AP1507 150KHz, 3A PWM BUCK DC/DC CONVERTER General Description 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 • • • • • • • • ON /OFF Shutdown Control Input Operating Voltage can be up to 22V Output Load Current: 3A Lead Free Package: TO252-5L Low Power Standby Mode Built-in Switching Transistor On Chip Lead Free Package: TO252-5L Lead Free Finish/RoHS Compliant (Note 1) • The AP1507 is a monolithic IC designed for a step-down DC/DC converter and is capable of driving a 3A load without an external transistor. Due to reducing the number of external components, 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 the feedback control have good line and load regulation without an external design. Regarding the protected function, the thermal shutdown is to prevent over temperature operating from damaging the device, and current limit is against over current operating of the output switch. If the current limit function occurred and VFB is down to 0.5V below, the switching frequency will be reduced. The AP1507 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 a fixed 3.3V, 5V, 12V, and an adjustable type. AP1507 is available in a 5-lead TO-252 lead-free package. Applications • • • Simple High-Efficiency Step-Down Regulator On-Card Switching Regulators Positive to Negative Converter Ordering Information AP1507 - XX X X X Note: 1. Output Version Package Lead Free Packing Blank : Adjustable 33 : 3.3V 50 : 5.0V 12 : 12V D5: TO252-5L L : Lead Free -U : Tube -13 : Taping RoHS revision 13.2.2003. Glass and High Temperature Solder Exemptions Applied, see EU Directive Annex Notes 5 and 7. Lead-free Device Package Code Packaging (Note 2) AP1507-XXD5 D5 TO252-5L Tube/Bulk Part Number Quantity Suffix 80 -U 13” Tape and Reel Part Number Quantity Suffix 2500/Tape & Reel 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. AP1507 Rev. 1 1 of 10 www.diodes.com FEBRUARY 2007 © Diodes Incorporated -13 AP1507 150KHz, 3A PWM BUCK DC/DC CONVERTER Pin Descriptions Pin Assignments (Top View) Name Description VIN 5 SD 4 FB 3 GND 2 Output 1 VIN Operating Voltage Input Output GND Metal Tab GND Switching Output Ground FB Output Voltage Feedback Control SD ON /OFF Shutdown TO252-5L Block Diagram SD VIN 200mV Current Source Bias 1.235V Reference 2.5V Regulator 220mV Start Up + Comp _ _ Comp + + Amp _ Frequency Compensation _ FB PreDriver Comp + 3A Switch Output 150kHz OSC. AP1507 Rev. 1 2 of 10 www.diodes.com Thermal Shutdown GND FEBRUARY 2007 © Diodes Incorporated AP1507 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 Electrical Characteristics Rating +24 Unit V -0.3 to +18 V -0.3 to +18 -1 Internally Limited -65 to +150 -40 to +125 +4.5 to +22 V V W o C o C V (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 ILEAK IQ ISTBY VIL VIH Parameter Feedback Bias Current Conditions VFB = 1.3V ( Adjustable Version Only ) Oscillator Frequency When current limit Occurred and VFB < 0.5V, Ta = 25 oC IOUT = 3A 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 = 0V leakage VFB =12V Force Driver Off current VIN = 22V Output = -1V Quiescent Current VFB = 12V Force Driver Off Standby Quiescent ON /OFF Pin = 5V Current VIN = 22V ON /OFF Pin Logic Input Low (Regulator ON) High (Regulator OFF) Threshold Voltage Oscillator Frequency of Short Circuit Protect IH ON /OFF Pin Logic Input Current IL ON /OFF Pin Input Current VLOGIC = 0.5V (ON) Junction to Thermal Resistance TO252-5L Case Thermal Resistance Junction to TO252-5L with copper area of Ambient approximately 2cm ×2cm ΘJC ΘJA AP1507 Rev. 1 Min. Typ. -10 127 110 150 10 30 Unit 50 KHz nA KHz 1.6 1.4 V 1.7 100 0 3.6 4.5 % 5.5 A 6.5 -200 -5 5 70 2.0 1.3 VLOGIC = 2.5V (OFF) 3 of 10 www.diodes.com Max. -50 -100 173 173 uA mA mA 10 150 200 0.6 - uA V -0.01 -0.1 uA -1 10 o 50 o C/W C/W FEBRUARY 2007 © Diodes Incorporated AP1507 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. AP1507-ADJ AP1507-3.3V AP1507-5V AP1507-12V AP1507 Rev. 1 Symbol Parameter Conditions VMin Typ VMax Unit VFB Output Feedback 5V < VIN < 22V 0.2A < ILOAD < 3A VOUT Programmed for 3V 1.193 1.18 1.23 1.267 1.28 V η Efficiency VIN = 12V, ILOAD = 3A VOUT Output Voltage 5.5V < VIN < 22V 0.2A < ILOAD < 3A η Efficiency VIN = 12V, ILOAD = 3A VOUT Output Voltage 8V < VIN < 22V 0.2A < ILOAD < 3A η Efficiency VIN = 