AP1501 150Khz, 3A PWM Buck DC/DC Converter Features General Description - 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 - TO220-5L TO220-5L(R) and TO263-5L packages - Low power standby mode - Built-in switching transistor on chip The AP1501 series are monolithic IC that design for a step-down DC/DC converter, and own the ability of driving a 3A 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 AP1501 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 fixed 3.3V, 5V, 12V, and an adjustable type. The packages are available in a standard 5-lead TO-220 package and a 5-lead TO-263. Applications - Simple High-efficiency step-down regulator - On-card switching regulators - Positive to negative converter Pin Descriptions Pin Assignments Name ( Top View ) Metal Tab GND VIN 5 SD 4 FB 3 Gnd 2 Output 1 VIN Output Gnd TO263-5L Description Operating voltage input Switching output Ground FB Output voltage feedback control SD ON/OFF Shutdown ( Top View ) 5 SD 4 FB 3 Gnd 2 Output 1 VIN TO220-5L This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sale of the product. Rev.1.1 Oct. 29, 2004 1/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Ordering Information AP1501 XX X X X Package Output version Lead Free Packing Blank : Normal T5: TO220-5L T5R: TO220-5L(R) L : Lead Free Package K5: TO263-5L Blank : Adjustable -33 : 3.3V -50 : 5.0V -12 : 12V Blank : Tube A : Taping Block Diagram SD VIN 200mV Current Source bias 1.235V Reference 2.5V Regulator 220mV Start up + Comp _ _ Comp + Frequecy compensation _ FB + Amp _ Comp + Pre-driver 3A Switch Output 150kHz OSC. Anachip Corp. www.anachip.com.tw Thermal Shutdown Gnd Rev.1.1 Oct. 29, 2004 2/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Absolute Maximum Ratings Symbol Parameter Rating Unit +45 V ON/OFF Pin input voltage -0.3 to +25 V Feedback Pin voltage -0.3 to +25 V VCC Supply Voltage VSD VFB VOUT Output voltage to Ground PD Power dissipation TST Storage temperature -1 V Internally limited W -65 to +150 o C o C TOP Operating temperature -40 to +125 VOP Operating voltage +4.5 to +40 V 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 Symbol IFB Parameter Feedback bias current FOSC oscillator frequency VSAT saturation voltage DC Max. Duty Cycle(ON) Conditions VFB=1.3V (Adjustable version only) IOUT=3A no outside circuit VFB=0V force driver on VFB=0V force driver on IQ Quiescent Current VFB=12V force driver off ISTBY Standby Quiescent Current ON/OFF pin=5V VIN=40V IL VIL VIH IH IL current limit Output = 0 ON/OFF pin logic input threshold voltage Low (regulator ON) High (regulator OFF) ON/OFF pin logic VLOGIC=2.5V (OFF) input current ON/OFF pin input current VLOGIC=0.5V (ON) JC Thermal Resistance JA Thermal Resistance With copper area of approximately 3 in2 40 127 Output leakage Output = -1 current ICL Typ. 150 110 VFB=12V force driver off peak current no outside circuit VFB=0V force driver on no outside circuit VFB=12V force driver off VIN=40V Min. Duty cycle(OFF) Min. TO220-5L TO263-5L TO220-5L TO263-5L 1.3 Unit 60 nA 100 173 173 Khz 1.4 V 1.5 100 % 0 3.6 4.0 A 6.5 uA 2 60 mA 5 10 mA 150 2.0 5.5 200 250 uA 300 0.6 1.3 25 0.02 5 2.5 Junction to ambient 28 3.5 23 V - 15 Junction to case Anachip Corp. www.anachip.com.tw Max. uA o C/W o C/W Rev.1.1 Oct. 29, 2004 3/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Electrical Characteristics (Continued) Symbol AP1501-ADJ AP1501-3.3V Typ. Limit Unit 1.23 1.193/1.18 1.267/1.28 V VMIN VMAX Output Feedback 4.5V < VIN < 40V 0.2A < ILOAD < 3A VOUT programmed for 3V Efficiency VIN = 12V, ILOAD=3A 73 Output voltage 4.75V < VIN < 40V 0.2A < ILOAD < 3A 3.3 Efficiency VIN = 12V, ILOAD=3A 73 Output voltage 7V < VIN < 40V 0.2A < ILOAD < 3A 5 Efficiency VIN = 12V, ILOAD=3A 80 Output voltage 15V < VIN < 40V 0.2A < ILOAD < 3A 12 Efficiency VIN = 15V, ILOAD = 3A 90 VOUT VOUT AP1501-12V Conditions VFB AP1501-5V Parameter VOUT % 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 % Specifications with boldface type are for full operating temperature range, the other type are for TJ=25C. Anachip Corp. www.anachip.com.tw Rev.1.1 Oct. 29, 2004 4/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Typical Performance Characteristics Typical Performance Characteristics Normalized Output Voltage Efficiency 100 5.10 OUTPUT VOLTAGE (V) VIN =20V, I LOAD=3A Normalized at TJ=25oC 95 EFFICIENCY (%) 5.05 5.00 4.95 3A Load 90 85 5V 80 75 3.3V 70 4.90 -50 -25 0 25 50 75 100 65 125 8 10 JUNCTION TEMPERATURE( C) Switch Saturation Voltage 1.20 1.00 1 0.80 0.60 35 40 TEMPERATURE( oC) VIN=12V, VOUT=5V 5.00 4.50 4.00 2 3 3.50 0.5 2 1 3 -50 -25 200.0 20.0 160.0 CURRENT (uA) 25.0 Switch ON 10.0 Switch OFF 5.0 25 50 75 100 125 Shutdown Quiescent Current Operating Quiescent Current 15.0 0 JUNCTION TEMPERATURE( oC) SWITCH CURRENT(A) SUPPLY CURRENT (mA) 30 25 5.50 1 : -40 oC 2 : 25 oC 3 : 125 oC 1.40 20 Switch Current Limit SWITCH CURRENT LIMIT (A) SATURATION VOLTAGE (V) 1.60 15 JUNCTION o 120.0 80.0 1 2 VON/OFF=5V 1 : -40 oC 2 : 25 oC 3 : 125 oC 3 40.0 0.0 -50 -25 0 JUNCTION 25 50 75 100 125 0.0 TEMPERATURE( oC) 10 20 30 40 SUPPLY VOLOTAGE (V) Anachip Corp. www.anachip.com.tw Rev.1.1 Oct. 29, 2004 5/12 AP1501 150Khz, 3A 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 75 100 125 -50 -25 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 -50 -25 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 o JUNCTION TEMPERATURE( C) Anachip Corp. www.anachip.com.tw Rev.1.1 Oct. 29, 2004 6/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Typical Application Circuit (1) Fixed Type Circuit FB 12V DC Input L1 33uH 4 AP1501 -33 1 Vin 5 2 3.3V/3A 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 47uH 4 1 Vin AP1501 5 SD Cin Capacitor 2 Output 5V/ 3A Output Load 3 Gnd Vout = VFB x (1 + D1 Schottky Diode R1 R2 Co Capacitor ) VFB = 1.23V R2 = 1K ~ 3K (3) Delay Start Circuit R2 R1 FB 12V DC Input 4 Vin Cin Capacitor CDELAY 0.1uF 1 AP1501 5 2 Output L1 47uH 5V/ 3A Output Load 3 SD RDELAY 10K Gnd D1 Schottky Diode Anachip Corp. www.anachip.com.tw Co Capacitor Rev.1.1 Oct. 29, 2004 7/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Function Description all approximate and there are many factors that can affect these temperatures. Higher ambient temperatures require more heat sinking. 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. 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 soldered to should be at least 0.4 in2, 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 6 in2, only small improvements in heat dissipation are realized. If further thermal improvements are needed, double sided, multilayer PC board with large copper areas and/or airflow are recommended. 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. The AP1501 (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 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. 