IR3651SPBF International Rectifier, IR3651SPBF Datasheet
IR3651SPBF
Specifications of IR3651SPBF
Related parts for IR3651SPBF
IR3651SPBF Summary of contents
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... Vin: 36V-75V Vin: 12V-100V HDrv Vs R OCset OCset Q2 LDrv PGnd C10 Typical application Circuit ORDERING INFORMATION PIN PARTS PARTS COUNT PER TUBE PER REEL 14 55 ------- 14 -------- 2500 Data Sheet No.PD94720revB IR3651SPBF Vout T&R ORIANTAION Fig A ...
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... These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications are not implied. Package Information 12/07/2010 14-Pin SOIC NB ( Gnd Comp SS/ OCset SYNC 4 11 Vcc Vs PGnd 5 10 Ldrv 6 9 HDrv DRVcc Θ = 88.2 o C/W JA Θ C/W JC IR3651SPBF ...
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... SS Fig. 1: Simplified block diagram of the IR3651 12/07/2010 3V Bias Generator 1.25V POR Vcc LOW HIGH VOLTAGE VOLTAGE LEVEL LEVEL SHIFT SHIFT CIRCUIT Vcc LOW VOLTAGE LEVEL SHIFT R Q PBias S POR IR3651SPBF DETECT HDrv DRVcc UV DETECT 6 LDrv DELAY 5 PGND OCP 12 OCset 10uA 3 ...
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... OCSet Current limit set point. A resistor from this pin to drain of low side MOSFET will set the current limit threshold. 13 Gnd Signal ground for internal reference and control circuitry Connecting a resistor from this pin to ground sets the oscillator frequency. 12/07/2010 IR3651SPBF Description 4 ...
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... Supply ramping up Supply ramping down Supply ramping up and down F Rt=120K S Rt=51K Note2 V ramp D Fb=2V min =200kHz, Note2 F min(ctrl =200kHz, Fb=1.2V max s F =400kHz, Fb=1.2V s 20% above free running freq IR3651SPBF o o =Vb=12V, 0 C<T < 125 Min TYP MAX Unit s 1.25 V -1.5 +1 +1 ...
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... HDrv short circuit pulsed current. PW<10us HDrv short circuit pulsed current. PW<10us LDrv short circuit pulsed current. PW<10us LDrv short circuit pulsed current. PW<10us Deadband Deadband H_to_L L_to_H IR3651SPBF TYP MAX Units μA -0.1 -0.4 μA 85 120 μmho 2400 3000 μ ...
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... IR3651SPBF o C) Transconductance 100 110 120 130 Icc(static 100 110 120 130 ...
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... IR3651SPBF o C) Frequency RT=120K 100 110 120 130 T emp [ C] Max DC @ 200KHz 100 110 120 130 ...
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... MOSFET is generated. Below figure shows a typical Pre- Bias condition at start up. Depends on system configuration, specific amount of output capacitors may be required to prevent discharging the output voltage Volt Pre-Bias Voltage (Output Voltage before startup) IR3651SPBF Switching Frequency vs 100 150 200 250 300 Rt (Kohm) ...
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... Comp 1.25V Fb Fig. 4: Soft-Start circuit for IR3651 Output of UVLO Soft-Start Voltage Current flowing into Fb pin Voltage at negative input of Error Amp voltage Voltage at Fb pin Fig. 5: Theoretical operation waveforms IR3651SPBF 3V 64uA Error Amp 25K 25K POR 3V ≅ 2V ≅ 64uA 0uA ≅ 1.6V 1 ...
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... Ch1: Inductor point, Ch2:Ldrv, Ch3:OCSet The value of R circuit to ensure that the over current protection circuit activates as expected. The IR3651 current limit is designed primarily as disaster preventing, "no blow up" circuit, and doesn't operate as a precision current regulator. IR3651SPBF 10uA Hiccup 3 3uA circuit starts ...
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... The soft-start timing can be programmed by selecting the soft-start capacitance value. The start-up time of the converter can be calculated by using: Where T is the desired start-up time (ms) start For a start-up time of 5ms, the soft-start capacitor will be 0.1uF. Choose a ceramic capacitor at 0.1uF. and R see IR3651SPBF μ ≅ --( ) start 12 ...
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... Therefore ceramic capacitor is selected due to low ESR and small size. In the case of tantalum or low ESR electrolytic capacitors, the ESR dominates the output voltage ripple, equation (9) can be used to calculate the required ESR for the specific voltage ripple. IR3651SPBF are other Δ Δ ...
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... DS(on) loss can be expressed as Where Drain to source voltage at the off time ds(off Rise time Fall time Switching period I = Load current load The switching time waveforms is shown in figure10 90% ϑ ϑ ∗ (ON) d Fig. 10: switching time waveforms IR3651SPBF + off I - -(10 load (OFF ...
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... R osc 3 Where Maximum Input Voltage Oscillator Ramp Voltage osc F = Crossover Frequency Zero Frequency of the Output Capacitor ESR F = Resonant Frequency of the Output Filter LC R and R = Feedback Resistor Dividers Error Amplifier Transconductance m IR3651SPBF -(12) π ∗ 2 ESR Comp E POLE R 3 Frequency F Z ⎞ ...
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... The compensation network has three poles and two zeros and they are expressed as follows π π π -(17 π Cross over frequency is expressed as ⎤ ⎞ ⎟ ⎟ ⎥ ⎠ ⎦ 3 IR3651SPBF E Comp 9 V REF Frequency ≅ π ⎛ ⎞ ⎜ ⎜ ⎟ ⎟ ⎝ ⎠ ≅ π ...
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... The R DS(on) coefficient and it should be considered for the worse case operation. This resistor must be placed close to the IC, place a small ceramic capacitor from this pin to ground for noise rejection purposes. I SET IR3651SPBF approximately one-tenth of o π Θ max , ...
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... Place input capacitor directly to the drain of the high-side MOSFET, to reduce the ESR replace the single input capacitor with two parallel units Part Marking Information 12/07/2010 IR3651SPBF . The feedback part of the system should be kept away from the inductor and other noise sources. The critical ...
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... This product has been designed and qualified for the Industrial market 12/07/2010 Figure A 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 Visit us at www.irf.com for sales contact information Data and specifications subject to change without notice IR3651SPBF TAC Fax: (310) 252-7903 19 ...