AP1501
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 37V+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 40V Output load current: 3A Low power standby mode Built-in switching transistor on chip Lead Free packages: TO263-5L and TO220-5L(R) TO263-5L and TO220-5L(R): Available in “Green” Molding Compound (No Br, Sb) Lead Free Finish/RoHS Compliant (Note 1)
General Description
The AP1501 is a fully integrated step-down DC/DC converter, with the ability to drive 3A load without the need of additional driver components. The AP1501 operates at a switching frequency of 150KHZ enabling the use of small size filter components. As a result, board space is reduced and BOM costs are lowered. The AP1501 has integrated the shutdown function that allows standby mode to be activated via an external logic signal input. The internal compensation facilitates feedback control for line and load regulation without the need of an external circuitry. The AP1501 has a built-in Thermal shutdown and Current Limit function to prevent damage from high operating temperature and high current operating to the output switch. Additional features include a guaranteed +/- 4% tolerance on the output voltage under specified input and output load conditions, and +/- 15% on oscillator frequency. The AP1501 offers both fixed and a Adjustable output voltages. For fixed outputs the AP1501 supports 3.3V, 5.0V and 12V. The package options available are standard 5-lead TO263 and TO220(R) packages.
Applications
• • • Simple High-efficiency step-down regulator On-card switching regulators Positive to negative converter
Ordering Information
AP1501 - XX XXX X - X Output version Blank : Adjustable 33 : 3.3V 50 : 5.0V 12 : 12V Package K5 : TO263-5L T5 : TO220-5L T5R : TO220-5L(R) Lead Free L : Lead Free G : Green Packing U : Tube 13 : Tape & Reel
Device
Lead-free
Package Code
K5 K5 K5 K5 T5 T5 T5R T5R
Packaging (Note 2)
TO263-5L TO263-5L TO263-5L TO263-5L TO220-5L TO220-5L TO220-5L(R) TO220-5L(R)
Quantity
50 NA 50 NA 50 50 50 50
Tube Part Number Suffix
-U NA -U NA -U -U -U -U
13” Tape and Reel Quantity Part Number Suffix
NA 800/Tape & Reel NA 800/Tape & Reel NA NA NA NA NA -13 NA -13 NA NA NA NA
Lead-free
Lead-free
Lead-free
AP1501-XXK5L-U AP1501-XXK5L-13 AP1501-XXK5G-U AP1501-XXK5G-13 AP1501-XXT5L-U AP1501-XXT5G-U AP1501-XXT5RL-U AP1501-XXT5RG-U
Notes:
1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied, see EU Directive 2002/95/EC Annex Notes. 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..
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AP1501
150KHz, 3A PWM BUCK DC/DC CONVERTER
Pin Assignments
( Top View ) 5 SD 4 FB 3 Gnd 2 Output 1 VIN
Metal Tab GND
( Top View ) 5 SD 4 FB 3 Gnd 2 Output 1 VIN TO220-5L/TO220-5L(R)
TO263-5L
Pin Descriptions
Name VIN Output Gnd FB SD
Description Operating voltage input Switching output Ground Output voltage feedback control ON/OFF shutdown
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AP1501
150KHz, 3A PWM BUCK DC/DC CONVERTER
Block Diagram
SD
VIN
200mV Current Source bias 1.235V Reference 2.5V Regulator Start up 220mV
+ Comp _
Comp +
FB
Absolute Maximum Ratings
Symbol ESD MM VCC VSD VFB VOUT PD TST TJ
TMJ
Parameter Machine Model ESD Protection Supply Voltage ON/OFF Pin input Voltage Feedback Pin Voltage Output Voltage to Ground Power Dissipation Storage Temperature Operating Junction Temperature Maximum Junction Temperature
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_
+ Amp _
Frequency compensation
Comp +
Pre-driver
150kHz OSC.
