN < 22V 0.2A < ILOAD < 3A VOUT programmed for 3V VIN = 12V, ILOAD = 3A 5.5V < VIN < 22V 0.2A < ILOAD < 3A VIN = 12V, ILOAD = 3A 8V < VIN < 22V 0.2A < ILOAD < 3A VIN = 12V, ILOAD = 3A 15V < VIN < 22V 0.2A < ILOAD < 3A VIN = 16V, ILOAD = 3A
VMin. 1.193 1.18 3.168 3.135 4.8 4.75 11.52 11.4 -
Typ. 1.23 74 3.3 75 5 80 12 89
VMax. 1.267 1.28 3.432 3.465 5.2 5.25 12.48 12.6 -
Unit V
% V
AP1506-3.3V
η VOUT
% V % V
AP1506-5V
η VOUT
AP1506-12V
η
%
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Typical Performance Characteristics
AP1506 Efficiency vs. Temperature (Vin = 12V, Vout = 5V, Io = 3A)
83 82 81 80
AP1506 Efficiency vs. Temperature (Vin = 12V, Vout = 3.3V, Io = 3A)
78 77 76
Efficiency (%)
Efficiency (%)
30 50 70 90 110 130 150
79 78 77 76 75 74 73 72 -50 -30 -10 10
75 74 73 72 71 70 -50 -30 -10 10 30 50 70 90 110 130 150
Temperature (TA ) (°C)
Temperature (TA) (°C)
AP1506 Saturation Voltage vs. Temperature (Vcc = 12V, Vfb = 0V, VSD = 0)
1.6 1.5
AP1506 Switch Current Limit vs. Temperature (Vcc = 12V, Vfb = 0V)
5.5
Saturation Voltage (V)
1.4 1.3 1.2 1.1 1 0.9 0.8 0.7 -50 -25 0 25 1A 0.5A
3A 2A
Switch Current Limit (A)
5 4.5 4 3.5 3 -50
50
75
100
125
-30
-10
10
30
50
70
90
Temperature (TA ) (°C)
Temperature (TA) (°C)
AP1506 Supply Current vs. Temperature (Vcc = 12V, No Load, Von/off = 0V (Switch ON), Von/off = 5V (Switch OFF))
15 14 13 12 11 10 9 8 Sw itch ON 7 6 5 -50 -30 -10 10 30 50
60
Supply Current (mA)
Supply Current (uA)
55 50 45 40 35 30 -50 -30 -10 10 30 50 70 90 110 130 150 Switch OFF
70
90 110 130 150
Temperature (TA ) (°C)
Temperature (TA) (°C)
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Typical Performance Characteristics (Continued)
AP1506 Threshold Voltage vs. Temperature (Vcc = 12V, Io = 100mA)
1.7 1.6 1.5 1.4 1.3 1.2 1.1 1 0.9 0.8 -50 -30 -10 10 30 50 70 90 110 130 150
AP1506 ON/OFF Current vs. ON/OFF Voltage (Vin = 12V)
10 0 -10 -20 -30 -40 -50 -60 -70 -80 -90 - 100 0 3 6 9 12 15 18 21
Threshold Voltage (V)
ON/OFF Current (nA)
AP1506 Frequency vs. Temperature (Vcc = 12V, Io = 500mA, Vout = 5V)
170 165
Temperature (TA) (° C)
ON/OFF Voltage (V)
AP1506 Feedback Current vs. Temperature (Vcc = 12V, Vout = 5V, Vfb = 1.3V)
10
160 155 150 145 140 -50 -30 -10 10 30 50 70 90 110 130 150
Feedback Current (nA)
0 -10 -20 -30 -40 -50 -50 -30 -10 10 30 50 70 90 110 130 150
Frequency (KHz)
Temperature (TA) (°C)
Temperature (TA) (°C)
AP1506 Output Voltage vs. Temperature (Vin = 12V, Io = 3A)
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
Vout (V)
Temperature (TA) (°C)
AP1506 Rev. 2
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Typical Application Circuit
(1) Fixed Type Circuit
(TO packages)
12V DC Input Vin Cin Capacitor 1 5 SD
FB
4
AP1506 - 33 3
2
Output
L1 33uH Inductor D1* Schottky Diode
3.3V/3A Output Load
GND
Co Capacitor
(2) Adjustable Type Circuit
R2 FB 12V DC Input Vin Cin Capacitor 4 1 AP1506 3 GND D1* Schottky Diode Co Capacitor 2 Output L1 47uH 5V/ 3A Output Load R1
5 SD
Vout = VFB × (1 + VFB = 1.23V R2 = 1K ~ 3K (3) Delay Start Circuit
R2 FB 12V DC Input Vin CDELAY C in Capacitor 0.1uF 1 5 SD RDELAY 10K 4
AP1506
R1 R2
)
R1
2 3
Output
L1 47uH
5V/ 3A Output Load
GND
D1* Schottky Diode
Co Capacitor
Note: 3. For up to 2A = DFLS230L (Vf = 0.42V) For up to 3A = B340LA, B340LB (Vf = 0.45V)
AP1506 Rev. 2
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AP1506
150KHz, 3A 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 presented 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 (+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 to a minimum. Feedback (FB) Senses the regulated output voltage to complete the feedback loop. Thermal Considerations The AP1506 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 heat sink depends on the input voltage, the output voltage, the load current and the ambient temperature. The AP1506 junction temperature rises above ambient temperature for a 3A load and different input and output voltages. The data for these curves was taken with the AP1506 (TO-220 package) operating as a buck-switching regulator in an ambient o temperature of 25 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 was designed to be soldering 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 2 be at least 0.8 in , 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 2 6 in , only small improvements in heat dissipation are realized. If further thermal improvements are needed, double sided, multi-layer PC board with large copper areas and/or airflow will be recommended. The AP1506 (TO-263 package) junction temperature rises 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 3A are used, double sided or multi-layer 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, 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.
ON /OFF (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 be wired to the ground pin.
ON / OFF pin can
AP1506 Rev. 2
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Marking Information
(1) TO263-5L
(Top view)
Output Type: 1506: ADJ 1506-33: 3.3V 1506-50: 5.0V 1506-12: 12V
1506-XX YY WW X X
Logo L: Lead Free Package ID code Xth week: 01~52 Year: "01" = 2001 "02" = 2002
~
(2) TO220-5L
(Top view)
Output Type : 1506: ADJ 1506-33: 3.3V 1506-50: 5.0V 1506-12: 12V
1506-XX YY WW X X
Logo L: Lead Free Package ID code Xth week: 01~52 Year: "01" = 2001 "02" = 2002
~
AP1506 Rev. 2
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Package Information
(1) Package Type: TO220-5L
AP1506 Rev. 2
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Package Information (Continued)
(2) Package Type: TO263-5L
AP1506 Rev. 2
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AP1506
150KHz, 3A PWM BUCK DC/DC CONVERTER
Package Information (Continued)
(3) Package Type: TO220-5L(R) Mechanical drawing
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.
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