IR3081M International Rectifier, IR3081M Datasheet

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DESIGNS. REPLACE WITH IR3081A DESCRIPTION The IR3081 Control IC combined with an IR XPhase to implement a complete VR 10 power solution. The “Control” IC provides overall system control and interfaces with any number of “Phase ICs” which each drive ...

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... ORDERING INFORAMATION Device IR3081MTR * IR3081M * Samples only ABSOLUTE MAXIMUM RATINGS Operating Junction Temperature……………..150 Storage Temperature Range………………….-65 ESD Rating………………………………………HBM Class 1C JEDEC standard ...

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ELECTRICAL SPECIFICATIONS Unless otherwise specified, these specifications apply over: 9.5V ≤ V PARAMETER VDAC Reference System Set-Point Accuracy Source Current Sink Current VID Input Threshold VID Input Bias Current Regulation Detect Comparator Input Offset Regulation Detect to EAOUT Delay BBFB ...

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PARAMETER Oscillator Switching Frequency Peak Voltage (5V typical, measured VBIAS) Valley Voltage (1V typical, measured VBIAS) VBIAS Regulator Output Voltage Current Limit Soft Start and Delay SS/DEL to FB Input Offset Voltage Charge Current ...

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PIN DESCRIPTION PIN# PIN SYMBOL PIN DESCRIPTION 1 OSCDS Apply a voltage greater than VBIAS to disable the oscillator. Used during factory testing & trimming. Ground or leave open for normal operation. 2-7 VID0-5 Inputs to VID ...

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SYSTEM THEORY OF OPERATION TM XPhase Architecture TM The XPhase architecture is designed for multiphase interleaved buck converters which are used in applications requiring small size, design flexibility, low voltage, high current and fast transient response. The architecture can control ...

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PWM Control Method The PWM block diagram of the XPhase trailing edge modulation is used. A high-gain wide-bandwidth voltage type error amplifier in the Control IC is used for the voltage control loop. An external RC circuit connected to the ...

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VPEAK (5.0V) VPHASE4&5 (4.5V) VPHASE3&6 (3.5V) VPHASE2&7 (2.5V) VPHASE1&8 (1.5V) VVALLEY (1.00V) PWM Operation The PWM comparator is located in the Phase IC. Upon receiving a clock pulse, the PWM latch is set; the PWMRMP voltage begins to increase; the ...

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PHASE IC CLOCK PULSE EAIN PWMRMP VDAC GATEH GATEL STEADY-STATE OPERATION TM Body Braking In a conventional synchronous buck converter, the minimum time required to reduce the current in the inductor in response to a load step decrease is; The ...

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Figure 5. Inductor Current Sensing and Current Sense Amplifier The advantage of sensing the inductor current versus high side or low side sensing is that actual output current being delivered to the load is obtained rather than peak or sampled ...

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IR3081 THEORY OF OPERATION Block Diagram The Block diagram of the IR3081 is shown in Figure 6, and specific features are discussed in the following sections. VCC - START + STOP + VCC UVLO 9.1V COMPARATOR 8.9V - ENABLE ENABLE ...

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The IR3081 can accept changes in the VID code while operating and vary the DAC voltage accordingly. The sink/source capability of the VDAC buffer amplifier is programmed by the same external resistor that sets the oscillator frequency. The slew rate ...

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Processor Pins (0 = low high) VID4 VID3 VID2 VID1 ...

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Control IC VDAC Inductor DCR Temperature Correction If the thermal compensation of the inductor DCR provided by the temperature dependent gain of the current sense amplifier is not adequate, a negative temperature coefficient (NTC) thermistor can be used for additional ...

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Soft Start, Over-Current Fault Delay, and Hiccup Mode The IR3081 has a programmable soft-start function to limit the surge current during the converter start-up. A capacitor connected between the SS/DEL and LGND pins controls soft start as well as over-current ...

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VCC (12V) ENABLE 3.91V SS/DEL 1.3V VOUT PWRGD IOUT START-UP NORMAL OPERATION (ENABLE GATES (VOUT CHANGES DUE TO LOAD FAULT MODE) AND VID CHANGES) Power Good Output The PWRGD pin is an open-collector output and should be pulled up to ...

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APPLICATION INFORMATION 12V RVCC 10 ohm CVCC 0.1uF 1nF 0.1uF ENABLE 1 OSCDS VBIAS 2 VID5 VID5 BBFB IR3081 VID0 3 VID0 EAOUT CONTROL VID1 4 VID1 FB IC VID2 5 VID2 VDRP VID3 6 VID3 IIN VID4 7 VID4 ...

