AP2008 PWM BUCK CONTROLLER General Description Features • • • • • • • • • • PWM Buck Control Circuitry Operating voltage can be up to 20V Under voltage Lockout (UVLO) Protection Short Circuit Protection (SCP) Soft-start circuit Variable Oscillator Frequency -- 300Khz Max 0.77V voltage reference Output 8-pin SOP package Lead Free Finish/ RoHS Compliant for Lead Free and “Green” products (Note 1) SOP-8L: Available in “Green” Molding Compound (No Br, Sb) The AP2008 integrates Pulse-Width-Modulation (PWM) control circuit into a single chip, mainly designs for power-supply regulator. All the functions include an on-chip 0.77V reference output, an error amplifier, an adjustable oscillator, a soft-start, UVLO, SCP circuitry, and a push-pull output circuit. Switching frequency is adjustable by trimming CT. During low VCC situation, the UVLO makes sure that the outputs are off until the internal circuit is operational normally. Applications • • • • Backlight inverter LCD Monitor XDROM, XDSL Product DC/DC converters in computers, etc. Ordering Information AP2008 X X X Package S: SOP-8L Device (Note 2) AP2008S Lead-Free L : Lead Free G : Green Package Packaging Code S SOP-8L Packing -U : Tube -13 : Taping Tube or Bulk Part Number Quantity Suffix 100 -U 13” Tape and Reel Part Number Quantity Suffix 2500/Tape & Reel Note: 1. RoHS revision 13.2.2003. Glass and High Temperature Solder Exemptions Applied, see EU Directive Annex Notes 5 and 7. 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. AP2008 Rev. 2 1 of 8 www.diodes.com DECEMBER 2006 © Diodes Incorporated -13 AP2008 PWM BUCK CONTROLLER Pin Descriptions Pin Assignments ( Top View ) OUT 1 VCC COMP FB 2 Name . 3 8 7 AP2008 6 4 5 GND CT SS SCP OUT PWM Output VCC Supply Voltage COMP FB SOP Description SCP Feedback Loop Compensation Voltage Feedback Short Circuit Protection SS Soft-Start. CT Timing Capacitor GND Ground Block Diagram VCC CT SS 10K-300KHz / CT value 0.77V Bandgap Reference 2.5V Internal use Oscillator UVLO VCC Iss PWM Amplifier FB + + - OUT Error Amplifier COMP 1.5V 0.7V + + SCP AP2008 Rev. 2 - 2 of 8 www.diodes.com GND DECEMBER 2006 © Diodes Incorporated AP2008 PWM BUCK CONTROLLER Absolute Maximum Ratings Symbol Rating Unit Supply voltage 22 V VI Amplifier input voltage 20 V VO Collector output voltage VCC-1.0V V Source current 200 mA ISINK Sink current 200 mA TOP Operating temperature range VCC ISOURCE TST Parameter Storage temperature range -20 to +85 o -65 to +150 o C C Recommended Operating Conditions Symbol Min. Max. Unit Supply voltage 3.6 20 V VI Amplifier input voltage 1.05 1.45 V VO Collector output voltage Vcc-1.5 V IFB Current into feedback terminal 45 µA RF Feedback resistor 100 CT Timing capacitor 100 6800 pF FOSC Oscillator frequency 10 300 KHz TOP Operating free-air temperature -20 85 ºC VCC AP2008 Rev. 2 Parameter 3 of 8 www.diodes.com kΩ DECEMBER 2006 © Diodes Incorporated AP2008 PWM BUCK CONTROLLER Electrical Characteristics (T =25ºC, V A Reference (REF) Symbol Parameter Comp connect to FB VREF Output voltage change with temperature Under voltage lockout (UVLO) Symbol Parameter VUT Upper threshold voltage (VCC) VLWT Lower threshold voltage (VCC) VHT Hysteresis (VCC) Short-circuit protection (SCP) control Symbol Parameter VIT Input threshold voltage VSTB Standby voltage VLT Latched input voltage ISCP Input (source) current Comparator threshold voltage VCT (COMP) Oscillator (OSC) Symbol Parameter FOSC Frequency Standard deviation of frequency ∆FOSC Frequency change with voltage Error-amplifier Symbol Parameter VIO Input offset voltage IIO Input offset current IIB Input bias current Common-mode input voltage VCM range Open-loop voltage AV amplification GBW Unity-gain bandwidth CMRR Common-mode rejection ratio VOH Max. output voltage