AP1513

AP1513 PWM CONTROL 2A STEP-DOWN CONVERTER Features • • • • • • • • • Input voltage: 3.6V to 18V Output voltage: 0.8V to VCC Duty ratio: 0% to 100% PWM control Oscillation frequency: 300KHz typ. Soft-start, Current limit, Enable function Thermal Shutdown function Built-in internal SW P-channel MOS SOP-8L: Available in “Green” Molding Compound Lead Free Finish/RoHS Compliant for Lead Free and “Green” products (Note 1) General Description AP1513 consists of step-down switching regulator with PWM control. These devices include a reference voltage source, oscillation circuit, error amplifier, and internal PMOS. AP1513 provides low-ripple power, high efficiency, and excellent transient characteristics. The PWM control circuit is able to vary the duty ratio linearly from 0 up to 100%. This converter also contains an error amplifier circuit as well as a soft-start circuit that prevents overshoot at startup. An enable function, an over current protect function and a short circuit protect function are built inside, and when OCP or SCP happens, the operation frequency will be reduced from 300KHz to 30KHz. Also, an internal compensation block is built in to minimum external component count. With the addition of an internal P-channel Power MOS, a coil, capacitors, and a diode connected externally, these ICs can function as step-down switching regulators. They serve as ideal power supply units for portable devices when coupled with the SOP–8L mini-package, providing such outstanding features as low current consumption. Since this converter can accommodate an input voltage up to 18V, it is also suitable for the operation via an AC adapter. Applications • • • • • • • • • PC Motherboard LCD Monitor Graphic Card DVD-Video Player Telecom Equipment ADSL Modem Printer and other Peripheral Equipment Microprocessor core supply Networking power supply Ordering Information AP1513 X X X Package S : SOP-8L Lead-Free L : Lead-Free G : Green Packing - U : Tube -13 : Taping Note: 1. RoHS revision 13.2.2003. Glass and High Temperature Solder Exemptions Applied, see EU Directive Annex Notes 5 and 7. Device (Note 2) AP1513S Note: Tube/Bulk Package Packaging Quantity Part Number Code Suffix S SOP-8L 100 -U 13” Tape and Reel Quantity Part Number Suffix 2500/Tape & Reel -13 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. AP1513 Rev. 1 1 of 8 www.diodes.com JANUARY 2007 © Diodes Incorporated AP1513 PWM CONTROL 2A STEP-DOWN CONVERTER Pin Assignments Pin Descriptions (Top View) FB 1 EN 2 AP1513 OCSET 3 VCC 4 6 5 Output Output 8 Vss 7 Vss Pin Pin Description Name No. FB 1 Feedback pin Power-off pin H: Normal operation EN 2 (Step-down operation) L: Step-down operation stopped (All circuits deactivated) Add an external resistor to set max OCSET 3 output current VCC 4 IC power supply pin Switch Pin. Connect external Output 5, 6 inductor/diode here. Minimize trace area at this pin to reduce EMI VSS 7, 8 GND Pin Block Diagram Output Oscillation Circuit V CC _ + PWM-Switched Control Circuit Thermal Shutdown VEN EN 100uA Vss FB Reference Voltage Source with Soft Start OCSET AP1513 Rev. 1 2 of 8 www.diodes.com JANUARY 2007 © Diodes Incorporated AP1513 PWM CONTROL 2A STEP-DOWN CONVERTER Absolute Maximum Ratings Symbol VCC VFB VEN VOUT PD TJ TSTG Caution: Parameter VCC Pin Voltage Feedback Pin Voltage EN Pin Voltage Switch Pin Voltage Power Dissipation Junction Temperature Range Storage Temperature Range Rating VSS - 0.3 to VSS + 20 VSS - 0.3 to VCC VSS - 0.3 to VIN + 0.3 VSS - 0.3 to VIN + 0.3 Internally limited -40 to +125 -40 to +150 Unit V V V V mW o o C C The absolute maximum ratings are rated values exceeding which the product could suffer physical damage. These values must therefore not be exceeded under any conditions. Electrical Characteristics Symbol VIN VFB IFB ISW ISSS ∆VOUT /VOUT ∆VOUT /VOUT fOSC fOSC1 VSH VSL ISH ISL IOCSET TSS RDSON EFFI θJA Parameter Input Voltage Feedback Voltage Feedback Bias Current Switch Current Current Consumption During Power Off Line Regulation Load Regulation Oscillation Frequency Frequency of Current Limit or Short Circuit Protect EN Pin Input Voltage EN Pin Input Leakage Current OCSET Pin Bias Current Soft-Start Time Internal MOSFET Rdson