Advanced Power Electronics Corp. APE1720 200KHz, 1.5A PWM Buck DC/DC Converter GENERAL DESCRIPTION The APE1720 series are monolithic IC designed for a step-down DC/DC converter, and own the ability of driving a 1.5A 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 APE1720 series operates at a switching frequency of 200KHz thus allow smaller sized filter components than what would be needed with lower frequency switching regulators. Other features include a guaranteed +3% tolerance on output voltage under specified input voltage and output load conditions, The chips are available in a standard 8-lead SOP package. FEATURES - Output voltage: adjustable output version. - Adjustable version output voltage range: 0.75V to 22V+3%. - 200KHz 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 24V. - Output load current: 1.5A. - SOP-8L 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. 200828071pre-1/7 Advanced Power Electronics Corp. APE1720 BLOCK DIAGRAM EN 200mV V CC 220mV CURRENT SOURCE BIAS 0.75V 2.5V REGULATOR REFERENCE START UP + _ COMP. Current limit 200KHz OSC. + + CONTROL + DRIVER COMP. _ FB _ + AMP _ COMP. COMP. SW Vss Thermal Shutdown PIN ASSIGNMENT The package of APE1720 is SOP-8L; the pin assignment is given by: Name ( Top View ) Description VCC Operating voltage input SW Switching output VSS FB Output voltage feedback control VSS EN ON/OFF Shutdown HIGH：ON, LOW：OFF VSS GND pin VCC 1 8 VSS SW 2 7 VSS FB 3 6 EN 4 5 APE1720M SOP-8L ORDER/MARKING INFORMATION Order Information APE1720X Package Type M: SOP-8L Top Marking 1720M YWWSSS Part number ID code: internal WW: 01~52 Year : 7 = 2007 2/7 Advanced Power Electronics Corp. APE1720 Absolute Maximum Ratings Characteristics Symbol Rating Unit Maximum Supply Voltage VCC +26 V ON/OFF Pin Input Voltage VEN -0.3 to VCC V Feedback Pin Voltage VFB -0.3 to 12 V Output Voltage to Ground VOUT -0.8 V Power Dissipation Internally limited PD ( TJ-TA ) / θJA W Storage Temperature Range TST -65 to +150 ℃ Operating Temperature Range TOP -20 to +125 ℃ Operating Supply Voltage VOP +4.0 to +24 V Thermal Resistance from Junction to case θJC 20 ℃/W Thermal Resistance from Junction to ambient θJA 55 ℃/W Note : θJA is measured with the PCB copper area(need connect to VSS pins) of approximately 1.5 in2 (Multi-layer). Electrical Characteristics (Unless otherwise specified, Ta=25°C, VCC=12V. ILOAD = 0.2A) Characteristics Symbol Conditions Feedback Voltage VFB IOUT=0.2A Quiescent Current IQ VFB=1.2V force driver off Feedback bias current IFB IOUT=0.1A Shutdown supply Current ISD VEN =0V Oscillator frequency Oscillator frequency of short circuit protect Max. Duty Cycle (ON) Min. Duty Cycle (OFF) Current limit SW pin=-0.8V DC VSA T SW pin leakage current ISW L EN pin logic input current VIH VIL IH High (regulator ON) Low (regulator OFF) VEN=2.5V (ON) EN pin input current IL VEN=0.3V (OFF) EN pin logic input threshold voltage Thermal shutdown Temp TSD Max Units V 4 8 mA -10 -50 nA - 2 10 uA 140 200 260 KHz 80 KHz VFB=1.2V force driver off VFB=0V force driver on Pear current, No outside circuit V FB=0V force driver on IOUT=1.5A, No outside circuit VFB=0V force driver on No outside circuit VFB=1.0V force driver off VCC=24V force driver off Typ 0.728 0.750 0.773 FSCP (Adjustable) When VFB<0.5V ICL Saturation voltage SW pin=0V FOSC Min 0 % 100 1.8 