2A/3A PWM Buck DC/DC Converter

AP1512/A 50KHz, 2A/3A PWM Buck DC/DC Converter Features - Output voltage: 3.3V, 5V, 12V and adjustable output version - Adjustable version output voltage range, 1.23V to 37V+4% - 50KHz +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 60V - Output load current: 2A (for AP1512) 3A (for AP1512A) - Low power standby mode - Built-in switching transistor on chip - TO220-5L, TO220-5L(R) and TO263-5L Pb-free packages General Description The AP1512/A is a monolithic IC that design for a step-down DC/DC converter, and own the ability of driving a 2A (3A for AP1512A) 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 AP1512/A operates at a switching frequency of 50KHz 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 Assignments ( Top View ) 5 SD 4 FB 3 Gnd 2 Output 1 VIN Pin Descriptions Name VIN Output Gnd FB SD Description Operating voltage input Switching output Ground Output voltage feedback control ON/OFF Shutdown Metal Tab GND TO263-5L ( 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. 14, 2005 1/12 AP1512/A 50KHz, 2A/3A PWM Buck DC/DC Converter Ordering Information AP1512 X XX X X Part Number Blank: 2A A : 3A Output Version Blank : Adjustable -33 : 3.3V -50 : 5.0V -12 : 12V Package T5: TO220-5L T5R: TO220-5L(R) K5: TO263-5L Packing Blank : Tube A : Taping Block Diagram SD VIN 200mV Current Source bias 1.235V Reference 2.5V Regulator Start up 220mV Comp _ + Comp + FB Comp + Anachip Corp. www.anachip.com.tw 2/12 _ + Amp _ Frequecy compensation Pre-driver 50KHz OSC. Thermal Limit _ 2A Switch (3A for AP1512A) Output Gnd Rev.1.1 Oct. 14, 2005 AP1512/A 50KHz, 2A/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 Rating +63 -0.3 to +40 -0.3 to +40 -1 Internally limited -65 to +150 -40 to +125 +4.5 to +60 Unit V V V V W o C o C V Electrical Characteristics (All Output Voltage Versions) Unless otherwise specified, VIN=30V for all version. ILOAD = 0.5A Symbol IB FOSC VSAT DC ICL ICL IL IQ ISTBY VIL VIH IH IL θJC θJA Parameter Feedback bias current oscillator frequency Conditions VFB=1.3V (Adjustable version only) Min. Typ. 5 42.5 40 50 1.3 100 0 IOUT=2A 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 for AP1512 no outside circuit VFB=0V force driver on peak current current limit for AP1512A no outside circuit VFB=0V force driver on Output no outside circuit Output = 0 leakage VFB=12V force driver off VIN=60V Output = -1 current Quiescent Current VFB=12V force driver off Standby Quiescent ON/OFF pin=5V Current VIN=60V Low (regulator ON) ON/OFF pin logic input threshold voltage High (regulator OFF) ON/OFF pin logic VLOGIC=2.5V (OFF) input current ON/OFF pin input current VLOGIC=0.5V (ON) Junction to TO220-5L Thermal Resistance case TO263-5L TO220-5L Thermal Resistance Junction to With copper area of ambient TO263-5L 2 approximately 3 in saturation voltage Max. 8 10 57.5 60 1.4 1.5 Unit µA KHz V % 2.5 3.2 3 4 4.5 5.5 5 6 -250 A A uA mA mA uA V uA o -2 5 350 2.0 1.3 0 -0.8 2.5 3.5 28 23 -60 10 450 500 0.6 -5 -10 C/W C/W o Anachip Corp. www.anachip.com.tw 3/12 Rev.1.1 Oct. 14, 2005 AP1512/A 50KHz, 2A/3A PWM Buck DC/DC Converter Electrical Characteristics (Continued) AP1512 Symbol AP1512-ADJ AP1512-3.3V AP1512-5V VFB VOUT VOUT VOUT η Parameter Output Feedback Output voltage Output voltage Output voltage Efficiency Parameter Output Feedback Output voltage Output voltage Conditions 10V < VIN < 60V 0.2A < ILOAD < 2A VOUT programmed for 3V 10V < VIN < 60V 0.2A < ILOAD < 2A 10V < VIN < 60V 0.2A < ILOAD < 2A 15V < VIN < 60V 0.2A < ILOAD < 2A VIN = 30V, ILOAD = 2A Conditions 10V < VIN < 60V 0.2A < ILOAD VOUT programmed for 3V 10V < VIN < 60V 0.2A < ILOAD 10V < VIN < 60V 0.2A < ILOAD Typ. 1.23 3.3 5 12 83 Typ. 1.23 3.3 5 Limit 1.193/1.18 1.267/1.28 3.168/3.135 3.432/3.465 