Efficiency Thermal Resistance Junction-to-Ambient ( VIN = 12V, TA = 25°C, unless otherwise specified ) Conditions -IOUT = 0.1A IOUT = 0.1A -VEN = 0V VIN = 5V~18V IOUT = 0.1 to 2A Measure waveform at SW pin Measure waveform at SW pin Evaluate oscillation at SW pin Evaluate oscillation stop at SW pin ----VIN=5V, VFB=0V VIN=12V, VFB=0V VIN=12V, VOUT = 5V IOUT=2A Min. 3.6 0.784 2.5 240 10 2.0 75 0.3 - Typ. 0.8 0.1 10 1 0.2 300 20 -10 90 2 110 70 92 65 Max. 18 0.816 0.5 2 0.5 400 0.8 105 5 150 100 - Unit V V µA A µA % % KHz KHz V µA µA µA ms mΩ % o C/W AP1513 Rev. 1 3 of 8 www.diodes.com JANUARY 2007 © Diodes Incorporated AP1513 PWM CONTROL 2A STEP-DOWN CONVERTER Typical Application Circuit VOUT=5V/2A RA 6.8K VIN ROCSET COCSET 3K Option CIN 470uF CVcc 0.1uF REN 100K CEN 0.1uF Vcc L1 Output 33uH CC Optional FB VSS D1 RB 1.3K AP1513 OCSET EN + - C + - COUT 470uF 0.1uF Note: VOUT = VFB x (1+RA/RB) RB=0.7K~5K ohm Figure 1. VIN = 12V, IMAX = 2A 2.5V 3.3V 22uH 27uH 5V 33uH VOUT L1 Value Typical Performance Characteristics AP1513 Vin vs. Frequency (Vout=3.3V; Iout=0.2A) 350 345 340 Fosc (KHz) 330 325 320 315 310 0 335 2 4 6 8 10 12 Vin (V) 14 16 18 20 0.84 0.83 0.82 0.81 0.80 0.79 0.78 0.77 0.76 0.75 0.74 0 AP1513 Vin vs. FB (Vout=3.3V; Iout=0.2A) FB (V) 2 4 6 8 Vin (V) 10 12 14 16 18 20 AP1513 Rev. 1 4 of 8 www.diodes.com JANUARY 2007 © Diodes Incorporated AP1513 PWM CONTROL 2A STEP-DOWN CONVERTER Typical Performance Characteristics ( Continued ) 3.40 3.35 AP1513 Line Regulation (Vout=3.3V; Iout=0.2A) 3.25 3.20 3.15 3.10 Vout (V) Vout (V) 3.30 5.10 5.09 5.08 5.07 5.06 5.05 5.04 5.03 5.02 5.01 5.00 0.0 AP1513 Load Regulation (Vin=12V) 0 2 4 6 8 Vin (V) 10 12 14 16 18 20 0.5 1.0 Iout (A) 1.5 2.0 2.5 AP1513 Efficiency 100 90 80 70 60 50 40 30 20 10 0 0.0 0.5 1.0 Efficiency (%) Vout:5.0V Vout:3.3V 1.5 2.0 Iout (A) AP1513 Vout Ripple ( Vin = 12V; Vout = 3.3V; Iout = 0.1A ) AP1513 Vout Ripple ( Vin = 12V; Vout = 3.3V; Iout = 2A ) AP1513 Rev. 1 5 of 8 www.diodes.com JANUARY 2007 © Diodes Incorporated AP1513 PWM CONTROL 2A STEP-DOWN CONVERTER Test Circuit open VCC OUTPUT FB open Oscillation A 1K A VCC OUTPUT FB OCSET EN VSS 1K + - OCSET EN VSS Enable function test 33K Feedback function test 3K + - VCC OUTPUT FB 6.8K OCSET EN VSS + - V 1.2K Operation function test Function Description PWM Control The AP1513 consists of DC/DC converters that employ a pulse-width modulation (PWM) system. In converters of the AP1513, the pulse width varies in a range from 0 to 100%, according to the load current. The ripple voltage produced by the switching can easily be removed through a filter because the switching frequency remains constant. Therefore, these converters provide a low-ripple power over broad ranges of input voltage and load current. Under Voltage Lockout The under voltage lockout circuit of the AP1513 assures that the high-side MOSFET driver outputs remain in the off state whenever the supply voltage drops below 3.3V. Normal operation resumes once VCC rises above 3.5V. RDS(ON) Current Limiting The current limit threshold is setting by the external resistor connecting from VCC supply to OCSET. The internal 100uA sink current crossing the resistor sets the voltage at the pin of OCSET. When the PWM voltage is less than the voltage at OCSET, an over-current condition is triggered. ILOAD × RDS(ON) = IOCSET × ROCSET See above formula for setting the current limit value. AP1513 Rev. 1 6 of 8 www.diodes.com JANUARY 2007 © Diodes Incorporated AP1513 PWM CONTROL 2A STEP-DOWN CONVERTER Marking Information (1) SOP-8L ( Top View ) 8 5 Logo Part no. AP1513 YY WW X X Blank : Lead Free Package G : Green Package Internal code Xth week: 01~52 Year: "01" =2001 "02" =2002 ~ 1 4 Device AP1513S Package SOP-8L Identification Code AP1513 Package Information Package Type: SOP-8L ( in mm ) 3.70/4.10 5.79/6.20 0.08/0.25 0.254 0.38/1.27 Gauge Plane Seating Plane Detail "A" 7°~9° 1.30/1.50 1.75max. 0.20typ 7°~9° 0.35max. 45° Detail "A" 3.70/4.10 1.27typ 4.80/5.30 0.3/0.5 AP1513 Rev. 1 7 of 8 www.diodes.com JANUARY 2007 © Diodes Incorporated AP1513 PWM CONTROL 2A STEP-DOWN 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. AP1513 Rev. 1 8 of 8 www.diodes.com JANUARY 2007 © Diodes Incorporated