L6917BDTR STMicroelectronics

L6917B 5 BIT PROGRAMMABLE DUAL-PHASE CONTROLLER 2 PHASE OPERATION WITH SYNCRHONOUS RECTIFIER CONTROL ULTRA FAST LOAD TRANSIENT RESPONSE INTEGRATED HIGH CURRENT GATE DRIVERS: UP TO 2A GATE CURRENT SO-28 TTL-COMPATIBLE 5 BIT PROGRAMMABLE ORDERING NUMBERS:L6917BD OUTPUT COMPLIANT WITH VRM 9.0 L6917BDTR (Tape & Reel) 0.8% INTERNAL REFERENCE ACCURACY 10% ACTIVE CURRENT SHARING ACCURACY DESCRIPTION DIGITAL 2048 STEP SOFT-START The device is a power supply controller specifically OVERVOLTAGE PROTECTION designed to provide a high performance DC/DC con- OVERCURRENT PROTECTION REALIZED version for high current microprocessors. USING THE LOWER MOSFET S R OR A dsON The device implements a dual-phase step-down con- SENSE RESISTOR troller with a 180 phase-shift between each phase. 300 kHz INTERNAL OSCILLATOR A precise 5-bit digital to analog converter (DAC) al- OSCILLATOR EXTERNALLY ADJUSTABLE lows adjusting the output voltage from 1.100V to UP TO 600kHz 1.850V with 25mV binary steps. POWER GOOD OUTPUT AND INHIBIT The high precision internal reference assures the se- FUNCTION lected output voltage to be within 0.8%. The high REMOTE SENSE BUFFER peak current gate drive affords to have fast switching PACKAGE: SO-28 to the external power mos providing low switching losses. APPLICATIONS The device assures a fast protection against load POWER SUPPLY FOR SERVERS AND over current and load over/under voltage. An internal WORKSTATIONS crowbar is provided turning on the low side mosfet if POWER SUPPLY FOR HIGH CURRENT an over-voltage is detected. In case of over-current, MICROPROCESSORS the system works in Constant Current mode. DISTRIBUTED DC-DC CONVERTERS BLOCK DIAGRAM ROSC / INH SGND VCCDR BOOT1 PGOOD UGATE1 HS 2 PHASE OSCILLATOR PWM1 PHASE1 - + CH 1 OVER LGATE1 CURRENT LS DIGITAL VCC SOFT START ISEN1 VCCDR LOGIC CURRENT PGNDS1 AND TOTAL READING + PROTECTIONS CURRENT PGND VID4 VID3 AVG PGNDS2 CURRENT CURRENT VID2 < > READING DAC VID1 CH2 OVER CURRENT VID0 ISEN2 CH1 OVER CURRENT CH 2 OVER LGATE2 LS CURRENT 10k + 10k IFB FBG PHASE2 - PWM2 10k ERROR FBR AMPLIFIER REMOTE UGATE2 BUFFER HS 10k Vcc BOOT2 VSEN FB COMP Vcc September 2002 1/33 Obsolete Product(s) - Obsolete Product(s) Obsolete Product(s) - Obsolete Product(s) CU RR EN T COR RECT ION CU RR EN T COR RECT ION LOGIC PWM LOGIC PWM ADAPTIVE ANTI ADAPTIVE ANTI CROSS-CONDUCTION CROSS-CONDUCTIONL6917B ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit Vcc, V to PGND 15 V CCDR V -V Boot Voltage 15 V BOOT PHASE V -V 15 V UGATE1 PHASE1 V -V UGATE2 PHASE2 LGATE1, PHASE1, LGATE2, PHASE2 to PGND -0.3 to Vcc+0.3 V All other pins to PGND -0.3 to 7 V Sustainable Peak Voltage t < 20ns 600kHz 26 V V phase THERMAL DATA Symbol Parameter Value Unit R Thermal Resistance Junction to Ambient 60 C/W th j-amb T Maximum junction temperature 150 C max T Storage temperature range -40 to 150 C storage T Junction Temperature Range -25 to 125 C j P Max power dissipation at T = 25C 2 W MAX amb PIN CONNECTION LGATE1 1 28 PGND VCCDR 2 27 LGATE2 PHASE1 3 26 PHASE2 UGATE1 4 25 UGATE2 BOOT1 5 24 BOOT2 VCC 6 23 PGOOD GND 7 22 VID4 COMP 8 21 VID3 FB 9 20 VID2 VSEN 10 19 VID1 FBR 11 18 VID0 FBG 12 17 OSC / INH / FAULT ISEN1 13 16 ISEN2 PGNDS1 14 15 PGNDS2 SO28 2/33 Obsolete Product(s) - Obsolete Product(s) Obsolete Product(s) - Obsolete Product(s)