AP2004 PWM Buck Controller Features General Description - PWM Buck Control Circuitry - Operating voltage can be up to 27V - Under voltage Lockout (UVLO) Protection - Short Circuit Protection (SCP) - Soft-start circuit - Variable Oscillator Frequency -- 300Khz Max - 1.25V voltage reference Output - 8-pin PDIP and SOP packages The AP2004 integrates Pulse-Width-Modulation (PWM) control circuit into a single chip, mainly designs for power-supply regulator. All the functions include an on-chip 1.25V 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 operates normally. Applications - Backlight inverter - LCD Monitor - XDROM, XDSL Product - DC/DC converters in computers, etc. Pin Assignment Pin Descriptions ( Top View ) Name OUT 1 8 VCC COMP FB 2 7 3 6 4 5 GND CT SS SCP CT Timing Capacitor FB Voltage Feedback SS Soft-Start. COMP PDIP/SOP Description Feedback Loop Compensation OUT PWM Output GND Ground VCC Supply Voltage SCP Short Circuit Protection Ordering Information AP2004 X Package N: PDIP-8L S: SOP-8L X X Lead Free Packing Blank : Tube Blank : Normal L : Lead Free Package A : Taping 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. 0.4 Arpr 6, 2004 1/8 AP2004 PWM Buck Controller Block Diagram VCC 1.25V Bandgap Reference CT SS 2.5V Internal use Oscillator UVLO VCC MAX.500KHz Iss PWM Amplifier FB + + - OUT Error Amplifier COMP 0.7V 1.5V + + SCP GND Absolute Maximum Ratings Symbol Rating Unit Supply voltage 28 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 TLEAD Parameter Storage temperature range Lead temperature 1.6 mm(1/16 inch) from case for 10 seconds Anachip Corp. www.anachip.com.tw -20 to +85 o C -65 to +150 o C 260 o C Rev. 0.4 Apr 6, 2004 2/8 AP2004 PWM Buck Controller Recommended Operating Conditions Symbol Min. Max. Unit Supply voltage 3.6 27 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 VCC Parameter kΩ FOSC Oscillator frequency 10 300 KHz TOP Operating free-air temperature -20 85 ºC 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 =6V, f=200 Khz) CC Conditions Min. 1.225 Typ. 1.25 -0.1 -0.2 Max. 1.275 ±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 Anachip Corp. www.anachip.com.tw Min. Typ. 200 10 1 V Max. Unit KHz % Rev. 0.4 Apr 6, 2004 3/8 AP2004 PWM Buck Controller Electrical Characteristics (Continued) (T =25ºC, V A 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) Output section Symbol Parameter ILEAK IDRV VSAT VT100 Total device Symbol ICCA Soft Start Symbol Conditions VO (FB)=1.25V VO (FB)=1.25V VO (FB)=1.25V Min. VCC=3.6V ~ 20V 1.05 RF=200 kΩ Typ. 160 70 Max. ±6 ±100 500 Unit mV nA nA 1.45 V 80 dB 1.5 80 VID = -0.1V, VO = 1.25V 0.5 1.6 MHz dB V V mA VID = 0.1V, VO = 1.25V -45 -70 µA Min. Typ. 60 Vref-0.1 1 Conditions Max. Unit 10 µA Leakage current VO = 25V Sink current VIN= 20V 200 mA Source current VIN= 20V 200 mA Output saturation voltage IO = 10 mA 1.0 VO = 6V 120 ISC Short-circuit output current PWM comparator Symbol Parameter VT0 =6V, f=200 Khz) CC Input threshold voltage at f = 10 KHz (COMP) Conditions CT Maximum duty cycle Parameter Average supply current Min. Conditions 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 Anachip Corp. www.anachip.com.tw