AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER General Description Features • • • • • • • • • • • • • The AP1501A series are monolithic ICs that are designed for a step-down DC/DC converter, and possess the ability to drive a 5A 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. The AP1501A 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 includes fixed 3.3V, 5V, 12V, and an adjustable type. The packages are available in a standard 5-lead TO263 and TO220 packages. 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: 5A Low power standby mode Built-in switching transistor on chip Lead Free packages: TO263-5L and TO220-5L(R) TO263-5L: Available in “Green” Molding Compound (No Br, Sb) Lead Free Finish/RoHS Compliant (Note 1) Applications • • • Simple High-efficiency step-down regulator On-card switching regulators Positive to negative converter Ordering Information AP1501A - XX XXX X - X Output Version Package Blank : Adjustable 33 : 3.3V 50 : 5.0V 12 : 12V K5 : TO263-5L T5 : TO220-5L T5R : TO220-5L(R) Device Lead-free Lead-free Lead-free AP1501A-XXK5L-U AP1501A-XXK5L-13 AP1501A-XXK5G-U AP1501A-XXK5G-13 AP1501A-XXT5L-U AP1501A-XXT5RL-U Package Packaging Code (Note 2) K5 K5 K5 K5 T5 T5R TO263-5L TO263-5L TO263-5L TO263-5L TO220-5L TO220-5L(R) Lead Free L : Lead Free G : Green Tube Quantity Part Number Suffix 50 NA 50 NA 50 50 Packing -U NA -U NA -U -U U : Tube 13 : Tape & Reel 13” Tape and Reel Part Number Quantity Suffix NA 800/Tape & Reel NA 800/Tape & Reel NA NA NA -13 NA -13 NA NA Lead-free 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. AP1501A Rev. 7 1 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER Pin Assignments ( Top View ) ( Top View ) 5 SD 4 FB 3 Gnd 2 Output 1 VIN Metal Tab GND 5 SD 4 FB 3 Gnd 2 Output 1 VIN TO220-5L/TO220-5L(R) TO263-5L Pin Descriptions Description Name VIN Output Gnd Operating voltage input Switching output Ground FB Output voltage feedback control SD ON/OFF shutdown AP1501A Rev. 7 2 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER Block Diagram SD VIN 200mV Current Source bias 1.235V Reference 2.5V Regulator 220mV Start up + Comp _ _ Comp + Freq. Compensation _ FB + Amp _ Comp + 5A Switch Pre-driver Output 150kHz OSC. Thermal Shutdown Gnd Absolute Maximum Ratings Symbol Rating Unit Machine Model ESD Protection 400 V VCC Supply Voltage +45 V VSD ON/OFF Pin input voltage -0.3 to +40 V VFB Feedback Pin voltage -0.3 to +40 V VOUT Output voltage to Ground -1 V ESD MM PD TST TJ AP1501A Rev. 7 Parameter Power dissipation Internally limited Storage temperature Operating Junction Temperature 3 of 12 www.diodes.com W -65 to +150 o -20 to +125 o C C SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER Recommended Operating Conditions Symbol VOP Parameter Rating Operating voltage TA Units 4.5 to 40 Operating Ambient Temperature Electrical Characteristics V o -20 to 85 C ( 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 Parameter Feedback Bias Current FOSC Oscillator Frequency VSAT Saturation Voltage DC Max. Duty Cycle(ON) Min. Duty Cycle(OFF) ICL Current Limit IL IQ ISTBY VIL VIH IH IL θJA θJC Notes: Output Leakage Output = -1V Current Quiescent Current Standby Quiescent Current Output = 0V Conditions VFB = 1.3V (Adjustable version only) IOUT = 5A 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 (Note 3) VIN = 40V VFB = 12 force driver off ON/OFF pin = 5V VIN = 40V Thermal Resistance Junction-to-Ambient Thermal Resistance Junction-to-Case Typ. 40 127 110 Low (regulator ON) ON/OFF Pin Logic Input Threshold Voltage High (regulator OFF) ON/OFF Pin Logic Input Current ON/OFF Pin Input Current Min 150 1.5 Max 60 100 173 173 1.6 Unit nA Khz V 1.7 100 0 % 6.5 5.5 6.0 2 5 150 A 7.5 200 uA 60 10 250 300 mA mA uA 0.6 1.3 V 2.0 VLOGIC = 2.5V (OFF) 15 25 VLOGIC = 0.5V (ON) 0.02 5 TO263-5L (Note 4) 37 uA o C/W TO220-5L(R) (Note 4) 31 TO263-5L (Note 4) 6 TO220-5L(R) (Note 4) 5 o C/W 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 3in2, 1oz, no air flow. AP1501A Rev. 7 4 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A 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 Parameter Conditions Typ. Limit Unit VFB Output Feedback 5V < VIN < 40V 0.2A < ILOAD < 5A VOUT programmed for 3V 1.23 1.193/1.18 1.267/1.28 V VMIN VMAX η Efficiency VIN = 12V, ILOAD=5A 72 VOUT Output Voltage 5.5V < VIN < 40V 0.2A < ILOAD < 5A 3.3 η Efficiency VIN = 12V, ILOAD=5A 71 VOUT Output Voltage 8V < VIN < 40V 0.2A < ILOAD < 5A 5 η Efficiency VIN = 12V, ILOAD = 5A 78 VOUT Output Voltage 15V < VIN < 40V 0.2A < ILOAD < 5A 12 η Efficiency VIN = 16V, ILOAD = 5A 88 AP1501A-ADJ AP1501A-3.3V AP1501A-5V AP1501A-12V AP1501A Rev. 7 5 of 12 www.diodes.com % 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 % SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER Typical Performance Characteristics Typical Performance Characteristics Normalized Output Voltage Efficiency 100 VIN =20V, ILOAD=3A Normalized at TJ = 25°C 5.05 95 EFFICIENCY (%) OUTPUT VOLTAGE CHANGE 5.10 5.00 5A Load 90 85 5V 80 75 4.95 70 4.90 3.3V 65 -50 -25 0 25 50 75 100 125 8 10 15 JUNCTION TEMPERATURE(°C) SWITCH CURRENT LIMIT (A) SATURATION VOLTAGE (V) 1.5 1.4 1 1.3 1.2 40 7.5 VIN =12V, VOUT =5V 7.0 6.5 6.0 2 3 5.5 2.0 4 3 5 -50 -25 25 50 75 100 125 Shutdown Quiescent Current Operating Quiescent Current 200.0 20.0 160.0 CURRENT (uA) 25.0 15.0 Switch ON 10.0 Switch OFF 5.0 0 JUNCTION TEMPERATURE(°C) SWITCH CURRENT(A) SUPPLY CURRENT (mA) 35 Switch Current Limit 1 : -40o C 2 : 25 o C 3 : 125o C 1.6 30 25 INPUT VOLTAGE Switch Saturation Voltage 1.7 20 120.0 80.0 1 2 V ON/OFF=5V 1 : -40 o C 2 : 25 o C 3 : 125 o C 3 40.0 0.0 -50 -25 0 25 50 75 100 125 AP1501A Rev. 7 0.0 10 20 30 40 SUPPLY VOLTAGE (V) JUNCTION TEMPERATURE(°C) 6 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER Typical Performance Characteristics (Continued) ON/OFF Threshold Voltage Minimum Operating Supply Voltage 5.0 THRESHOLD VOLTAGE (V) SUPPLY VOLTAGE (V) 5.0 4.0 3.0 2.0 VOUT=1.23V ILOAD=120mA 1.0 3.0 2.0 1.0 0.0 0.0 -50 -25 0 25 50 -50 -25 75 100 125 0 25 50 75 100 125 JUNCTION TEMPERATURE (oC) JUNCTION TEMPERATURE (oC) ON/OFF Pin Current (Sinking) Switch Frequency 200.0 150.0 FREQUENCY (kHz) VIN=40V -40oC ≤ TJ ≤ 125oC 120.0 CURRENT (uA) 4.0 90.0 60.0 150.0 100.0 50.0 30.0 0.0 0.0 1.4 5 10 15 20 22 23 24 25 -50 -25 0 25 50 75 100 125 JUNCTION TEMPERATURE (oC) ON/OFF PIN VOLTAGE (V) Feedback Pin Bias Current BIAS CURRENT (nA) 50.0 40.0 30.0 20.0 Adjustable Version Only 10.0 0.0 -50 -25 0 25 50 75 100 125 JUNCTION TEMPERATURE(oC) AP1501A Rev. 7 7 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER Typical Application Circuit (1) Fixed Type Circuit FB 12V DC Input L1 18uH 4 Vin AP1501A 2 -33 1 5 3.3V/5A Output Load Inductor 3 SD Cin Capacitor Output D1 Schottky Diode Gnd Co Capacitor (2) Adjustable Type Circuit R1 R2 FB 12V DC Input L1 22uH 4 Vin 1 AP1501A 2 5 SD Cin Capacitor Output 5V/ 5A Output Load 3 Gnd Vout = VFB × (1 + R1 D1 Schottky Diode Co Capacitor ) R2 VFB = 1.23V R2 = 1K ~ 3K (3) Delay Start Circuit R2 R1 FB 12V DC Input Vin Cin Capacitor AP1501A Rev. 7 L1 22uH 4 CDELAY 0.1uF 1 AP1501A 2 5 Output 5V/ 5A Output Load 3 SD RDELAY 10K Gnd D1 Schottky Diode 8 of 12 www.diodes.com Co Capacitor SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A 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 AP1501A is available in two packages, a 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 AP1501A junction temperature rises above ambient temperature for a 5A load and different input and output voltages. The data for these curves was taken with the AP1501A (TO-220 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. The AP1501A (TO-263 package) junction temperature rise 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 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. (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, 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. 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 2 the package is soldered to should 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 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. AP1501A Rev. 7 9 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER Marking Information (1) TO263-5L ( Top View ) Logo Output Type : 1501A : ADJ 1501A-33 : 3.3V 1501A-50 : 5.0V 1501A-12 : 12V 1501A 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 ) Output Type: 1501A : ADJ 1501A33 : 3.3V 1501A50 : 5.0V 1501A12 : 12V Logo 1501AXX YY WW X X L : Lead Free Package ID code Xth week: 01~52 Year: "07" = 2007 "08" = 2008 ~ AP1501A Rev. 7 10 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A PWM BUCK DC/DC CONVERTER Package Information (All Dimensions in mm) (1) Package Type: TO263-5L (2) Package Type: TO220-5L AP1501A Rev. 7 11 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated AP1501A 150KHz, 5A 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. AP1501A Rev. 7 12 of 12 www.diodes.com SEPTEMBER 2008 © Diodes Incorporated