AIC1567 5-bit DAC, Synchronous PWM Power Regulator with Linear Controller FEATURES DESCRIPTION Switching Regulator and Low Dropout Linear The AIC1567 is a high power, high efficiency Regulator on single chip. switching regulator controller optimized for high Simple Voltage-Mode PWM Control. performance microprocessor applications. It is Dual N-Channel MOSFET Synchronous Drive. designed to drive dual N-channel MOSFET in a Fast Transient Response. standard ±1.0% 5-Bit Digital-to-Analog Output Voltage. Featuring a low dropout linear regulator and a Adjustable Current Limit Without External Sense digitally programmable switching regulator, the Resistor. AIC1567 includes monitoring and protection Full 0% to 100% Duty Ratio. capabilities in addition to all the essential 200KHz Free-Running Oscillator Programmable synchronous PWM control functions. synchronous buck topology. up to 350KHz. Power-Good Output Voltage Monitor. The internal 5-bit Digital-to-Analog Converter Short Circuit Protection with Low Short Circuit (DAC) adjusts the output voltage from 2.0V to Output Current. 3.5V in 0.1V increments and 1.3V to 2.0V in 0.05V increments. The precision reference and voltage-mode control can provide output regulation within ±1.0% over temperature and APPLICATIONS line voltage shifts. Power Supply for Pentium II, Power PC and Alpha Microprocessors. The internal oscillator of the AIC1567 free-runs High-Power 5V to 3.xV DC/DC Regulators. at 200KHz and can be adjusted up to 350KHz. Low-Voltage Distributed Power Supplies. The resulting PWM duty ratio ranges from 0% to 100%. The error amplifier features a 11MHz bandwidth and 6V/µS slew rate, which enables high converter bandwidth for fast transient response. Analog Integrations Corporation 4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC DS-1567-00 TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw 1 AIC1567 ORDERING INFORMATION AIC1567 XX PIN CONFIGURATION ORDER NUMBER PACKAGE TYPE S: SMALL OUTLINE TOP VIEW AIC1567CS (PLASTIC SO) VSEN 1 TEMPERATURE RANGE C: 0°C~70°C 24 RT OCSET 2 23 OVP SS 3 22 VCC VID0 4 21 LGATE VID1 5 20 PGND VID2 6 19 BOOT VID3 7 18 UGATE VID4 8 17 PHASE COMP 9 16 PGOOD FB 10 15 GND CLP 11 14 LIDRI CLN 12 13 VLFB TYPICAL APPLICATION CIRCUIT 1000pF R2 12V C2 0.1µF C8 VID1 VID2 VID3 VID4 C7 33pF VID0 VID1 VID2 VID3 VID4 COMP FB CLP CLN RT OVP VCC M1 LGATE PGND BOOT UGATE PHASE PGOOD GND LIDRI VLFB C6 90.9K 1000pF C3 1000µF x 3 3µH M2 5V M3 FD3055 AIC1567 R6 + 5V VCORE L2 R1 R7 137 1% 237 1% VI/O 3.3V 10A + R5 3.01KΩ C1 1000µF R8 1.2M R4 15K D1 1N5820 VID0 L1 1µH NDP603AL 0.1µF VSEN OCSET SS C1 1µF RFP45N03L 2.2K + C4 1000µF x8 R3 47K C5 0.1µF Pentium II VCORE and VI/O DC/DC Converter 2 AIC1567 ABSOLUTE MAXIMUM RATINGS Supply Voltage, VCC ....…..................................……………........................................... 15V Boot Voltage, VBOOT ………...................……………...................................................... 15V Input, Output, or I/O Voltage .....…….........……………......…....... GND - 0.3V ESD Classification to VCC+0.3V ...........................…………......................……......................... 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: symbol θJA is measured with the component mounted on an evaluation PC board in free air. TEST CIRCUIT Refer to TYPICAL APPLICATION CIRCUIT. ELECTRICAL CHARACTERISTICS (VCC= 12V, Ta=25°°C, unless otherwise specified.) PARAMETER TEST CONDITIONS SYMBOL MIN. TYP. MAX. UNIT VCC Supply Current Nominal Supply UGATE Open IVCC 2 mA Power-On Reset VCC Threshold VOCSET=4.5V 7 Rising VOCSET Threshold 8.5 1.26 V V Oscillator Free Running Frequency RT Open 170 Total Variation 6KΩ< RT<200KΩ -20 Ramp Amplitude RT Open ∆VOSC 200 1.5 230 KHz +20 % VP-P 3 AIC1567 ELECTRICAL CHARACTERISTICS (Continued) PARAMETER TEST CONDITIONS SYMBOL MIN. TYP. MAX. UNIT +1.0 % Reference and DAC DACOUT Voltage Accuracy VDAC=1.8V ~3.5V -1.0 Error Amplifier DC Gain 76 dB GBW 11 MHz SR 6 V/µS Upper Gate Source RUGATE 8.0 12 Ω Upper Gate Sink RUGATE 5.5 10 Ω Lower Gate Source RLGATE 8.0 12 Ω Lower Gate Sink RLGATE 5.5 10 Ω 106 115 125 % IOCSET 170 200 230 µA IOVP 30 Gain-Bandwidth Product Slew Rate Gate Driver Protection Over-Voltage Trip (VSEN/DACOUT) OCSET Current Source VOCSET=4.5VDC OVP Sourcing Current VVSEN=5.5V, VOVP=0V Soft Start Current ISS Soft Start Sink Current under VVSEN =VDAC, VOCSET=5.0V, Current Limit VPHASE =0V, mA 10 µA 130 µA 65 mA VFB=VDAC=50mV Soft Start Sink Current under VVSEN =0, VOCSET=5.0V, Hard Current Limit VPHASE=0V, VFB=0V Power Good Upper Threshold (VVSEN /VDAC ) VVSEN Rising 106 114 % Lower Threshold (VVSEN / VDAC ) VVSEN Falling 84 94 % Hysteresis (VVSEN / VDAC ) Upper and Lower Threshold