ir3086a International Rectifier Corp., ir3086a Datasheet
ir3086a
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ir3086a Summary of contents
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... PHASE IC WITH OVP, FAULT AND OVERTEMP DETECT DESCRIPTION The IR3086A Phase IC combined with an IR XPhase to implement power solutions for the latest high performance CPUs and ASICs. The “Control” IC provides overall system control and interfaces with any number of “Phase” ICs which each drive and monitor a single phase of a multiphase converter ...
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... DC, -2V for 100ns 0.3V -0.3V 27V -0.3V DC, -2V for 100ns 27V -0.3V 20V -0.3V 20V -0.3V 20V -0.3V 20V -0.3V 20V -0.3V IR3086A Order Quantity 3000 per reel 100 piece strips I I SOURCE SINK 1mA 1mA 1mA 1mA 1mA 1mA 1mA 30mA 5mA 5mA 1mA 1mA 1mA 1mA ...
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... Note 1 VCCH = 12V. Measure time from RMPIN input (50mV overdrive) to GATEL transition to <11V. V(RMPIN+) / V(BIASIN) or V(RMPIN-) / V(BIASIN) IR3086A ” 14V, 6V ” V ” 25V, 6V ” ” T ” ...
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... Compare to V(DACIN) VCCL = 12V. Measure time from CSIN > V(DACIN) (200mV overdrive) to GATEL transition to <11V. I(PHSFLT) = 4mA I(VRHOT) = 29mA V(VRHOT • MIN • 4.73mV 1.176V J IR3086A MIN TYP MAX - -0 150 -3.5 3 ...
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... Reference voltage input from the Control IC and inverting input to the OVP comparator. Current sensing and PWM operation referenced to this pin. 20 BIASIN System reference voltage for internal circuitry Page TEST CONDITION 6V ” V ” 14V CCH 14V ” V ” 25V CCH IR3086A MIN TYP MAX UNIT 2 5 ...
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... CURRENT SHARE IR3086A PHASE IC 0.1uF PHASE HOT CCS PHASE FAULT CURRENT SHARE IR3086A PHASE IC 0.1uF PHASE HOT CCS ADDITIONAL PHASES Figure 1. System Block Diagram IR3086A CIN COUT RCS RCS INPUT/OUTPUT 1/31 POWER GOOD PHASE FAULT VR HOT VOUT SENSE+ VOUT+ VOUT- VOUT SENSE- /05 ...
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... RPHS2 PWMRMP RPWMRMP SCOMP CPWMRMP SHARE CSCOMP ADJUST ERROR AMPLIFIER ISHARE 10K DACIN Figure 2. PWM Block Diagram connected between the VBIAS reference voltage and the Phase IC LGND pin. A IR3086A PHASE IC PWM LATCH GATEH CLOCK S PULSE PWM GENERATOR RESET COMPARATOR DOMINANT - R GATEL ...
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... PWM ramps are referenced to VDAC. Figure 4 depicts PWM operating waveforms under various conditions. Page 50% RAMP DUTY CYCLE SLOPE = 80mV / % DC SLOPE = 1.6mV / ns @ 200kHz SLOPE = 8.0mV / ns @ 1MHz CLK1 CLK2 CLK3 CLK4 CLK5 CLK6 CLK7 CLK8 Figure 3. 8 Phase Oscillator Waveforms IR3086A 1/31 /05 ...
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... MIN T SLEW BODYDIODE IR3086A DUTY CYCLE DECREASE DUE TO LOAD DECREASE (BODY BRAKING) OR FAULT (VCC UV, VCCVID UV, OCP, VID=11111X ” and is accomplished the two time constants match, the L 1/31 STEADY-STATE OPERATION /05 ...
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... PWM ramp thereby increasing its duty cycle and output current. The crossover frequency of the current share loop can be programmed with a capacitor at the SCOMP pin so that the share loop does not interact with the output voltage loop. Page Current Sense Amp CSOUT IR3086A 1/31 /05 ...
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... GATEH/GATEL voltage from rising due to leakage or other causes under these conditions. Over Voltage Protection (OVP) The IR3086A includes over-voltage protection that turns on the low side MOSFET to protect the load in the event of a shorted high-side MOSFET or connection of the converter output to an excessive output voltage. A comparator monitors the voltage at the CSIN- pin which is usually connected directly to the converter output ...
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... MOSFET. The IR3086A has the ability to detect if a phase stops switching and can provide this information to the system through the PHSFLT output pin phase stops switching its output current will drop to zero and the output of the current sense amplifier will be the DACIN voltage ...
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... CONTROL 18 VID1 VID2 VID2 VDRP VID3 6 16 VID3 IIN VID4 7 15 VID4 OCSET ROCSET ROSC Figure 7. IR3081A/IR3086A Six-Phase VRM/EVRD 10 Converter Page QGATE VGATE RBIASIN 20k DGATE 1 RMPIN+ 2 IR3086A RMPIN- 3 PHASE HOTSET 4 IC VRHOT 5 ISHARE CFB RBBFB RFB1 RFB ...
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... DESIGN PROCEDURES – IR3081A AND IR3086A CHIPSET IR3081A EXTERNAL COMPONENTS Oscillator Resistor Rosc The oscillator of IR3081A generates a triangle waveform to synchronize the phase ICs, and the switching frequency of the each phase converter equals the oscillator frequency, which is set by the external resistor R the curve in Figure 13 of IR3081A Data Sheet. ...
