Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 GENERAL DESCRIPTION The APE1705 series are monolithic IC designed for a step-down DC/DC converter, and own the ability of driving a 3A load without additional transistor. It saves board space. The external shutdown function can be controlled by logic level and then come into standby mode. The internal compensation makes feedback control having 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. If current limit function occurs and VFB is down below 0.5V, the switching frequency will be reduced. The APE1705 series operates at a switching frequency of 150KHz thus allow 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 chips are available in a 5-Lead TO-263 and 5-Lead TO-220 package. FEATURES - Output voltage: 3.3V, 5V, 12V and adjustable output version. - Adjustable version output voltage range, 1.23V to 38.5V. - 150KHz 15% fixed switching frequency. - Voltage mode non-synchronous PWM control. Thermal-shutdown and current-limit protection. ON/OFF shutdown control input. Short Circuit Protect (SCP). Operating voltage can be up to 40V. Output load current: 3A. 5-Lead TO-263 and TO-220 Pb-Free packages. Low power standby mode. Built-in switching transistor on chip. This datasheet contains new product information. Advanced Power Electronics 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. 1 200801173 Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 BLOCK DIAGRAM EN 200mV V CC 220mV CURRENT SOURCE BIAS 1.235V REFERENCE START UP 2.5V REGULATOR + _ COMP. Current limit 150kHz OSC. _ FB COMP. + R2 + AMP _ + COMP. _ COMP. CONTROL + DRIVER 3A SWITCH R1 SW Thermal Shutdown Vss ADJ : R2=0, R1=OPEN PIN ASSIGNMENT The package of APE1705 are TO263-5L and TO220-5L(R); the pin assignment is given by: Name TO263-5L ( Side View ) 5 EN 4 FB/OUT 3 VSS 2 SW 1 VCC Metal Tab GND ( Top View ) VCC Operating voltage input SW Switching output VSS GND pin FB Output voltage feedback control for ADJ version OUT Output voltage feedback control EN TO220-5L ( Side View ) ( Top View ) ON/OFF Shutdown TO220-5LR ( Side View ) 5 EN 4 FB/OUT 3 VSS 2 SW 1 VCC Metal Tab GND Description 5 EN 4 FB/OUT 3 VSS 2 SW 1 VCC Metal Tab GND ( Top View ) 2 Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 ORDER INFORMATION Order Information APE1705X -XX Package Type Output Voltage 33:3.3V S: TO263-5L 50:5.0V P :TO220-5L 12: 12V PR:TO220-5L-R Blank:ADJ MARKING INFORMATION Top Marking ADJ 1705X YWWSSS Part number ID code: internal WW: 01~52 Year : 6 = 2006 FIX 1705X -50 YWWSSS Part number Output Voltage ID code: internal WW: 01~52 Year : 6 = 2006 3 Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 Absolute Maximum Ratings Characteristics Symbol Rating Unit Maximum Supply Voltage VCC +45 V ON/OFF Pin Input Voltage VEN -0.3 to 40 V Feedback Pin Voltage (for ADJ version) VFB -0.3 to 20 V Output Voltage to Ground (for Fixed version) VOUT 0.7 to 45 V Power Dissipation Internally limited PD ( TJ-TA ) / JA W Storage Temperature Range TST -65 to +150 Operating Temperature Range TOP -40 to +125 Operating Supply Voltage VOP +4.5 to +40 V Thermal Resistance from Junction to case JC TO263=3.5,TO220=3.5 /W Thermal Resistance from Junction to ambient JA TO263=25,TO220=25 /W Note : JA is measured with the PCB copper area(need connect to VSS pins) of approximately 3 in2 (Multi-layer). Electrical Characteristics (Unless