AP1635 PWM/PFM DUAL MODE STEP-DOWN DC/DC CONVERTER General Description Features • • • • • • Input voltage range: 2.2V~5V (VOUT type) Oscillator frequency: 700KHz (Typ.) Internal reference: 1.0V (Typ.) High efficiency: 93% (Typ.) Current limit and thermal shutdown protection Pb-Free Package: SOP-8L The AP1635 series are multi-functional step-down DC/DC converters with built-in speed, low ON resistance drivers. It is capable to deliver more than 1.2A output current with external coil, diode and capacitor. Output voltage is set-up by the external resistors. (±2.5% accuracy). The 700KHz AP1635 that can work out with small value external components comes out more compact board. The device switches to and works under PFM mode with light loads. It keeps at high efficiency for both light loads and large output current. AP1635 can be soft-start with a proper capacitor connected between CE/SS pin and ground. The stand-by current is less than 6uA when CE/SS pin is at “LOW” status. The device is forced to switch off as the voltage at that pin is lower than the stipulated voltage. Pin Assignments Pin Descriptions ( Top View ) 1 8 GND CE/SS 2 7 GND SVcc 3 PVcc 4 FB AP1635 Pin Name Pin No. FB 1 CE/SS 6 SW 5 SW SVcc PVcc SW GND Description Feedback pin Chip Enable/ Soft Start: 2 H: Enable L: Disable IC signal power supply pin, add a 3 20Ω resistor to PVcc and a 0.1µF capacitor to GND. 4 IC power supply pin Switch Pin. Connect external 5/6 inductor/diode here. Minimize trace area at this pin to reduce EMI. 7/8 GND Pin Applications • • • • • Electronic Information Organizers Palmtops Cellular and portable phones Portable Audio Systems Various Multi-function Power Supplies AP1635 Rev. 3 1 of 7 www.diodes.com OCTOBER 2006 © Diodes Incorporated AP1635 PWM/PFM DUAL MODE STEP-DOWN DC/DC CONVERTER Ordering Information AP 1635 X X X Package S: SOP-8L Device AP1635S Package Packaging Code S SOP-8L Lead Free L : Lead Free Packing -U : Tube -13 : Taping Tube or Bulk -13” Tape and Reel Part Number Quantity Part Number Quantity Suffix Suffix 2500/Tape & Reel -13 ⎯ ⎯ Block Diagram SVcc FB + - AP1635 Rev. 3 Vref with CE Current Limit + ERR AMP SW Soft Start CE/SS PVcc Phase Compensation PWM/PFM Controller 2 of 7 www.diodes.com - PWM Comparator Ramp Wave Generator, OSC GND OCTOBER 2006 © Diodes Incorporated AP1635 PWM/PFM DUAL MODE STEP-DOWN DC/DC CONVERTER Absolute Maximum Ratings Symbol Parameter Ta=25°C Units Ratings VCC/SVCC VSW VFB VCE/SS VIN Pin Voltage SW Pin Voltage FB Pin Voltage CE/SS Pin Voltage -0.3 ~ 5.0 -0.3 ~ VIN+0.3 -0.3 ~ VIN+0.3 -0.3 ~ VIN+0.3 V V V V Pd Continuous Total Power Dissipation Internal limited Topr Operating Ambient Temperature -25 ~ +80 °C Tstg Storage Temperature -40 ~ +125 °C Electrical Characteristics VIN=5V, VOUT＝2V, Load=300mA, Ta=25°C Sym. VFB VIN Parameter Conditions FB Input Voltage Line Regulation Load Regulation UVLO Voltage（min. operating