Thermal Shutdown
_
3A Switch
Output Gnd
Rating 400 +45 -0.3 to +40 -0.3 to +40 -1 Internally limited -65 to +150 -20 to +125 150
Unit V V V V V W
o o o
C C C
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AP1501
150KHz, 3A PWM BUCK DC/DC CONVERTER
Recommended Operating Conditions
Symbol VOP TA Operating Voltage Operating Ambient Temperature Parameter Rating 4.5 to 40 -20 to 85 Units V
o
C
Electrical Characteristics
(All Output Voltage Versions)
Unless otherwise specified, VIN = 12V for 3.3V, 5V, adjustable version and VIN = 24V 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 VSAT DC ICL
Conditions VFB = 1.3V Feedback Bias Current (Adjustable version only) Oscillator Frequency Saturation Voltage Max. Duty Cycle(ON) Min. Duty cycle(OFF) Current Limit Output = 0 Output Leakage Output = -1 Current Quiescent Current Standby Quiescent Current 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 = 0V force driver on No outside circuit VFB = 12V force driver off (Note 3) VIN = 40V VFB = 12V force driver off ON/OFF pin = 5V VIN = 40V Low (regulator ON)
Parameter
Min
Typ. 40
127 110
150
Max 60 100 173 173 1.4 1.5
Unit nA KHZ V %
1.3 100 0
5.5 3.6 4.0 6.5 200 2 5 150 1.3 15 0.02 37 31 6
o
A uA mA mA uA V
IL IQ ISTBY VIL VIH IH IL θJA
ON/OFF pin Logic Input Threshold Voltage High (regulator OFF) ON/OFF Pin Logic Input Current ON/OFF Pin Input Current Thermal Resistance unction to Ambient VLOGIC = 2.5V (OFF) VLOGIC = 0.5V (ON) TO263-5L (Note 4)
60 10 250 350 0.6
2.0
25 uA 5
o
C/W
TO220-5L(R) (Note 4) TO263-5L (Note 4) TO220-5L(R) (Note 4)
θJC
Thermal Resistance Junction to Case
C/W
5
Notes:
3. Feedback pin removed from output and connected to 0V to force the output transistor switch ON. Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the ADJ. version, and 15V for the 12V version, to force the output transistor switch OFF. 4. Test condition: Device mounted with copper area of approximately 3 in2,1oz, no air flow.
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AP1501
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
Conditions
VMin
Typ.
VMax 1.267 1.28
Unit V
AP1501-ADJ
4.5V < VIN < 40V 1.193 0.2A < ILOAD < 3A 1.18 VOUT programmed for 3V VIN = 12V, ILOAD = 3A 4.75V < VIN < 40V 0.2A < ILOAD < 3A VIN = 12V, ILOAD = 3A 7V < VIN < 40V 0.2A < ILOAD < 3A VIN = 12V, ILOAD = 3A 15V < VIN < 40V 0.2A < ILOAD < 3A VIN = 15V, ILOAD = 3A 11.52 11.4 4.8 4.75 3.168 3.135
1.23
η
VOUT
73 3.3 73 5 80 12 90 12.48 12.6 5.2 5.25 3.432 3.465
% V % V % V %
AP1501-3.3V
η
VOUT
AP1501-5V
η
VOUT
AP1501-12V
η
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AP1501
150KHZ, 3A PWM BUCK DC/DC CONVERTER
Typical Performance Characteristics
Typical Performance Characteristics Normalized Output Voltage
5.10
VIN =20V, I LOAD=3A Normalized at TJ=25oC
Efficiency
100 95
EFFICIENCY (%)
OUTPUT VOLTAGE (V)
5.05
90 85 80 75 70
3A Load
5.00
5V 3.3V
4.95
4.90 -50 -25 0 25 50 75 100 125
65 8 10 15 20 25 30 35 40
JUNCTION TEMPERATURE( oC) JUNCTION TEMPERATURE( oC)
Switch Saturation Voltage
1.60
SATURATION VOLTAGE (V)
Switch Current Limit
5.50
SWITCH CURRENT LIMIT (A)
1.40 1.20 1.00
1 : -40 oC 2 : 25 oC 3 : 125 oC
VIN=12V, VOUT=5V
5.00
4.50
1 0.80 0.60 3 2
4.00
3.50 0.5 1 2 3 -50 -25 0 25 50 75 100 125
SWITCH CURRENT(A) JUNCTION TEMPERATURE( oC)
Operating Quiescent Current
25.0
SUPPLY CURRENT (mA)
Shutdown Quiescent Current
200.0 160.0
CURRENT (uA)
20.0 15.0
Switch ON
10.0 5.0 0.0 -50 -25 0 25 50 75 100 125
120.0 80.0 40.0 0.0
1 2 3
Switch OFF
VON/OFF=5V 1 : -40 oC 2 : 25 oC 3 : 125 oC
20 30 40
10
JUNCTION TEMPERATURE( oC)
SUPPLY VOLOTAGE (V)
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AP1501
150KHz, 3A PWM BUCK DC/DC CONVERTER
Typical Performance Characteristics