otherwise specified, Ta=25C, VCC=12V for 3.3V, 5V, adjustable version and VCC=18V for the 12V version. ILOAD = 0.2A) Characteristics Symbol Quiescent Current ICCQ Feedback bias current IFB Shutdown supply Current ISD Oscillator frequency FOSC Oscillator frequency of short circuit protect FSCP Max. Duty Cycle (ON) DC Min. Duty Cycle (OFF) Current limit ICL Load Regulation( VOUT/VOUT ) VOUT Saturation voltage SW pin=0V SW pin=-0.8V VSA T SW pin leakage current ISW L Conditions VFB=12V force driver off VFB=1.3V (Adjustable version only) EN pin=5V VCC=40V EN pin logic input current EN pin input current IL VEN=0.5V (ON) Thermal shutdown Temp TSD 4 8 mA -50 nA -100 200 uA 300 173 KHz KHz KHz 150 60 60 100 % 0 3.5 - IOUT=3A, No outside circuit VFB=0V force driver on No outside circuit VFB=12V force driver off VCC=40V force driver off Low (regulator ON) High (regulator OFF) VEN=2.5V (OFF) Max Units 100 (Adjustable) When VFB<0.5V (Fixed)When < VOUT*40% VFB=0V force driver on VFB=12V force driver off Pear current, No outside circuit V FB=0V force driver on IOUT = 0.2 to 3A Typ -10 127 VIL VIH IH EN pin logic input threshold voltage Min A 0.6 1.3 1.2 1.4 1.5 % -200 uA -5 2.0 mA -0.1 0.6 -5 -0.01 -1 1.3 135 V V uA 4 Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 Electrical Characteristics (Continued) version Characteristics Symbol Conditions Min Typ Max Units 1.267 V 4.5V < VCC < 40V Output Feedback 0. 2A < ILOAD < 3A 1.193 VOUT programmed /1.180 V FB APE1705-ADJ voltage 1.23 /1.280 for 3V Efficiency Output voltage V OUT APE1705-3.3V Efficiency Output voltage V OUT APE1705-5.0V Efficiency Output voltage V OUT APE1705-12V Efficiency VCC = 12V, ILOAD=3A 74 4.75V < VCC < 40V 3.168 0.2A < ILOAD < 3A /3.135 3.432 V 3.3 /3.465 75 VCC = 12V, ILOAD=3A 7V < VCC < 40V 4.80 0.2A < ILOAD < 3A /4.75 VCC = 12V, ILOAD=3A 5.0 % 5.20 11.52 0.2A < ILOAD < 3A /11.40 V /5.25 80 15V < VCC < 40V VCC = 24V, ILOAD = 3A % % 12.48 V 12 /12.60 89 % Specifications with boldface type are for full operating temperature range, the other type are for TJ=25C. 5 Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 Application Circuit (1) VIN=12V VIN=12V 1 Vcc 2 SW C1 470uF L1 1 4 C2 0.1uF 5 Vout=5.0V/3A 2 33uH U1 Vss FB 3 R1 4.7K D1 B340A C3 470uF C6 0.1uF EN R2 1.5K ON/OFF (2) VIN=24V VIN=24V L1 1 47uH U1 1 Vcc 2 SW C1 470uF 4 C2 0.1uF 5 Vout=5.0V/3A 2 Vss 3 R1 4.7K D1 B340A FB C3 470uF C6 0.1uF EN Vout = VFB x (1 + R1 R2 R2 1.5K ), VFB = 1.23V, R2 = 0.7K ~ 3K VOUT R2 R1 5.0V 1.5K 4.7K 3.3V 1.5K 2.5K 2.5V 1.5K 1.5K (3) Fixed Output Voltage Version VIN=24V L1 1 U1 1 Vcc 2 SW C1 470uF 4 C2 0.1uF 5 Vout=5.0V/3A 2 47uH Vss 3 FB D1 B340A C3 470uF C6 0.1uF EN L1 recommend value (IOUT=3A,) VOUT 2.5V 3.3V 5V 12V VIN=12V 33uH 33uH 33~47uH NA VIN=24V 33uH 33uH 47uH 68uH 6 Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 Function Descriptions Pin Functions Vcc 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. Vss Circuit ground. SW Internal switch. The voltage at this pin switches between (+VCC - VSAT) and approximately - 0.5V, with a duty cycle of approximately VOUT / VCC. To minimize coupling to sensitive circuitry, the PC board copper area connected to this pin should be minimized. Feedback Senses the regulated output voltage to complete the feedback loop. EN Allows the switching regulator circuit to be shutdown using logic level signals thus dropping the total input supply current to approximately 100uA. 