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 25V) 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 two packages, a 5-pin TO-220 and a 5-pin surface mount TO-263. 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. The TO-220 package needs a heat sink under most conditions. The size of the heatsink 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 temperature of 25oC (still air). These temperature rise numbers are Anachip Corp. www.anachip.com.tw Rev.1.1 Oct. 29, 2004 8/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Function Description (Continued) 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. 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. Marking Information (1) TO263-5L (2) TO220-5L ( Top view ) ( Top view ) Output Type: 1501: ADJ 1501-33: 3.3V 1501-50: 5.0V 1501-12: 12V Output Type: 1501: ADJ 1501-33: 3.3V 1501-50: 5.0V 1501-12: 12V Logo 1501-XX YY WW X X Blank: normal L: Lead Free Package ID code Xth week: 01~52 Year: "01" = 2001 "02" = 2002 Logo 1501-XX YY WW X X Blank: normal L: Lead Free Package ID code Xth week: 01~52 Year: "01" = 2001 "02" = 2002 ~ ~ Anachip Corp. www.anachip.com.tw Rev.1.1 Oct. 29, 2004 9/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Package Information (1) Package Type: TO220-5L E A F L D H1 Q P b e C J1 e1 Symbol A b C D E e e1 F H1 J1 L Op Q Dimensions In Millimeters Min. Nom. Max. 4.07 4.45 4.82 0.76 0.89 1.02 0.36 0.50 0.64 14.22 14.86 15.50 9.78 10.16 10.54 1.57 1.71 1.85 6.68 6.81 6.93 1.14 1.27 1.40 5.46 6.16 6.86 2.29 2.74 3.18 13.21 13.97 14.73 3.68 3.81 3.94 2.54 2.73 2.92 Anachip Corp. www.anachip.com.tw Dimensions In Inches Min. Nom. Max. 0.160 0.030 0.014 0.175 0.035 0.020 0.190 0.040 0.025 0.560 0.385 0.062 0.263 0.045 0.215 0.090 0.520 0.145 0.100 0.585 0.400 0.067 0.268 0.050 0.243 0.108 0.550 0.150 0.107 0.610 0.415 0.073 0.273 0.055 0.270 0.125 0.580 0.155 0.115 Rev.1.1 Oct. 29, 2004 10/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Package Information (Continued) (2) Package Type: TO263-5L E 2.5 L D 15.7 9.1 L2 10.9 1.0 1.7 C2 A Land Pattern Recommendation (Unit: mm) B C e L1 Symbol A B C C2 D E e L L1 L2 Dimensions In Millimeters Min. Nom. Max. 4.07 4.46 4.85 0.66 0.84 1.02 0.36 0.50 0.64 1.14 1.27 1.40 8.65 9.15 9.65 9.78 10.16 10.54 1.57 1.71 1.85 14.61 15.24 15.88 2.29 2.54 2.79 2.92 Anachip Corp. www.anachip.com.tw Dimensions In Inches Min. Nom. Max. 0.160 0.176 0.191 0.026 0.033 0.040 0.014 0.020 0.025 0.045 0.050 0.055 0.341 0.360 0.380 0.385 0.400 0.415 0.062 0.068 0.073 0.575 0.600 0.625 0.090 0.100 0.110 0.115 Rev.1.1 Oct. 29, 2004 11/12 AP1501 150Khz, 3A PWM Buck DC/DC Converter Package Information (Continued) (3) Package Type: TO220-5L(R) Mechanical drawing A E F Q H1 D d1 H2 H3 d2 J1 b J2 e J3 J3 J2 A J1 E Symbol A b D d1 d2 E e F H1 H2 H3 J1 J2 J3 Q Dimensions In Millimeters Min. Nom. Max. 4.4 4.6 4.7 0.7 0.8 0.9 8.4 8.7 8.9 1.0 6.3 9.91 10.16 10.41 1.6 1.7 1.8 1.2 1.25 1.3 6.4 20.8 21.6 22.4 23.9 24.7 25.5 2.7 3.7 4.5 5.3 8.4 2.5 2.8 3.0 Anachip Corp. www.anachip.com.tw Dimensions In Inches Min. Nom. Max. 0.175 0.180 0.185 0.027 0.032 0.037 0.330 0.340 0.350 0.039 0.248 0.390 0.400 0.410 0.062 0.067 0.072 0.048 0.050 0.052 0.250 0.820 0.850 0.880 0.942 0.972 1.002 0.105 0.147 0.177 0.207 0.331 0.100 0.110 0.120 Rev.1.1 Oct. 29, 2004 12/12