IR3081A International Rectifier Corp., IR3081A Datasheet
IR3081A
Related parts for IR3081A
IR3081A Summary of contents
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... ICs” which each drive and monitor a single phase of a multiphase TM converter. The XPhase to design while providing higher efficiency than conventional approaches. The IR3081A is intended for VRD 10 or VRM/EVRD 10 applications that use external VCCVID/VTT circuits. The IR3081A is functionally equivalent to the IR3081, but incorporates the following modifications: • ...
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... BBFB 19 EAOUT RCP VDRP CDRP RDRP1 16 IIN RDRP 15 OCSET ROCSET CFB ROSC RVDAC RFB1 RFB CVDAC IR3081A RMPOUT VBIAS EA CCP 5 Wire Analog Bus to Phase ICs CCP1 ISHARE VDAC VOSENSE+ Remote Sense VOSENSE- Order Quantity 3000 per reel 100 piece strips 1/31 /05 ...
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... IR3081A I I SOURCE SINK 1mA 1mA 10mA 10mA Do Not Connect Do Not Connect 10mA 10mA 1mA 1mA 1mA 1mA 1mA 1mA 1mA 1mA 5mA 5mA 1mA 1mA 10mA 20mA 1mA ...
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... ROSC Note 1 Note 1 VBIAS–VEAOUT (referenced to VBIAS) Normal operation or Fault mode V(VDRP) – V(IIN), 0.8V ≤ V(IIN) ≤ 5.5V Note 1 Note 1 Difference of preconditioning active voltage and SS/DEL-FB offset voltage SS/DEL=0V. IR3081A o o ≤ 14V ≤ T ≤ 100 MIN TYP MAX ...
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... Relative to Charge Voltage, SS/DEL rising Relative to Charge Voltage, SS/DEL falling 1V ≤ V(OCSET) ≤ 41.9kΩ ROSC I(PWRGD) = 4mA V(PWRGD) = 5.5V 0V ≤ V(ENABLE) ≤ VCC Start – Stop -0.3V ≤ VOSNS- ≤ 0.3V, All VID Codes IR3081A MIN TYP MAX UNIT 255 300 345 kHz ...
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... Open Collector output that drives low during Softstart and any external fault condition. Connect external pull-up. 27 N/C No internal connection 28 ENABLE Enable Input. A logic low applied to this pin puts the IC into Fault mode. Page IR3081A TM during transition to a lower VID code. 1/31 /05 ...
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... CURRENT SHARE IR3086A PHASE IC PWM CONTROL 0.1uF VID VOLTAGE PHASE HOT CCS ADDITIONAL PHASES CONTROL BUS Figure 1. System Block Diagram IR3081A GATE VOLTAGE REGULATOR CIN COUT RCS RCS INPUT/OUTPUT 1/31 POWER GOOD PHASE FAULT VR HOT VOUT SENSE+ VOUT+ ...
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... GENERATOR RAMPIN- EAIN RPHS2 PWMRMP RPWMRMP RAMP DISCHARGE SCOMP CLAMP CPWMRMP SHARE CSCOMP ADJUST ERROR AMPLIFIER + ISHARE 10K 20mV - DACIN Figure 2. PWM Block Diagram IR3081A PHASE IC PWM LATCH GATEH S PWM RESET COMPARATOR DOMINANT - R GATEL + ENABLE + BODY - BRAKING COMPARATOR X 0.91 CURRENT SENSE CSIN+ ...
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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 IR3081A 1/31 /05 ...
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... Figure 4. PWM Operating Waveforms − MAX MIN T SLEW V O − MAX MIN T SLEW + BODYDIODE IR3081A DUTY CYCLE DECREASE DUE TO LOAD STEADY-STATE DECREASE (BODY BRAKING) OR FAULT OPERATION (VCC UV, OCP, VID=11111X 1/31 /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 IR3081A 1/31 /05 ...
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... IR3081A THEORY OF OPERATION Block Diagram The Block diagram of the IR3081A is shown in Fig. 6, and specific features are discussed in the following sections. VCC UVLO COMPARATOR VCC - START STOP + + 9.7V 0.2V 8.9V - ENABLE COMPARATOR ENABLE - + 65mV + 115mV 0. VCHG 3. IDISCHG IDISCHG 6uA OFF ICHG ICHG 70uA SS/DEL VID5 ...
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... The IR3081A 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 of the voltage at the VDAC pin can be adjusted by an external capacitor between VDAC pin and the VOSNS- pin ...
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... Table 1. Voltage Identification (VID) is selected to program the desired amount of fixed offset voltage below the FB . When the load current increases, the adaptive DRP IR3081A VID3 VID2 VID1 VID0 VID5 ...
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... Amplifier Phase IC VDRP - IIN ISHARE ISHARE ISHARE ISHARE + VDAC Figure 8. Adaptive voltage positioning Control IC Error Amplifier VDAC + EAOUT - RFB FB IFB RFB2 RDRP AVP Amplifier VDRP - IIN IIN + IR3081A Current Sense Amplifier CSIN+ + CSIN- - 10k Current Sense Amplifier CSIN+ + CSIN- - 10k Vo Rt 1/31 /05 ...
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... The UVLO function monitors the IR3081A’s VCC supply pin and ensures that IR3081A has a high enough voltage to power the internal circuit. The IR3081A’s UVLO is set higher than the minimum operating voltage of compatible Phase ICs thus providing UVLO protection for them as well. During power-up the fault latch is reset when VCC exceeds 9 ...