Minimum Operating Supply Voltage
5.0
(Continued)
ON/OFF Threshold Voltage
5.0
THRESHOLD VOLTAGE (V)
SUPPLY VOLTAGE (V)
4.0 3.0 2.0 1.0 0.0 -50 -25 0 25 50 75 100 125
4.0 3.0 2.0 1.0 0.0 -50 -25 0 25 50 75 100 125
VOUT=1.23V ILOAD=120mA
JUNCTION TEMPERATURE (oC)
JUNCTION TEMPERATURE (oC)
ON/OFF Pin Current (Sinking)
150.0
FREQUENCY (kHz)
Switch Frequency
200.0
120.0
CURRENT (uA)
VIN=40V -40oC ≤ TJ ≤ 125oC
150.0
90.0 60.0 30.0 0.0 1.4 5 10 15 20 22 23 24 25
ON/OFF PIN VOLTAGE (V)
100.0
50.0
0.0 -50 -25 0 25 50 75 100
o
125
JUNCTION TEMPERATURE ( C)
Feedback Pin Bias Current
50.0
BIAS CURRENT (nA)
40.0 30.0 20.0
Adjustable Version Only
10.0 0.0 -50 -25 0 25 50 75
o
100 125
JUNCTION TEMPERATURE( C)
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AP1501
150KHz, 3A PWM BUCK DC/DC CONVERTER
Typical Application Circuit
(1) Fixed Type Circuit
FB 12V DC Input Vin Cin Capacitor 1 5 SD
4
AP1501 -33
3
2
Output
L1 33uH Inductor D1 B340A
3.3V/3A Output Load
Gnd
Co Capacitor
(2) Adjustable Type Circuit
R2 FB 12V DC Input Vin Cin Capacitor 4 1 AP1501 5 SD 3 Gnd D1 (Note 5) Co Capacitor 2 Output L1 47uH 5V/ 3A Output Load R1
Vout = VFB × (1 + VFB = 1.23V R2 = 1K ~ 3K (3) Delay Start Circuit
R2 FB 12V DC Input Vin Cin Capacitor CDELAY 0.1uF 4 1 5 SD RDELAY 10K AP1501 3 Gnd 2 Output
R1 R2
)
R1
L1 47uH
5V/ 3A Output Load
D1 (Note 5)
Co Capacitor
Notes:
5. Suggested DIODES Power Schottky: B340A or PDS340 series.
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AP1501
150KHz, 3A PWM BUCK DC/DC CONVERTER
Functional 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. 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. Feedback Senses the regulated output voltage to complete the feedback loop. ON/OFF 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 40V) shuts the regulator down. If this shutdown feature is not needed, the ON/OFF 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. Thermal Considerations The AP1501 is available in 5-pin surface mount TO-263 and TO-220. 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 AP1501 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 AP1501 (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 is designed to be soldered 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 2 soldered to should be at least 0.4 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 2 approximately 6 in , only small improvements in heat dissipation are realized. If further thermal improvements are needed, double sided, multilayer PC boards with large copper areas and/or airflow are recommended. The AP1501 (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 2A are used, double sided or multilayer 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. (One 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, multilayer 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.
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AP1501
150KHz, 3A PWM BUCK DC/DC CONVERTER
Marking Information
(1) TO263-5L
( Top View )
Logo Output Type : 1501 : ADJ 1501-33 : 3.3V 1501-50 : 5.0V 1501-12 : 12V
1501-XX YY WW X X
L : Lead Free G : Green ID code Xth week : 01~52 Year : "07" = 2007 "08" = 2008
~
(2) TO220-5L(R)
( Top view )
Logo Output Type : 1501: ADJ 1501-33: 3.3V 1501-50: 5.0V 1501-12: 12V
1501-XX YY WW X X
L : Lead Free G : Green ID code Xth week : 01~52 Year : "07" = 2007 "08" = 2008
~
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AP1501
150KHz, 3A PWM BUCK DC/DC CONVERTER
Package Information
(1) Package Type: TO263-5L
(2) Package Type: TO220-5L
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AP1501
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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