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... MAX CS _ MIN and R BBFB BBDRP are needed to restore the feedback voltage of the error amplifier after BBDRP and R are chosen to match R BBFB BBDRP IR3086A and room temperature L_MAX T )] (8) ROOM T )] (9) ROOM (10) LIMIT is the ratio of inductor peak current over ...
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... IR3086A EXTERNAL COMPONENTS PWM Ramp Resistor R and Capacitor C PWMRMP PWM ramp is generated by connecting the resistor R as the capacitor C between PWMRMP and LGND. Choose the desired PWM ramp magnitude V PWMRMP the capacitor C in the range of 100pF and 470pF, and then calculate the resistor R PWMRMP (15) ...
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... PHASEx PHASEx and connect RMPIN+ or RMPIN- between R PHASEx2 PHASEx BIAS PHASEx BIAS HOTSET BIAS PHASEx BIAS HOTSET IR3086A (20) R and R PHASE1, PHASE2 PHASE3 and R and connect HOTSET pin PHASEx2, (21) (22) PHASEx and R PHASEx2 (23) (24) 1/31 /05 , connect . PHASEx3 ...
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... C R PWMRMP DRP IR3086A and C removed. DRP CCP1 RFB RCP CCP CFB FB - EAOUT EAOUT VDAC RDRP + CDRP from Equations (25) and (26), where L CP (25) (26) is the equivalent resistance of inductor DCR. LE (27) 1/31 E /05 ...
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... C from Equations (32) and ( PWMRMP DRP PWMRMP IR3086A (28) (29) (30) (31) (32) (33) and capacitor C are not needed. Choose DRP (34) (35) (36) (37) (38) (39) 1/31 /05 and FB ...
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... PWM gain in the current share loop MI R PWMRMP PWMRMP Page and determine the C , C), SCOMP * ROOM 2 S PWMRMP SW PWMRMP DAC I DAC IR3086A ) based on the (40) ( 41) 1/31 /05 ...
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... Page =20 mV O_NLOFST =0-10mS VccPG =2.5mV/uS DOWN =115 ºC = 7mŸ, Number Cn=10 C can be determined from the curve in Figure 13 of IR3081A Data OSC OSC 735 . 115 . IR3086A =30.1kŸ ms 1/31 /05 ...
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... Adaptive Voltage Positioning Resistor TOFST . . IR3086A VDAC OSC ( 100 ( 101 400 * 10 ) DRP =30.1kŸ. OSC ...
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... R PHASE1 PHASE2 =0.246, RA =0.441 and RA PHASE4 PHASE5 = PHASE31 PHASE41 PHASE51 . 0 628 3 628 =3.24k , P PHASE42 PHASE52 IR3086A , and calculate the PWMRMP )] =16.2kŸ PWMRMP CS- , CS- PHASE1 =0.637 starting from down- PHASE6 = R =10kŸ, PHASE61 =7.87k , R =17.4k PHASE62 1/31 =0.628, /05 ...
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... ROOM 2 105 * . 2 IR3086A . 560 365 560 * =68nF CP and calculate SCOMP 011 . ...
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... DOWN =115 º Number Cn=62 C can be determined from the curve in Figure 13 of IR3081A Data OSC OSC choose C =0.15uF . SS/DEL 735 . 115 . and Resistor R VDAC IR3086A =13.3k ms VDAC OSC 1/31 =13. /05 ...
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... Adaptive Voltage Positioning Resistor n . 576 : and R BBFB BBDRP IR3086A ( 100 ( 101 800 * 10 ) DRP =13.3k . OSC 6 . ...
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... IR3086A EXTERNAL COMPONENTS PWM Ramp Resistor R and Capacitor C PWMRMP Set PWM ramp magnitude V PWMRMP resistor R , PWMRMP R PWMRMP [ln PWMRMP 800 * 10 100 * 10 Inductor Current Sensing Capacitor C Choose 47nF for capacitor C CS 100 * ...
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... ROOM 2 S 3500 * 105 * . 2 3500 IR3086A 146 kHz ( 62 ) 162 * . and calculate SCOMP 011 . ...
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... LGND LGND VCC VCC To Bottom To Bottom To Top To Top MOSFET MOSFET MOSFET MOSFET To To Switching Switching Node Node IR3086A , phase delay programming PWMRMP , and C ) close to phase IC. Use Kelvin CS- To LGND To LGND Plane Plane To Gate To Gate Drive Drive Voltage Voltage BIASIN BIASIN DACIN ...
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... Copper (• 0.1mm for 1 oz. Copper and • 0.23mm for 3 oz. Copper) x Four 0.3mm diameter vias shall be placed in the pad land spaced at 1.2mm, and connected to ground to minimize the noise effect on the IC, and to transfer heat to the PCB. Page IR3086A 1/31 /05 ...
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... Ensure that the solder resist in-between the lead lands and the pad land is • 0.15mm due to the high aspect ratio of the solder resist strip separating the lead lands from the pad land. x The 4 vias in the land pad should be tented with solder resist 0.4mm diameter, or 0.1mm larger than the diameter of the via. Page IR3086A 1/31 /05 ...
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... The maximum length and width of the land pad stencil aperture should be equal to the solder resist opening minus an annular 0.2mm pull back to decrease the incidence of shorting the center land to the lead lands when the part is pushed into the solder paste. Page IR3086A 1/31 /05 ...
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... C/ Data and specifications subject to change without notice. This product has been designed and qualified for the Consumer market. Qualification Standards can be found on IR’s Web site. Visit us at www.irf.com for sales contact information. IR3086A o C/W TAC Fax: (310) 252-7903 1/31 /05 ...