AIC1580/L Simple PWM Power Regulator with Shutdown FEATURES Operation Voltage up to 15V. Simple Voltage-Mode PWM Control. Fast Transient Response. DESCRIPTION The AIC1580 is a high-power, high-efficiency voltage-mode switching regulator controller for 2V and 1.3V ± 2% Feedback Voltage Reference Option. Adjustable Current Limit without External Sense Resistors. 200KHz Free-Running Oscillator. Short-Circuit Protection with Low Short Circuit Output Current. Low Shutdown Current Built-in Soft Start. motherboard VI/O power supply applications. Designed to drive a N-channel MOSFET in a standard buck topology, the AIC1580 features a high voltage CMOS output driver, short-circuit protection, and 8-pin package. An external 4-bit Digital-to-Analog Converter (DAC) can be used along with the AIC1580 to adjust the output voltage from 2.0V to 3.5V in 0.1V increments. Table 1 on the following page APPLICATIONS specifies the corresponding output voltage for Power Supply for Motherboard VGTL (1.5V Output) 16 combinations of DAC inputs as in the typical Power Supply for Motherboard VI/O. High-Power 5V to 3.xV DC/DC Regulators. Low-Voltage Distributed Power Supplies. application circuit. The 200KHz switching frequency allows for using small external components while maintaining high conversion efficiency. The 11MHz bandwidth and 6V/µS slew rate of the error amplifier ensures high converter bandwidth and fast transient response. The AIC1580 provides adjustable overcurrent and short-circuit protections by sensing the output current across the on resistance of the external N-channel MOSFET rather than an external low value sense resistor. The AIC1580L provides lower reference voltage (1.30V) than the default (2.00V, AIC1580) for lower VOUT requirement. Analog Integrations Corporation 4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC DS-1580-00 TEL: 886-3-5772500 Sep 5, 00 FAX: 886-3-5772510 www.analog.com.tw 1 AIC1580/L ORDERING INFORMATION AIC1580 XXX AIC1580CN AIC1580LCN (PLASTIC DIP) TEMPERATURE RANGE C=0°C~+70°C TOP VIEW 8 VCC OCSET 1 AIC1580CS AIC1580LCS (PLASTIC SO) REFERENCE VOLTAGE DEFAULT: 2.00V L: 1.30V PIN CONFIGURATION ORDER NUMBER PACKAGE TYPE N: PLASTIC DIP S: SMALL OUTLINE SD 2 7 UGATE COMP 3 6 PHASE FB* 4 5 GND *AIC1580: 2.00V AIC1580L: 1.30V TYPICAL APPLICATION CIRCUIT C9 *C1 MUST BE VERY CLOSE TO VCC PIN R1 C1 1000P 10 12V 1U R2 5V L1 2.2K 1.5U AIC1580 M1 CLSET VCC SD UDRI COMPPHASE FB GND C7 IR3303 C6 R6 33P 90.9K + C3 3000UF R9 L2 5K 7U D1 SRA1620 1000P VOUT + C4 6000UF R7 VID0 6.04K VID1 30.1K VID2 15.0K R8 R4 R5 3.01K R3 VID3 7.5K Switching Regulator for Pentium VCORE Supply 2 AIC1580/L Table 1. Output Voltage Program VID3 VID2 1 1 1 1 1 1 1 1 1 0 1 0 1 0 1 0 0 1 0 1 0 1 0 1 0 0 0 0 0 0 0 0 VID1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 VID0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 VOUT 2.00V 2.10V 2.20V 2.30V 2.40V 2.50V 2.60V 2.70V 2.80V 2.90V 3.00V 3.10V 3.20V 3.30V 3.40V 3.50V ABSOLUTE MAXIMUM RATINGS Supply Voltage, VCC ....…...………............................…………......................................... 15V Input, Output, or I/O Voltage ...............………………....……......... GND - 0.3V to VCC+0.3V ESD Classification .............................………….....……..............……......................... Class 2 Recommended Operating Conditions Supply Voltage, VCC ....…......................………….......……….................................. 12V ±10% Ambient Temperature Range .…................................………….……….................. 0°C~70°C Junction Temperature Range ....…............……….........…..……......................... 0°C~ 100°C Thermal Information Thermal Resistance, θJA (Typical, Note 1) SOIC Package ...............................