A 1.2 1.5 V -200 uA -5 mA 0.5 1.2 2.0 - - 20 - - -5 - 135 V uA ℃ 3/7 Advanced Power Electronics Corp. APE1720 Application Circuit (1) Adjustable Output Voltage Version C1 220uF Vout=5V/1.5A L1 VIN=12V 1 2 3 4 C2 0.1uF U1 APE1720 Vcc Vss 8 SW Vss 7 FB Vss 6 EN Vss 5 33uH D1 B240A R1 6.8K C3 C6 220uF 0.1uF R2 1.2K (2) EN PIN With Delayed Startup C1 220uF Vout=5V/1.5A L1 VIN=12V C2 0.1uF 1 2 3 4 R3 100k U1 APE1720 Vcc Vss 8 SW Vss 7 FB Vss 6 EN Vss 5 33uH D1 B240A R1 6.8K C3 C6 220uF 0.1uF R2 1.2K ON/OFF C4 0.1uF Vout = VFB × (1 + R1 R2 ), VFB = 0.75V , R2 = 0.75K ~ 4K Table 1 Resistor select for output voltage setting VOUT R2 R1 5V 1.2K 6.8K 3.3V 2K 6.8K 2.5V 2K 4.7K 1.8V 2K 3K 1.5V 2K 2K 1.3V 2K 1.5K 1.2V 2K 1.2K 4/7 Advanced Power Electronics Corp. APE1720 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 10uA. Pulling this pin below a threshold voltage of approximately 0.5V shuts the regulator down, and pulling this pin above 2.0V (up to a maximum of Vcc) turns the regulator on. Thermal Considerations The SOP-8 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 APE1720 junction temperature rises above ambient temperature for a 1.5A load and different input and output voltages. For the best thermal performance, wide copper traces and generous amounts of PCB copper (need connect to the VSS pins) should be used in the board layout, (One exception is the SW 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. 5/7 Advanced Power Electronics Corp. APE1720 Typical Characteristics VFB VS VIN ICCQ VS VIN VFB VS VIN Iccq VS VIN 0.77 6.00 0.76 5.00 4.00 Iccq(mA) VFB(V) 0.75 0.74 0.73 3.00 2.00 0.72 1.00 0.71 0.00 4 6 4 8 10 12 14 16 18 20 22 24 26 Vin(V) FOSC VS VIN 6 8 10 12 14 16 18 20 22 24 26 Vin(V) FOSC VS TEMPERATURE Fosc VS VIN FOSC VS TEMP 240 220 FOSC(KHz) Fosc(KHz) 230 210 200 190 180 4 6 240 230 220 210 200 190 180 170 160 150 140 -20 8 10 12 14 16 18 20 22 24 26 Vin(V) 0 20 60 80 100 120 temp (℃ ) VFB VS TEMPERATURE ICCQ VS TEMPERATURE VFB VS TEMP ICCQ VS TEMP 6.00 0.763 5.00 ICCQ(mA) 0.760 VFB(V) 40 0.757 0.754 0.751 4.00 3.00 2.00 1.00 0.748 0.00 0.745 -20 0 20 40 60 80 100 120 temp (℃) -20 0 20 40 60 80 100 120 temp (℃ ) 6/7 Advanced Power Electronics Corp. APE1720 Typical Characteristics Output Ripple Power on test wave (VIN=12V, VOUT=3.3V, IOUT=1.5A) (VIN=12V, VOUT=3.3V, IOUT=1.5A) VOUT VOUT(AC) VIN VIN SW SW ISW ISW Load Transient Response EN PIN on test wave (VIN=12V, VOUT=3.3V, IOUT=0.1~1.5A) (VIN=12V, VOUT=3.3V, IOUT=1.5A) VOUT VOUT(AC) VIN VIN SW SW ISW ISW Efficiency Efficiency (VIN=12V, VOUT=5V) (VIN=12V) Vin=12V 90% 80% 80% 70% 70% 60% 60% Efficiency(%) Efficiency(%) Vin=12V 90% 50% 40% 30% 50% 40% 20% 20% 10% 10% 0% 0.0 0.5 Iout(A) 1.0 1.5 Vout=5V Vout=3.3V Vout=2.5V Vout=1.8V Vout=1.2V 30% 0% 0.0 0.5 Iout(A) 1.0 1.5 7/7 ADVANCED POWER ELECTRONICS CORP. Package Outline : SOP-8L D 8 7 Millimeters 6 2 MIN NOM MAX A 1.35 1.55 1.75 A1 0.10 0.18 0.25 B 0.33 0.41 0.51 C 0.19 0.22 0.25 D 4.80 4.90 5.00 E1 3.80 3.90 4.00 E 5.80 6.15 6.50 L 0.38 0.71 1.27 θ 0 4.00 8.00 5 E1 1 SYMBOLS 3 E 4 e e B 1.27 TYP A A1 DETAIL A L 1.All Dimension Are In Millimeters. 2.Dimension Does Not Include Mold Protrusions. c DETAIL A Part Marking Information & Packing : SOP-8L Part Number Package Code 1720M YWWSSS Date Code (YWWSSS) Y：Last Digit Of The Year WW：Week SSS：Sequence θ