4.8/4.75 5.2/5.25 11.52/11.4 12.48/12.6 Unit V VMIN VMAX V VMIN VMAX V VMIN VMAX V VMIN VMAX % Unit V VMIN VMAX V VMIN VMAX V VMIN VMAX V VMIN VMAX % AP1512-12V AP1512A Symbol AP1512A-ADJ AP1512A-3.3V AP1512A-5V VFB VOUT VOUT Limit 1.193/1.18 1.267/1.28 3.168/3.135 3.432/3.465 4.8/4.75 5.2/5.25 AP1512A-12V VOUT η Output voltage Efficiency 15V < VIN < 60V 0.2A < ILOAD VIN = 30V, ILOAD = 3A 12 80 11.52/11.4 12.48/12.6 Specifications with boldface type are for full operating temperature range, the other type are for TJ=25ºC. Typical Performance Characteristics AP1512A Current Limit v.s. Temperature (Vcc=60V, Vout=5V) 4 3.8 Current Limit (A) 3.6 3.4 3.2 3 -50 Efficiency(%) AP1512A Efficiency v.s. Supply Voltage (Vout=5V, Iout=3A) 100 90 80 70 60 50 40 30 20 10 0 0 12 24 36 Supply Voltage(V) 48 60 0 50 100 150 Temperature (TA) (°C) Anachip Corp. www.anachip.com.tw 4/12 Rev.1.1 Oct. 14, 2005 AP1512/A 50KHz, 2A/3A PWM Buck DC/DC Converter Typical Performance Characteristics (Continued) AP1512 Efficiency v.s. Temperature (Vin=12V,Vout=5V,Io=2A) 100 90 80 70 AP1512 Efficiency v.s. Temperature (Vin=12V,Vout=3.3V,Io=2A) 100 90 80 70 60 50 40 30 20 10 0 -50 -30 -10 10 30 Efficiency (%) 60 50 40 30 20 10 0 -50 -30 -10 10 30 50 70 90 110 130 150 Efficiency (%) 50 70 90 110 130 150 Temperature (TA) (°C) Temperature (TA) (°C) AP1512 Supply Current v.s. Temperature (Vcc=12V , No Load ,Von/off =0V(Switch ON) ,Von/off =5V(Switch OFF)) 8 100 90 Switch ON Supply Current (mA) 6 5 4 3 2 1 0 -40 -25 -10 5 Supply Current (uA) 7 80 70 60 50 40 30 20 10 0 Switch OFF 20 35 50 65 80 95 110 125 -40 -25 -10 5 20 35 50 65 80 95 110 125 Temperature (TA) (°C) Temperature (TA) (°C) AP1512 Output Voltage v.s. Temperature (Vin=12V, Vout=5V, Io=1A) 5.10 5.05 AP1512 Threshold Voltage v.s. Temperature (Vcc=12V, Vout=5V) 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 -50 0 50 100 150 Output Voltage (V) 5.00 4.95 4.90 4.85 4.80 4.75 4.70 -50 0 50 100 Temperature (TA) (°C) 150 Threshold Voltage (V) Temperature (TA) (°C) Anachip Corp. www.anachip.com.tw 5/12 Rev.1.1 Oct. 14, 2005 AP1512/A 50KHz, 2A/3A PWM Buck DC/DC Converter Typical Performance Characteristics (Continued) AP1512 Frequency v.s. Temperature (Vcc=12V, Io=1A, Vout=5V) 60 AP1512 Current Limit v.s. Temperature (Vcc=60V, Vout=5V) 3.6 Frequency (KHz) 55 50 Current Limit (A) -50 -30 -10 10 30 50 70 90 110 130 150 3.4 3.2 45 3 40 2.8 -50 0 50 100 150 Temperature (TA) (°C) Temperature (TA) (° AP1512 Quiescent Current v.s. Supply Voltage (force driver off) 6.2 Quiescent Current (A) 6 5.8 5.6 5.4 5.2 0 12 24 36 48 60 Supply Voltage(V) Anachip Corp. www.anachip.com.tw 6/12 Rev.1.1 Oct. 14, 2005 AP1512/A 50KHz, 2A/3A PWM Buck DC/DC Converter Typical Application Circuit (1) Adjustable Type Circuit A. Vin=10V~60V, Vout=5V; Iout=0.3A~2A, Iout below 0.3A DCM Vin 1 Vin OUTPUT 2 1 L1 47uH 2 Vout AP1512/A 5 C1 100uF/100V C2 1u ON/OFF SD GND 3 FB 4 D1 SR360 R2 3K C5 1n C7 0.1u C3 470uF/16V R3 1K B. Vin=10V~60V, Vout=3.3V, Iout=0.3A~2A, Iout below 0.3A DCM Vin 1 Vin OUTPUT 2 1 L1 47uH 2 Vout AP1512/A 5 C1 100uF/100V C2 1u ON/OFF SD GND 3 FB 4 D1 SR360 R2 2K C5 1n C7 0.1u C3 470uF/16V R3 1.2K (2) Fixed Type Circuit A. Vin=10V~60V, Vout=5V, Iout=0.7A~2A, Iout below 0.7A DCM Vin 1 Vin OUTPUT 2 1 L1 47uH 2 Vout AP1512/A 5 C1 100uF/100V C2 1u ON/OFF SD GND 3 FB 4 D1 SR360 C7 10n C3 470uF/16V Anachip Corp. www.anachip.com.tw 7/12 Rev.1.1 Oct. 14, 2005 AP1512/A 50KHz, 2A/3A PWM Buck DC/DC Converter Typical Application Circuit (Continued) B. Vin=10V~60V, Vout=3.3V, Iout=0.7A~2A, Iout below 0.7A DCM Vin 1 Vin OUTPUT 2 1 L1 33uH 2 Vout AP1512/A 5 C1 220uF/100V C2 3.3u ON/OFF SD GND 3 FB 4 D1 SR360 C7 3.3u C3 1500uF/16V Function Description +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 curr