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 Vcc) shuts the regulator down. If this shutdown feature is not needed, the EN pin can be wired to the ground pin. Thermal Considerations The TO-263-5L 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 APE1705 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 APE1705 (TO263-5L package) operating as a buck-switching regulator in an ambient temperature of 25 (still air). These temperature increments are all approximate and are affected by many factors. Higher ambient temperatures requires more heat sinker. 7 Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 Function Descriptions (Continued) For the best thermal performance, wide copper traces and generous amounts of printed circuit board copper (need connect to the VSS pins) should be used in the board layout, (One exception is the SW(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 increments are all approximate. The increments are affected by a lot of factors. 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 Advanced Power Electronics Corp. 150KHz, 3A PWM Buck DC/DC Converter APE1705 Typical Characteristics Output Ripple Power on test wave (VIN=12V, VOUT=5V, IOUT=3A) (VIN=12V, VOUT=5V, IOUT=3A ) VOUT VOUT (AC) VIN SW SW ISW ISW Load Transient Response EN on test wave (VIN=12V, VOUT=5V, IOUT=0.2~3A) (VIN=12V, VOUT=5V, IOUT=3A ) VOUT (AC) VOUT VIN SW SW ISW ISW Efficiency Efficiency (VIN=12V, VOUT=5.0V) (VIN=24V, VOUT=5.0V) Vin=12V Vin=12V 90% 90% 80% 80% 70% Efficiency(%) Efficiency(%) 70% 60% 50% 40% 30% 60% 50% 40% 30% 20% 20% 10% 10% 0% 0% 0.0 0.5 1.0 1.5 2.0 Iout(A) 2.5 3.0 0.0 0.5 1.0 1.5 2.0 Iout(A) 2.5 3.0 9 ADVANCED POWER ELECTRONICS CORP. Package Outline : TO-263-5L Millimeters SYMBOLS MIN NOM MAX A 4.40 4.60 4.80 b 0.66 0.79 0.91 L4 0.00 0.15 0.30 c 0.36 0.43 0.50 L1 2.29 2.54 2.79 E 9.80 10.10 10.40 7.60 E1 c2 1.25 1.35 1.27 L2 D 8.60 8.80 D1 5.90 e 1.70 L 1.45 9.00 14.60 15.20 15.80 0 4 8 1.All Dimensions Are in Millimeters. 2.Dimension Does Not Include Mold Protrusions. Part Marking Information & Packing : TO-263-5L Part Number Output Voltage 1705S-XX LOGO Package Code YWWSSS Date Code (YWWSSS) YLast Digit Of The Year WWWeek SSSSequence 10 ADVANCED POWER ELECTRONICS CORP. Package Outline : TO-220-5L Millimeters SYMBOLS MIN NOM MAX A 4.07 4.45 4.82 b 0.76 0.89 1.02 C D E e 0.36 0.50 0.64 14.22 14.86 15.50 9.78 10.16 10.54 1.57 1.71 1.85 e1 6.68 6.81 6.93 F 1.14 1.27 1.40 H1 5.46 6.16 6.86 J1 2.29 2.74 3.18 L 13.21 13.97 14.73 p Q 3.68 3.81 3.94 2.54 2.73 2.92 1.All Dimensions Are in Millimeters. 2.Dimension Does Not Include Mold Protrusions. Part Marking Information & Packing : TO-220-5L Part Number 1705P-XX LOGO YWWSSS Output Voltage Package Code Date Code (YWWSSS) YLast Digit Of The Year WWWeek SSSSequence 11 ADVANCED POWER ELECTRONICS CORP. Package Outline : TO-220-5LR Millimeters SYMBOLS MIN NOM MAX A 4.40 4.6 4.70 b 0.70 0.80 0.90 D 8.40 8.70 8.90 d1 1.00 d2 6.30 E 9.91 10.16 10.41 e 1.60 1.70 1.80 F 1.20 1.25 1.30 H1 6.40 H2 20.8 21.60 22.4 H3 23.90 24.70 25.50 J1 3.7 4.50 5.3 J2 Q 8.40 2.50 2.80 3.00 1.All Dimension Are In Millimeters. 2.Dimension Does Not Include Mold Protrusions. Part Marking Information & Packing : TO-220-5LR Part Number Package Code 1705PR-XX LOGO Output Voltage YWWSSS Date Code (YWWSSS) YLast Digit Of The Year WWWeek SSSSequence 12