Rev. 0.4 Apr 6, 2004 4/8 AP2004 PWM Buck Controller Typical Application Circuit R3 10K~100K Vcc = 12V C2 10nF Optional Q1 C1 470uF P mos 1 OUT GND 8 2 VCC CT 7 COMP SS 6 FB SCP 5 3 4 L1 33uH Output C4 50nF Optional R1 9K 5A C3 470uF R2 3K C4 270pF C5 50nF C6 220nF Step-Down DC/DC converter Typical Characteristics AVERAGE SUPPLY CURRENT v.s. POWER-SUPPLY VOLTAGE 1.26 1.255 1.25 1.245 1.24 1.235 1.23 1.225 1.22 5 Icc-Average Supply Current (mA) VrefReference Output Voltage (V) REFERENCE OUTPUT VOLTAGE v.s. POWER-SUPPLY VOLTAGE 4 8 12 16 20 24 28 4 3 2 1 0 0 Vcc-Power Supply Voltage (V) AVERAGE SUPPLY CURRENT v.s. AMBIENT TEMPERATRUE VCT (V) ICC - Average Supply Current (mA) 6 5 4 3 2 -25 0 25 50 75 8 12 16 20 24 28 VCT(min) VCT v.s. Frequency 7 -50 4 Vcc - Power-Supply Voltgae (V) 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 0 100 VCT(max) 100 200 300 Frequency (KHz) TA - Ambient Temperatrure(℃) Anachip Corp. www.anachip.com.tw Rev. 0.4 Apr 6, 2004 5/8 AP2004 PWM Buck Controller Typical Characteristics (Continued) OSCILLATOR FREQUENCY v.s. TIMING CAPACITANCE tscp-SCP Time-out Period (ms) fosc - Frequency (KHz) 350 300 250 200 150 100 50 0 100 600 SCP TIME-OUT PERIOD v.s. SCP CAPACITANCE 35 30 25 20 15 10 5 0 45 1100 1600 2100 2600 3100 3600 4100 4600 5100 5600 6100 6600 90 135 180 225 270 315 360 405 450 495 Cscp - SCP Capacitance (nF) CT-Timing Capacitor (pF) SOFT-START TIME (Ts) v.s. SOFT-START CAPACITOR (Css) 30 Ts (mS) 25 20 15 10 5 0 25 50 75 100 125 150 175 200 Css (nF) Marking Information (Top View) 8 Logo Part No. 5 ID code Blank: normal L: Lead Free Package Xth week: 01~52 Year: "01" =2001 "02" =2002 AC AP2004 YY WW X X 1 4 ~ PDIP/SOP Anachip Corp. www.anachip.com.tw Rev. 0.4 Apr 6, 2004 6/8 AP2004 PWM Buck Controller Package Information (1) PDIP-8L (Plastic Dual-in-line Package ) D E1 E-PIN O0.118 inch E 15 (4X) PIN #1 INDENT O0.025 DEEP 0.006-0.008 inch C 7 (4X) A1 L A A2 eB B S Symbol A A1 A2 B B1 B2 C D E E1 e L eB S e B1 B2 Dimensions in millimeters Min. Nom. Max. 5.33 0.38 3.1 3.30 3.5 0.36 0.46 0.56 1.4 1.52 1.65 0.81 0.99 1.14 0.20 0.25 0.36 9.02 9.27 9.53 7.62 7.94 8.26 6.15 6.35 6.55 2.54 2.92 3.3 3.81 8.38 8.89 9.40 0.71 0.84 0.97 Anachip Corp. www.anachip.com.tw Dimensions in inches Min. Nom. Max. 0.210 0.015 0.122 0.130 0.138 0.014 0.018 0.022 0.055 0.060 0.065 0.032 0.039 0.045 0.008 0.010 0.014 0.355 0.365 0.375 0.300 0.313 0.325 0.242 0.250 0.258 0.100 0.115 0.130 0.150 0.330 0.350 0.370 0.028 0.033 0.038 Rev. 0.4 Apr 6, 2004 7/8 AP2004 PWM Buck Controller Package Information (Continued) H E (2) SOP- 8L(JEDEC Small Outline Package) L VIEW "A" D 0.015x45 7 (4X) e B A1 C A A2 7 (4X) VIEW "A" y Symbol A A1 A2 B C D E e H L y θ Dimensions In Millimeters Min. Nom. Max. 1.40 1.60 1.75 0.10 0.25 1.30 1.45 1.50 0.33 0.41 0.51 0.19 0.20 0.25 4.80 5.05 5.30 3.70 3.90 4.10 1.27 5.79 5.99 6.20 0.38 0.71 1.27 0.10 0O 8O Anachip Corp. www.anachip.com.tw Dimensions In Inches Min. Nom. Max. 0.055 0.063 0.069 0.040 0.100 0.051 0.057 0.059 0.013 0.016 0.020 0.0075 0.008 0.010 0.189 0.199 0.209 0.146 0.154 0.161 0.050 0.228 0.236 0.244 0.015 0.028 0.050 0.004 0O 8O Rev. 0.4 Apr 6, 2004 8/8