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DESIGN PROCEDURES - IR3081 AND IR3086 CHIPSET IR3081 EXTERNAL COMPONENTS Oscillator Resistor Rosc The oscillator of IR3081 generates a triangle waveform to synchronize the phase ICs, and the switching frequency of the each phase converter equals the oscillator frequency, which ...

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VDAC down-slope and is given by Equation (9), where I shown in Figure15. I SINK = C VDAC SR DOWN = + VDAC I SOURCE = VDAC Over Current Setting ...

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MAX = R FB ∗ DRP TM Body Braking Related Resistors R TM The body braking during Dynamic VID can be disabled by connecting BBFB pin to ground. If the feature is ...

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Over Temperature Setting Resistors R The threshold voltage of VRHOT comparator is proportional to the die temperature T the relationship between the die temperature of phase IC and the temperature of the power converter according to the power loss, PCB ...

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If the over temperature setting voltage is higher than the phase delay setting voltage, VBIAS*RA HOTSET pin between R and R PHASEx1 respectively. Pre-select R PHASEx1 ( V HOTSET = R PHASEx PHASEx R PHASEx 3 Bootstrap ...

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∗ optional and may be needed in some applications to reduce the jitter caused by the high frequency ...

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π ∗ ∗ π ∗ π ∗ ∗ ...

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DESIGN EXAMPLE 1 - VRM 10 2U CONVERTER SPECIFICATIONS Input Voltage DAC Voltage: V =1.35 V DAC No Load Output Voltage Offset: V Output Current: I =105 ADC O Maximum Output Current: I =120 ADC OMAX ...

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VDAC Slew Rate Programming Capacitor C From Figure 15, the sink current of VDAC pin corresponding to 400kHz (R VDAC down-slope slew-rate programming capacitor from the required down-slope slew rate. − SINK = = C ...

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Body Braking Related Resistors R N/A. The body braking during Dynamic VID is disabled. IR3086 EXTERNAL COMPONENTS PWM Ramp Resistor R and Capacitor C PWMRMP Set PWM ramp magnitude V PWMRMP resistor R , PWMRMP = R PWMRMP ∗ ∗ ...

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Bootstrap Capacitor C BST Choose C =0.1uF BST Decoupling Capacitors for Phase IC and Power Stage Choose C =0.1uF, C =0.1uF VCC VCCL VOLTAGE LOOP COMPENSATION Type II compensation is used for the converter with AL-Polymer output capacitors. Choose the ...

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DESIGN EXAMPLE 2 - EVRD 10 HIGH FREQUENCY ALL-CERAMIC CONVERTER SPECIFICATIONS Input Voltage DAC Voltage: V =1.3 V DAC No Load Output Voltage Offset: V Output Current: I =105 ADC O Maximum Output Current: I =120 ...

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VDAC Slew Rate Programming Capacitor C From Figure 15, the sink current of VDAC pin corresponding to 800kHz (R VDAC down-slope slew-rate programming capacitor from the required down-slope slew rate. − 170 * 10 SINK = = C ...

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Body Braking Related Resistors R N/A. The body braking during Dynamic VID is disabled. IR3086 EXTERNAL COMPONENTS PWM Ramp Resistor R and Capacitor C PWMRMP Set PWM ramp magnitude V PWMRMP resistor R , PWMRMP = R PWMRMP V * ...

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The over temperature setting voltage of Phases 3 and 4 is higher than the phase delay setting voltage, VBIAS*RA Pre-select R PHASEx. PHASEX1 − ∗ HOTSET PHASE 3 BIAS = R PHASE 32 − ...

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PWMRMP PWMRMP SW PWMRMP = F MI − − − PWMRMP DAC ...

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LAYOUT GUIDELINES The following layout guidelines are recommended to reduce the parasitic inductance and resistance of the PCB layout, therefore minimizing the noise coupled to the IC. • Dedicate at least one middle layer for a ground plane LGND. • ...

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PCB Metal and Component Placement • Lead land width should be equal to nominal part lead width. The minimum lead to lead spacing should be ≥ 0.2mm to minimize shorting. • Lead land length should be equal to maximum part ...

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Solder Resist • The solder resist should be pulled away from the metal lead lands by a minimum of 0.06mm. The solder resist mis-alignment is a maximum of 0.05mm and it is recommended that the lead lands are all Non ...

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Stencil Design • The stencil apertures for the lead lands should be approximately 80% of the area of the lead lands. Reducing the amount of solder deposited will minimize the occurrence of lead shorts. Since for 0.5mm pitch devices the ...

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PERFORMANCE CHARACTERISTICS Page Figure 13 - Oscillator Frequency versus ROSC 1000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 200 150 ...

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PACKAGE INFORMATION 28L MLPQ ( Body) – θ IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 www.irf.com Page C/W, θ JA Data and specifications subject ...