voltage） Operating Current VIN=2.2~5V, Load=10mA IOUT=10~1200mA VCC, voltage required to maintain H at VUVLO VOUT ICC CE/SS=VIN, No Load No external components, ICCQ Supply Current CE/SS=VIN, VFB=1.2V No external components, ISTB Stand-by Current CE/SS=0V, VFB=0V peak current ICL Current Limit VIN=5V, VOUT=2V Fosc Oscillator Frequency Load=300mA, VIN=5V, VOUT=2V MAXDTY Maximum Duty Ratio PFMDTY PFM Duty Ratio No load Apply 1.4V (min.) to CE/SS, determine VCEH CE/SS ”High” Voltage VOUT ”High” VCEL CE/SS ”Low” Voltage Same as VCEH, determine VOUT/”Low” EFFI Efficiency VCC=5V, VOUT=3.3V, Load=300mA Rdson Rdson Condition IOUT=300mA, VIN=5V, VOUT=2V AP1635 Rev. 3 3 of 7 www.diodes.com Min. 0.975 2.2 - Typ. 1.0 - Max. 1.025 5 0.12 1.2 Units V V % % - - 2 V - 100 150 µA - 90 120 µA - 6 - µA 1200 1400 1600 mA 500 85 15 700 90 25 35 kHz % % 1.4 - - V - 93 350 0.6 450 V % mΩ OCTOBER 2006 © Diodes Incorporated AP1635 PWM/PFM DUAL MODE STEP-DOWN DC/DC CONVERTER Typical Performance Characteristics Vcc v.s. Operating Current 200 Vcc v.s. Quiescent Current 200 Icc (uA) 180 180 Quiescent Current (uA) Operating Current (uA) 160 140 120 100 80 60 40 20 160 140 120 100 0 80 60 40 20 0 2.5 3 3.5 4 4.5 2.5 5 3 3.5 Vcc v.s. Stand-by Current 4.5 5 Vcc v.s. Frequency 8 800 7.5 780 760 7 Frequency (KHz) Stand-by Current (uA) 4 Vcc (V) Vcc (V) 6.5 6 5.5 5 4.5 740 720 700 680 660 640 620 4 600 2.5 3 3.5 Vcc (V) 4 4.5 5 Vcc v.s. Current Limit AP1635 Rev. 3 2.5 3 3.5 Vcc (V) 4 4.5 5 Vcc v.s. RDS(ON) 4 of 7 www.diodes.com OCTOBER 2006 © Diodes Incorporated AP1635 PWM/PFM DUAL MODE STEP-DOWN DC/DC CONVERTER 1.4 600 1.3 500 1.1 RDS(ON) (mΩ) Current Limit (A) 1.2 Current Limit 1 0.9 0.8 0.7 400 300 200 100 0.6 Vout=2V 0 0.5 3 3.5 4 4.5 2.5 5 3 3.5 Vcc (V) Vcc (V) 4 4.5 5 Typical Performance Characteristics (Continued) Load Regulation 0.3 3 0.2 2 0.1 1 V / VOUT (%) V / VOUT (%) Line Regulation 0.0 -0.1 0 -1 -0.2 -2 -0.3 -3 2.5 3 3.5 4 4.5 5 0 Vcc (V) 200 400 600 Load (mA) 800 1000 1200 Typical Application Circuit 2.2V ~ 5.5V V IN PVcc 20Ω 68u 1MΩ AP1635 SVcc CE/SS GND 10uH SW VOUT B240A R2 FB R1 0.1uF 0.1uF 68uF 1nF Vout = 1 × (1 + R2 ) R1 R1=100K ~ 200K AP1635 Rev. 3 5 of 7 www.diodes.com OCTOBER 2006 © Diodes Incorporated AP1635 PWM/PFM DUAL MODE STEP-DOWN DC/DC CONVERTER Marking Information ( Top View ) 8 5 Logo Part no. AP1635 YY WW X 4 ~ 1 ID code: internal Xth week: 01~52 Year: "01" =2001 "02" =2002 SOP-8L Package Information 0.254 0.08/0.25 5.79/6.20 3.70/4.10 Package Type: SOP-8L Gauge Plane Seating Plane 0.38/1.27 Detail "A" 7°~9° 0.20typ 1.30/1.50 1.75max. 0.35max. 45° 0.3/0.5 1.27typ 7°~9° Detail "A" 3.70/4.10 4.80/5.30 AP1635 Rev. 3 6 of 7 www.diodes.com OCTOBER 2006 © Diodes Incorporated AP1635 PWM/PFM DUAL MODE STEP-DOWN DC/DC 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. AP1635 Rev. 3 7 of 7 www.diodes.com OCTOBER 2006 © Diodes Incorporated