ir3088a International Rectifier Corp., ir3088a Datasheet
ir3088a
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ir3088a Summary of contents
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... XPHASE DESCRIPTION The IR3088A Phase IC combined with an IR XPhase 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 IR3088A Order Quantity 3000 100 piece strips I I SOURCE SINK 1mA 1mA 1mA 1mA 1mA 1mA 1mA 30mA 5mA 5mA 1mA 1mA 1mA 1mA 1mA 20mA ...
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... Current Sense Amplifier output is an internal node. Slew rate at the ISHARE pin will be set by the internal 10kΩ resistor and any stray external capacitance Force I(PWMRMP) = 500µA. Measure V(PWMRMP) – V(DACIN) IR3088A ≤ 14V, 6V ≤ V ≤ 25V, 6V ≤ CCH MIN TYP ...
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... V(DACIN) (200mV overdrive) to GATEL transition to < 11V. Note 1. Compare to V(DACIN) I(PHSFLT) = 4mA V(PHSFLT) = 5.5V I(VRHOT) = 29mA V(VRHOT ≥ MIN ≥ 4.73mV 1.176V IR3088A MIN TYP MAX - -0.5 1 100 150 240 - -0 ...
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... Reference voltage input from the Control IC. 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 IR3088A MIN TYP MAX UNIT 2 5 ...
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... BIAS VOLTAGE PHASE TIMING CURRENT SHARE IR3088A PHASE IC PWM CONTROL 0.1uF VID VOLTAGE PHASE HOT CCS ADDITIONAL PHASES OC CONTROL BUS Figure 1. System Block Diagram IR3088A GATE VOLTAGE REGULATOR CIN COUT RCS RCS INPUT/OUTPUT 1/15 POWER GOOD PHASE FAULT VR HOT VOUT SENSE+ ...
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... REFERENCE BIASIN VOLTAGE RAMPIN+ + RPHS1 - RAMPIN- EAIN RPHS2 PWMRMP RPWMRMP SCOMP CPWMRMP SHARE CSCOMP ADJUST ERROR AMPLIFIER ISHARE 10K DACIN Figure 2. PWM Block Diagram IR3088A PHASE IC PWM LATCH GATEH CLOCK S PULSE PWM GENERATOR RESET COMPARATOR DOMINANT - R GATEL + ENABLE + BODY - BRAKING RAMP ...
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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 IR3088A 1/15 /05 ...
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... MAX MIN T SLEW + BODYDIODE IR3088A DUTY CYCLE DECREASE DUE TO LOAD DECREASE (BODY BRAKING) OR FAULT (VCC UV, VCCVID UV, OCP, VID=11111X the two time constants match, the L 1/15 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 IR3088A 1/15 /05 ...
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... IR3088A THEORY OF OPERATION Block Diagram The Block diagram of the IR3088A is shown in figure 6, and specific features are discussed in the following sections. RAMP COMPARATOR RMPIN+ CLOCK + PULSE RMPIN- - GENERATOR EAIN SYSTEM BIASIN REFERENCE VOLTAGE PWMRMP RAMP SLOPE ADJUST SCOMP SHARE ADJUST ERROR AMP ...
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... The most common failure mode of a buck converter is failure of the high side MOSFET. The IR3088A 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 its IR3088A current sense amplifier will be the DACIN voltage ...
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... IC VRHOT 5 ISHARE CSCOMP RBIASIN 20k 1 RMPIN+ IR3088A 2 RMPIN- 3 PHASE HOTSET 4 IC VRHOT 5 ISHARE CSCOMP RBIASIN 20k 1 RMPIN+ 2 IR3088A RMPIN- 3 PHASE HOTSET IC 4 VRHOT 5 ISHARE CSCOMP IR3088A POWERGOOD VRHOT PHASE FAULT RCS- CCS+ CCS- RCS+ DBST CBST CIN VOUT SENSE+ 15 VCCH 14 GATEH ...