………………………..……………........…. 100°C/W SOIC Package (with 3 in2 of Copper) ……………………………………......….. 90°C/W Maximum Junction Temperature (Plastic Package) ……….……..………................... 150°C Maximum Storage Temperature Range …………..…………......…….…......... –65°C~150°C Maximum Lead Temperature (Soldering 10 Sec) …………………...……......…......... 300°C Note 1: θJA is measured with the component mounted on an evaluation PC board in free air. TEST CIRCUIT Refer to TYPICAL APPLICATION CIRCUIT. 3 AIC1580/L ELECTRICAL CHARACTERISTICS specified.) PARAMETER TEST CONDITIONS (VCC= 12V, Ta=25°°C, unless otherwise SYMBOL MIN. TYP. MAX. UNIT VCC Supply Current Nominal Supply UGATE Open IVCC 2 mA 9.5 V Frequency 200 KHz Duty Cycle 88 % Power-On Reset VCC Threshold VOCSET=4.5V Oscillator Internal Reference Voltage Reference Voltage AIC1580 AIC1580L 1.96 1.27 2.00 1.30 2.04 1.33 V Error Amplifier DC Gain 76 dB GBW 11 MHz SR 6 V/µS Upper Gate Source RUGATE 7 Ω Upper Gate Sink RUGATE 5 Ω IOCSET 200 µA ISS 10 µA Gain-Bandwidth Product Slew Rate Comp=10pF Gate Driver Protection OCSET Current Source SS Current VOCSET =4.5VDC Shutdown Shutdown Low Input VINL Shutdown High Input VINH Shutdown Mode Current 0.35 2 V V 1 µA 4 AIC1580/L TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs. Load Current OCSET Current vs. Temperature 100 Vo=1.3V 90 80 200 Vo=2.0V Clset (µA) Efficiency (%) 70 Vo=3.5V 60 50 198 Tc=134ppm/ C@ 0~100°C 196 194 40 192 30 1 2 3 4 5 6 IOUT (A) 7 8 Over-Current Operation 9 10 11 -40 -20 0 20 40 60 80 100 Temperature (°C) 120 140 160 Output Clamped by Built-In Soft Start Transient Response 5 AIC1580/L BLOCK DIAGRAM Over Current - PHASE + SD OCSET 200µA Power-On Reset Built-In Soft Start REF + Error AMP VCC PWM Comparator + Gate Control - UGATE FB GND COMP Oscilator PIN DESCRIPTIONS PIN 1: OCSET - Current limit sense pin. Connect a resistor ROCSET from this pin to the drain of the external MOSFET. ROCSET, an internal 200µA current source (IOCSET), and the external MOSFET onresistance (RDS(ON)) jointly set the overcurrent trip point according to the following equation: IPEAK = PIN 4: FB - The error amplifier inverting input pin. The FB pin and COMP pin are used to compensate the voltage-control feedback loop. PIN 5: GND- Ground pin. PIN 6: PHASE- Overcurrent detection pin. Connect the PHASE pin to source of the external NMOSFET. This pin detects the voltage drop across the MOSFET RDS(ON) for overcurrent protection. IOCSET × ROCSET RDS(ON) If FB pin voltage is sensed to be below 50% of the internal voltage reference VDAC, the overcurrent comparator cycles the soft-start function. PIN 2: SD connected to FB pin to compensate the voltage-control feedback loop of the converter. - Shutdown pin. Connect this pin to ground for shutdown. PIN 3: COMP - External compensation pin. This pin is connected to error amplifier output and PWM comparator. A RC network is PIN 7: UGATE- External MOSFET gate drive pin. Connect this pin to gate of the external MOSFET. PIN 8: VCC -The chip power supply pin. Recommended supply voltage is 12V. 6 AIC1580/L APPLICATION CIRCUIT C9 R1 1000P CLSET SD 33P C7 R6 PHASE R9 GND 3000µF L2 R5 13K 2K VOUT 7µF D1 SRA1620 R7 C3 IR3303 5K 1000P 5V 1.5µF M1 AIC1580 C6 90.9K 1.5V/10A + C4 6000µF PHYSICAL DIMENSIONS 8 LEAD PLASTIC SO (unit: mm) D H E e C B SYMBOL MIN MAX A 1.35 1.75 A1 0.10 0.25 B 0.33 0.51 C 0.19 0.25 D 4.80 5.00 E 3.80 4.00 e A A1 FB L1 + VCC UDRI COMP 12V *C1 must be very close to VCC PIN 2.2K R2 10 *C1 1µF 1.27(TYP) H 5.80 6.20 L 0.40 1.27 L 7 AIC1580/L 8 LEAD PLASTIC DIP (unit: mm) D E1 E A2 A1 C L eB b e SYMBOL MIN MAX A1 0.381 — A2 2.92 4.96 b 0.35 0.56 C 0.20 0.36 D 9.01 10.16 E 7.62 8.26 E1 6.09 7.12 e 2.54 (TYP) eB — 10.92 L 2.92 3.81 8