12V, ILOAD = 3A VOUT Output Voltage 15V < VIN < 22V 0.2A < ILOAD < 3A η Efficiency VIN = 16V, ILOAD = 3A 4 of 10 www.diodes.com 74 3.168 3.135 3.3 % 3.432 3.465 75 4.8 4.75 5 % 5.2 5.25 80 11.52 11.4 12 89 V V % 12.48 12.6 V % FEBRUARY 2007 © Diodes Incorporated AP1507 150KHz, 3A PWM BUCK DC/DC CONVERTER Typical Performance Characteristics AP1507 Efficiency vs. Temperature (Vin = 12V, Vout = 3.3V, Io = 3A) 78 83 82 81 80 79 78 77 76 75 74 73 72 77 76 Efficiency (%) Efficiency (%) AP1507 Efficiency vs. Temperature (Vin = 12V, Vout = 5V, Io = 3A) 75 74 73 72 71 70 -50 -30 -10 10 30 50 70 90 110 130 150 -50 -30 -10 10 Temperature (TA) (°C) AP1507 Saturation Voltage vs. Temperature (Vcc = 12V, Vfb = 0V, VSD = 0) 50 70 90 110 130 150 AP1507 Switch Current Limit vs. Temperature (Vcc = 12V, Vfb = 0V) 1.6 Switch Current Limit (A) 5.5 1.5 Saturation Voltage (V) 30 Temperature (TA) (°C) 3A 1.4 1.3 2A 1.2 1A 1.1 0.5A 1 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) AP1507 Supply Current vs. 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 50 45 Switch OFF 40 35 30 -50 -30 -10 10 30 50 70 90 110 130 150 Temperature (TA) (°C) Temperature (TA) (°C) AP1507 Rev. 1 55 5 of 10 www.diodes.com FEBRUARY 2007 © Diodes Incorporated AP1507 150KHz, 3A PWM BUCK DC/DC CONVERTER Typical Performance Characteristics (Continued) AP1507 Threshold Voltage vs. Temperature (Vcc = 12V, Io = 100mA) AP1507 ON/OFF Current vs. 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) 10 165 0 155 150 145 9 12 15 18 21 AP1507 Feedback Current vs. Temperature (Vcc = 12V, Vout = 5V, Vfb = 1.3V) 170 160 6 ON/OFF Voltage (V) Feedback Current (nA) Frequency (KHz) AP1507 Frequency vs. Temperature (Vcc = 12V, Io = 500mA, Vout = 5V) 3 -10 -20 -30 -40 -50 140 -50 -30 -10 10 30 50 70 90 110 130 150 Temperature (TA) (°C) -50 -30 -10 10 30 50 70 90 110 130 150 Temperature (TA) (°C) Vout (V) AP1507 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 AP1507 Rev. 1 0 20 40 60 80 100 120 140 160 Temperature (TA) (°C) 6 of 10 www.diodes.com FEBRUARY 2007 © Diodes Incorporated AP1507 150KHz, 3A PWM BUCK DC/DC CONVERTER Typical Application Circuit (1) Fixed Type Circuit FB 12V DC Input L1 33uH 4 AP1507 -33 1 Vin 5 2 3.3V/3A Output Load Inductor 3 D1 Schottky Diode GND SD Cin Capacitor Output Co Capacitor (2) Adjustable Type Circuit R1 R2 FB 12V DC Input L1 47uH 4 1 Vin 5 SD Cin Capacitor 2 AP1507 Output 5V/ 3A 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 AP1507 Rev. 1 L1 47uH 4 CDELAY 0.1uF 1 2 AP1507 5 Output 5V/ 3A Output Load 3 SD RDELAY 10K GND D1 Schottky Diode 7 of 10 www.diodes.com Co Capacitor FEBRUARY 2007 © Diodes Incorporated AP1507 150KHz, 3A PWM BUCK DC/DC CONVERTER Applications Information 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 at a minimum. Feedback (FB) Senses the regulated output voltage to complete the feedback loop. 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 ON /OFF pin can be wired to the ground pin. Thermal Considerations The TO-252 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 soldered 2 to should be at least 0.8 in , and ideally should have 2 or more square inches of 2 oz. additional copper area which improves the thermal characteristics. 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, multi-layer PC board with large copper areas and/or airflow will be recommended. AP1507 Rev. 1 The AP1507 (TO-252 package) junction temperature rises above ambient temperature with a 3A 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 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. (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, 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. 8 of 10 www.diodes.com FEBRUARY 2007 © Diodes Incorporated AP1507 150KHz, 3A PWM BUCK DC/DC CONVERTER Marking Information TO252-5L (Top view) Part Number Output Type: Blank: Adjustable 33: 3.3V 50: 5.0V 12: 12V 1507 - XX X X X X XX Logo L: Lead Free Package ID Code Xth Week:01~52 Year: "01" = 2001 "02" = 2002 ~ Package Information ( in mm ) Package Type: TO252-5L AP1507 Rev. 1 9 of 10 www.diodes.com FEBRUARY 2007 © Diodes Incorporated AP1507 150KHz, 3A PWM BUCK DC/DC CONVERTER 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. AP1507 Rev. 1 10 of 10 www.diodes.com FEBRUARY 2007 © Diodes Incorporated