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... V(EAOUT) jumps above 0.6V, the precondition latch is reset and the IIN clamp is removed. Normal current sharing in the phase ICs then resumes. Page OCP THRESHOLD HICCUP OVER-CURRENT PROTECTION OCP DELAY Figure 10. Operating Waveforms IR3081A 8.9V UVLO RE-START POWER-DOWN AFTER (VCC GATES OCP FAULT MODE) ...
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... VID1 FB VID2 VID2 VDRP RDRP1 VID3 6 16 VID3 IIN VID4 7 15 VID4 OCSET ROCSET ROSC RVDAC CVDAC Figure 11. IR3081A/IR3086A Six-Phase VRM/EVRD 10 Converter Page RBIASIN 20k 1 RMPIN+ 2 IR3086A RMPIN- PHASE 3 HOTSET IC 4 VRHOT 5 ISHARE CFB RFB1 RFB CSCOMP RBBDRP RCP ...
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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. ...
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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 IR3081A and room temperature L_MAX T )] (8) ROOM − (9) ROOM (10) LIMIT (11 MIN ...
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... HOTSET1 HOTSET2 − 241 J can be calculated as follows. HOTSET2 ∗ HOTSET − V BIAS HOTSET IR3081A PWMRMP should be connected to the input of the RAMP (15) − − DAC PWMRMP CS- CS+ and calculate R CS+ (16) should be added between the amplifier inverting (17) CS+ (º ...
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... RMPIN+ or RMPIN- between R PHASEx2 , − ∗ ∗ PHASEx BIAS PHASEx 1 − BIAS HOTSET ∗ BIAS PHASEx 1 − BIAS HOTSET IR3081A (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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... E FB PWMRMP π ∗ DRP ∗ IR3081A 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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... V O ∗ DRP ∗ ∗ ∗ ∗ PWMRMP ∗ ∗ ∗ ∗ ∗ IR3081A (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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... V I PWMRMP Page and determine the C , C), SCOMP π ROOM LE CI π 6 ∗ ∗ PWMRMP SW PWMRMP − − DAC I DAC IR3081A ) based on the (40) ( 41) 1/31 /05 ...
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... SW Output Inductors: L=220 nH, R =0.47 mΩ L Output Capacitors: AL-Polymer, C=560uF, R IR3081A EXTERNAL COMPONENTS Oscillator Resistor Rosc Once the switching frequency is chosen, R frequency of 400kHz per phase, choose R Soft Start Capacitor C SS/DEL Determine the soft start capacitor from the required soft start time. ...
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... R 3 ∗ TOFST − 3 ∗ ∗ Ω − 3 ∗ IR3081A VDAC =30.1kΩ) is 76uA. Calculate the OSC − 6 ∗ − = Ω 100 − 6 ∗ − 101 41uA with OCSET 3 ∗ ...
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... RA PHASE4 PHASE5 = PHASE31 PHASE41 PHASE51 . 0 628 3 ∗ = Ω − 628 =3.24kΩ, P PHASE42 PHASE52 IR3081A , and calculate the PWMRMP )] =16.2kΩ PWMRMP CS- , CS- PHASE1 =0.637 starting from down- PHASE5 = R =10kΩ, PHASE61 =7.87kΩ, R =17.4kΩ PHASE62 1/31 =0.628, /05 ...
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... O CI − π − 4 π − ∗ ∗ 105 * . IR3081A . CP − 6 ∗ ∗ ∗ ∗ ( 560 365 Ω − − 560 * =68nF CP and calculate ...
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... SW Output Inductors: L=100 nH, R =0.5 mΩ L Output Capacitors: Ceramic, C=22uF, R IR3081A EXTERNAL COMPONENTS Oscillator Resistor Rosc Once the switching frequency is chosen, R switching frequency of 800kHz per phase, choose R Soft Start Capacitor C SS/DEL Determine the soft start capacitor from the required soft start time. ...
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... O = − − 3 ∗ Ω 576 − 3 ∗ and R BBFB BBDRP IR3081A − 6 ∗ − = Ω 100 − 6 ∗ − 101 90uA with OCSET 3 ∗ 800 * DRP − ...
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... PHASE 31 = − ∗ ∗ 198 Ω − IR3081A , and calculate the PWMRMP )] Ω CS- , CS- R and R PHASEx1, PHASEx2 PHASEx3 =0.597 starting from down- PHASE5 Ω ∗ Ω 887 1/31 =0 ...
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... − 3 π 3500 * 22 − 4 π − ∗ ∗ 105 * . 3500 IR3081A = 146 kHz − − 6 ∗ ∗ ∗ 162 * . − and calculate SCOMP ...
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... OCSET VDAC VDAC VCC VCC VCC LGND LGND RMPOUT RMPOUT SS/DEL SS/DEL PWRGD PWRGD ENABLE ENABLE To SYSTEM To SYSTEM IR3081A , and C . Avoid using any via for the SS/DEL VDAC VDAC ROSC ROSC VOSNS- VOSNS- To Voltage To Voltage Remote Sense Remote Sense 1/31 /05 ...
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... Copper (≥ 0.1mm for 1 oz. Copper and ≥ 0.23mm for 3 oz. Copper) • A single 0.30mm diameter via shall be placed in the center of the pad land and connected to ground to minimize the noise effect on the IC. Page IR3081A 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. • The single via in the land pad should be tented with solder resist 0.4mm diameter, or 0.1mm larger than the diameter of the via. Page IR3081A 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 IR3081A 1/31 /05 ...
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... ROSC (K Ohm) IR3081A 100 100 ISINK ISOURCE FB, BBFB, OCSET Bias Current VDAC Sink Current VDAC Source Current 1/31 /05 ...
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... C/W, θ JA 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. IR3081A C/W JC TAC Fax: (310) 252-7903 1/31 ...