VOL Min. output voltage IOI Output (sink) current (COMP) Output (source) current IOO (COMP) AP2008 Rev. 2 CC =6V, f=200 Khz) Conditions Min. 0.755 Typ. 0.770 -0.1 -0.2 Max. 0.785 ±1 ±1 Unit V % % Min. Typ. 2.9 2.4 500 Max. Unit V V mV Min. 0.60 100 Typ. 0.67 130 50 -15 Max. 0.75 160 100 -20 Unit V mV mV µA TA = -20ºC ~ 25ºC TA = 25ºC ~ 85ºC Conditions IO(REF) = 0.1mA TA = 25ºC Conditions TA = 25ºC No pull up No pull up VI = 0.7V, TA = 25ºC -10 1.5 Conditions CT =270 pF CT =270 pF VCC=3.6V ~ 20V Min. Conditions VO (FB)=0.77V VO (FB)=0.77V VO (FB)=0.77V Min. VCC=3.6V ~ 20V 1.05 RF=200 kΩ Typ. 200 10 1 Typ. 160 70 V Max. Unit KHz % Max. ±6 ±100 500 Unit mV nA nA 1.45 V 80 dB 1.5 80 VID = -0.1V, VO = 0.77V 0.5 1.6 MHz dB V V mA VID = 0.1V, VO = 0.77V -45 -70 µA 60 Vref-0.1 1 4 of 8 www.diodes.com DECEMBER 2006 © Diodes Incorporated AP2008 PWM BUCK CONTROLLER Electrical Characteristics (Continued) (T =25ºC, V A Output section Symbol ILEAK IDRV VSAT Parameter VT100 Total device Symbol ICCA Soft Start Symbol =6V, f=200 Khz) Conditions Min. Typ. Max. Unit 10 µA Leakage current VO = 20V Sink current VIN= 12V 200 mA Source current VIN= 12V 200 mA Output saturation voltage IO = 10 mA 1.0 VO = 6V 120 ISC Short-circuit output current PWM comparator Symbol Parameter VT0 CC Input threshold voltage at f = 10 KHz (COMP) Parameter Conditions CT=6800pF Maximum duty cycle Conditions Average supply current Min. Conditions V mA Typ. Max. Unit 0.6 0.7 V 1.2 1.3 Min. Typ. Max. Unit 6 10 mA Typ. Max. Unit CT = 270pF Parameter 1.5 Min. V VSS Soft-start Voltage 2.3 V ISS Constant Charge Current 20 µA Typical Application Circuit R3 30K Vcc = 12V C2 10nF (Optional) Q1 P mos 1 OUT GND 8 2 VCC CT 7 3 COMP SS 6 FB SCP 5 4 5A C1 470uF L1 10uH R1 1K Output 1V/5A C4 50nF (Optional) C3 470uF R2 4K C4 270pF C5 50nF C6 220nF Step-Down DC/DC converter AP2008 Rev. 2 5 of 8 www.diodes.com DECEMBER 2006 © Diodes Incorporated AP2008 PWM BUCK CONTROLLER Typical Characteristics AVERAGE SUPPLY CURRENT vs. POWER-SUPPLY VOLTAGE 0.785 0.78 0.775 0.77 0.765 0.76 0.755 5 Icc-Average Supply Current (mA) VrefReference Output Voltage (V) REFERENCE OUTPUT VOLTAGE vs. POWER-SUPPLY VOLTAGE 4 6 8 10 12 14 16 18 4 3 2 1 0 0 20 AVERAGE SUPPLY CURRENT vs. AMBIENT TEMPERATURE VCT (V) ICC - Average Supply Current (mA) 6 5 4 3 2 -25 0 25 50 75 0 100 tscp-SCP Time-out Period (ms) fosc - Frequency (KHz) 300 250 200 150 100 50 0 600 1100 1600 2100 2600 3100 3600 4100 4600 5100 5600 6100 6600 20 VCT(min) VCT(max) 100 200 300 SCP TIME-OUT PERIOD vs. SCP CAPACITANCE 35 30 25 20 15 10 5 0 45 90 135 180 225 270 315 360 405 450 495 Cscp - SCP Capacitance (nF) CT-Timing Capacitor (pF) AP2008 Rev. 2 16 Frequency (KHz) OSCILLATOR FREQUENCY vs. TIMING CAPACITANCE 100 12 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 TA - Ambient Temperature (℃) 350 8 VCT vs. FREQUENCY 7 -50 4 Vcc - Power-Supply Voltgae (V) Vcc-Power Supply Voltage (V) 6 of 8 www.diodes.com DECEMBER 2006 © Diodes Incorporated AP2008 PWM BUCK CONTROLLER Typical Characteristics (Continued) 30 SOFT-START TIME (Ts) vs. SOFT-START CAPACITOR (Css) Ts (mS) 25 20 15 10 5 0 25 50 75 100 125 150 175 200 Css (nF) Marking Information (1) SOP-8L (Top view) 5 8 Part Number Logo L : Lead Free G : Green AP2008 YY WW X X 1 4 Internal code Xth week: 01~52 Year: "01" =2001 "02" =2002 ~ AP2008 Rev. 2 7 of 8 www.diodes.com DECEMBER 2006 © Diodes Incorporated AP2008 PWM BUCK CONTROLLER Package Information ( unit in mm ) 0.08/0.25 0.254 5.79/6.20 3.70/4.10 SOP-8L Gauge Plane Seating Plane 0.38/1.27 Detail "A" 7°~9° 0.3/0.5 1.27typ 45° 0.20typ 1.75max. 1.30/1.50 0.35max. 7°~9° Detail "A" 3.70/4.10 4.80/5.30 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. AP2008 Rev. 2 8 of 8 www.diodes.com DECEMBER 2006 © Diodes Incorporated