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... DESIGN PROCEDURES - IR3081A AND IR3088A 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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... L _ The current sense amplifier gain of IR3088A decreases with temperature at the rate of 1470 ppm/°C, which compensates part of the inductor DCR increase. The phase IC die temperature is only a couple of degrees Celsius higher than the PCB temperature due to the low thermal impedance of MLPQ package. The minimum current sense ...
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... IR3088A 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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... RMPIN+ or RMPIN- between R PHASEx2, − ∗ ∗ PHASEx BIAS PHASEx 1 − BIAS HOTSET ∗ BIAS PHASEx 1 − BIAS HOTSET IR3088A (20) R and R PHASE1, PHASE2 PHASE3 and R and connect HOTSET pin PHASEx2, (21) (22) PHASEx and R PHASEx2 (23) (24) 1/15 /05 , connect . PHASEx3 ...
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... PWMRMP π ∗ IR3088A 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. 1/15 E /05 ...
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... V O ∗ DRP ∗ ∗ ∗ ∗ PWMRMP ∗ ∗ ∗ ∗ ∗ IR3088A (27) (28) (29) (30) (31) (32) (33) and capacitor C are not needed. Choose DRP (34) (35) (36) (37) (38) (39) 1/15 /05 and FB ...
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... V I PWMRMP Page and determine the C , C), SCOMP π ROOM LE CI π 6 ∗ ∗ PWMRMP SW PWMRMP − − DAC I DAC IR3088A ) based on the (40) (41) 1/15 /05 ...
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... DOWN =115 ºC = 7mΩ, Number Cn=10 C can be determined from the curve in Figure 13 of IR3081A Data OSC OSC − − − 6 − − 735 . − 115 = . − 6 IR3088A =30.1kΩ ms 1/15 /05 ...
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... R 3 ∗ TOFST − 3 ∗ ∗ Ω − 3 ∗ IR3088A VDAC OSC − 6 ∗ − = Ω 100 − 6 ∗ − 101 ∗ ∗ 400 * ...
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... Body Braking Related Resistors R N/A. The body braking during Dynamic VID is disabled. IR3088A EXTERNAL COMPONENTS PWM Ramp Resistor R and Capacitor C PWMRMP Set PWM ramp magnitude V PWMRMP resistor R , PWMRMP = R PWMRMP ∗ ∗ ∗ [ln PWMRMP . − ∗ ∗ ∗ ...
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... O CI − π − 4 π − ∗ ∗ 105 * . IR3088A . CP − 6 ∗ ∗ ∗ ∗ ( 560 365 Ω − − 560 * =68nF CP and calculate ...
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... Figure 13 of IR3081A Data OSC OSC − choose C =0.15uF . SS/DEL − − 6 − − 735 . − 115 = . − and Resistor R VDAC IR3088A =13.3kΩ ms VDAC OSC 1/15 =13.3kΩ) is /05 ...
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... O = − − 3 ∗ Ω 576 − 3 ∗ and R BBFB BBDRP IR3088A − 6 ∗ − = Ω 100 − 6 ∗ − 101 ∗ 800 * DRP =13.3kΩ. OSC − ...
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... IR3088A EXTERNAL COMPONENTS PWM Ramp Resistor R and Capacitor C PWMRMP Set PWM ramp magnitude V PWMRMP resistor R , PWMRMP = R PWMRMP [ln PWMRMP = − ∗ ∗ 12 800 * 10 100 * 10 Inductor Current Sensing Capacitor C Choose 47nF for capacitor C CS+, − − 100 ...
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... − 3 π 3500 * 22 − 4 π − ∗ ∗ 105 * . 3500 IR3088A = 146 kHz − − 6 ∗ ∗ ∗ 162 * . − and calculate SCOMP ...
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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 IR3088A , 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) • 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 IR3088A 1/15/ 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. • 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 IR3088A 1/15/ 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 IR3088A 1/15/ 05 ...
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... C/W, θ 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. IR3088A TAC Fax: (310) 252-7903 1/15/ 05 ...