PGOOD Voltage Low IPGOOD=5mA VPGOOD 2 % 0.5 V Linear Regulator VLFB Feedback Voltage 1.18 VLFB Bias Current 1.21 1.24 40 LIDRI Sourcing Current 10 Current Limiting Threshold 10 V nA mA 20 30 mV 4 AIC1567 BLOCK DIAGRAM 115% POWER-ON RESET + VCC OVP 110% OVP + VSEN 90% + POWER GOOD PGOOD - OVER CURRENT + + - 50% OCSET 200µA 10µA SS 4V PHASE SOFT START BOOT UGATE VID0 VID1 VID2 VID3 VID4 VDAC 5BITS DAC - ERROR AMP VCC PWM COMPARATOR LGATE REFERENCE PGND OSCILLATOR FB RT COMP 1.2V LINEAR AMP. + CLP CLN GND CONTROL LOGIC + + + - - + 20mV - + - CURRENT SENSE LIDRI VLFB 5 AIC1567 PIN DESCRIPTIONS PIN 1: VSEN - Converter output voltage sense pin. Connect this pin to the converter output. The PGOOD and OVP comparator circuits use this signal to report output voltage status and for overvoltage protection function. PIN 2: 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 (IOCS), and the external MOSFET onresistance (RDS(ON)) jointly set the over current trip point according to the following equation: IPEAK = IOCS × ROCSET RDS( ON) If FB pin voltage is sensed to be below 50% of the internal voltage reference VDAC, the over current comparator cycles the soft-start function. PIN 3: SS PIN 4: VID0 PIN 5: VID1 PIN 6: VID2 PIN 7: VID3 PIN 8: VID4 - Soft start pin. Connect a capacitor from this pin to ground. An internal 10µA current source provides soft start function for the converter. - 5-bit DAC voltage select pin. TTL inputs used to set the internal voltage reference VDAC. When left open, these pins are internally pulled up to 5V and provide logic ones. The level of VDAC sets the converter output voltage as well as the PGOOD and OVP thresholds. Table 1 specifies the VDAC voltage for the 32 combinations of DAC inputs. PIN 9: COMP - External compensation pin. This pin is connected to error amplifier output and PWM comparator. An RC network is connected to FB pin to compensate the voltage-control feedback loop of the converter. PIN 10: FB - The error amplifier inverting input pin. The FB pin and COMP pin are used to compensate the voltage-control feedback loop. PIN 11: CLP - Linear regulator current sense pin. This pin is the positive input of the current sense comparator. PIN 12: CLN - Linear regulator current sense pin. This pin is the negative input of the current sense comparator. PIN 13: VLFB - Negative feedback pin for the linear regulator error amplifier. PIN 14: LIDRI - Linear regulator output drive pin. This pin can drive either a Darlington NPN or an N-channel MOSFET. PIN 15: GND - Signal GND. It also serves as the power GND for the upper gate driver. PIN 16: PGOOD-Power good indicator pin. PGOOD is an open drain output. This pin is pulled low when the converter output is ±10% out of the VDAC reference voltage. Table 1. Output Voltage Program VID4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 VID3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 VID2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 VID1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 VID0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 VDAC 3.5V 3.4V 3.3V 3.2V 3.1V 3.0V 2.9V 2.8V 2.7V 2.6V 2.5V 2.4V 2.3V 2.2V 6 AIC1567 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 to VCORE power by driving N-channel MOSFET, supply voltage of no higher than 12V is recommended since the negative power terminal of the internal driver is internally tied to GND. 2.1V 2.0V 2.05V 2.00V 1.95V 1.90V 1.85V 1.80V 1.75V 1.70V 1.65V 1.60V 1.55V 1.50V 1.45V 1.40V 1.35V 1.30V PIN 20: PGND - Driver power GND pin. PGND should be connected to a low impedance ground plane in close to lower NMOSFET source. PIN 21: LGATE - Lower N-MOSFET gate driver pin. PIN 17: PHASE - Over current detection pin. Connect the PHASE pin to source of the external MOSFET. This pin detects the voltage drop across the MOSFET RDS(ON) for over-current protection. PIN 22: VCC - The chip power supply pin. It also serves as power supply for LGATE driver. Recommended supply voltage is 12V. PIN 23: OVP -Over voltage indicator pin. This pin also provides a driver source current to turn on an external SCR in the event of an over voltage condition. PIN 24: RT - Frequency adjustment pin. Connecting a resistor (RT) from this pin to GND, increase the frequency by the following equation. PIN 18: UGATE- External MOSFET gate drive pin. Connect UGATE to gate of the external MOSFET. FS ≅ 200KHz + 5 × 10 5 log RT PIN 19: BOOT - External MOSFET driver power supply pin. To convert 5V main power PHYSICAL DIMENSIONS 24 LEAD PLASTIC SO (300 mil) (unit: mm) D E H e B A SYMBOL MIN MAX A 2.35 2.65 A1 0.10 0.30 B 0.33 0.51 C 0.23 0.32 D 15.20 15.60 E 7.40 7.60 e A1 C L 1.27(TYP) H 10.00 10.65 L 0.40 1.27 7