IRLU8721PBF

Applications l High Frequency Synchronous Buck Converters for Computer Processor Power l High Frequency Isolated DC-DC Converters with Synchronous Rectification for Telecom and Industrial Use l Lead-Free Benefits l Very Low RDS(on) at 4.5V VGS l Ultra-Low Gate Impedance l Fully Characterized Avalanche Voltage and Current HEXFET Power MOSFET IRLR8721PbF IRLU8721PbF ® 8.4m: PD - 96119 VDSS RDS(on) max 30V D Qg 8.5nC S G S D G D-Pak I-Pak IRLR8721PbF IRLU8721PbF G Gate D Drain S Source Absolute Maximum Ratings Parameter VDS VGS ID @ TC = 25°C ID @ TC = 100°C IDM PD @TC = 25°C PD @TC = 100°C TJ TSTG Drain-to-Source Voltage Gate-to-Source Voltage Continuous Drain Current, VGS @ 10V Continuous Drain Current, VGS @ 10V Pulsed Drain Current Max. 30 ± 20 65 46 Units V ™ f f A 260 65 33 0.43 -55 to + 175 W W/°C °C Maximum Power Dissipation Maximum Power Dissipation Linear Derating Factor Operating Junction and Storage Temperature Range Thermal Resistance Parameter RθJC RθJA RθJA Junction-to-Case Junction-to-Ambient (PCB Mount) Junction-to-Ambient Typ. Max. 2.3 50 110 Units °C/W gà ––– ––– ––– Notes  through … are on page 11 www.irf.com 1 08/10/07 IRLR/U8721PbF Static @ TJ = 25°C (unless otherwise specified) Parameter BVDSS ∆ΒVDSS/∆TJ RDS(on) VGS(th) ∆VGS(th) IDSS IGSS gfs Qg Qgs1 Qgs2 Qgd Qgodr Qsw Qoss RG td(on) tr td(off) tf Ciss Coss Crss Drain-to-Source Breakdown Voltage Breakdown Voltage Temp. Coefficient Static Drain-to-Source On-Resistance Gate Threshold Voltage Gate Threshold Voltage Coefficient Drain-to-Source Leakage Current Gate-to-Source Forward Leakage Gate-to-Source Reverse Leakage Forward Transconductance Total Gate Charge Pre-Vth Gate-to-Source Charge Post-Vth Gate-to-Source Charge Gate-to-Drain Charge Gate Charge Overdrive Switch Charge (Qgs2 + Qgd) Output Charge Gate Resistance Turn-On Delay Time Rise Time Turn-Off Delay Time Fall Time Input Capacitance Output Capacitance Reverse Transfer Capacitance Parameter Single Pulse Avalanche Energy Avalanche Current Repetitive Avalanche Energy Min. Typ. Max. Units 30 ––– ––– ––– 1.35 ––– ––– ––– ––– ––– 46 ––– ––– ––– ––– ––– ––– ––– ––– ––– ––– ––– ––– ––– ––– ––– ––– 21 6.3 10.1 1.9 -6.8 ––– ––– ––– ––– ––– 8.5 1.9 1.2 3.4 2.0 4.6 7.9 2.3 8.8 30 9.4 6.5 1030 350 110 ––– ––– Conditions V VGS = 0V, ID = 250µA mV/°C Reference to 25°C, ID = 1mA mΩ VGS = 10V, ID = 25A 8.4 11.8 VGS = 4.5V, ID = 20A 2.35 V VDS = VGS, ID = 25µA ––– mV/°C 1.0 150 100 -100 ––– 13 ––– ––– ––– ––– ––– ––– 3.8 ––– ––– ––– ––– ––– ––– ––– Typ. ––– ––– ––– pF nC Ω µA nA S f f VDS = 24V, VGS = 0V VDS = 24V, VGS = 0V, TJ = 125°C VGS = 20V VGS = -20V VDS = 15V, ID = 20A VDS = 15V VGS = 4.5V ID = 20A See Fig. 16 VDS = 16V, VGS = 0V VDD = 15V, VGS = 4.5V ID = 20A nC f ns RG = 1.8Ω See Fig. 14 VGS = 0V VDS = 15V ƒ = 1.0MHz Max. 93 20 6.5 Units mJ A mJ Avalanche Characteristics EAS IAR EAR Ù dh ™ ––– ––– ––– ––– ––– ––– ––– ––– 17 24 Diode Characteristics Parameter IS ISM VSD trr Qrr ton Continuous Source Current (Body Diode) Pulsed Source Current (Body Diode) Diode Forward Voltage Reverse Recovery Time Reverse Recovery Charge Forward Turn-On Time Min. Typ. Max. Units 65 f Conditions MOSFET symbol showing the integral reverse G D A Ùh 260 1.0 26 36 V ns nC S p-n junction diode. TJ = 25°C, IS = 20A, VGS = 0V TJ = 25°C, IF = 20A, VDD = 15V di/dt = 300A/µs f f Intrinsic turn-on time is negligible (turn-on is dominated by LS+LD) 2 www.irf.com IRLR/U8721PbF 1000 TOP VGS 10V 8.0V 5.0V 4.5V 4.0V 3.5V 3.0V 2.7V 1000 TOP VGS 10V 8.0V 5.0V 4.5V 4.0V 3.5V 3.0V 2.7V ID, Drain-to-Source Current (A) 100 BOTTOM ID, Drain-to-Source Current (A) 100 BOTTOM 10 10 2.7V 1 2.7V ≤60µs PULSE WIDTH 0.1 0.1 1 Tj = 25°C 1 100 0.1 1 10 ≤60µs PULSE WIDTH Tj = 175°C 10 100 V DS, Drain-to-Source Voltage (V) V DS, Drain-to-Source Voltage (V) Fig 1. Typical Output Characteristics Fig 2. Typical Output Characteristics 1000 2.0 RDS(on) , Drain-to-Source On Resistance (Normalized) ID, Drain-to-Source Current (A) ID = 25A VGS = 10V 100 T J = 175°C 1.5 10 1 T J = 25°C VDS = 15V ≤60µs PULSE WIDTH 1.0 0.1 0 2 4 6 8 10 0.5 -60 -40 -20 0 20 40 60 80 100 120140160 180 T J , Junction Temperature (°C) VGS, Gate-to-Source Voltage (V) Fig 3. Typical Transfer Characteristics Fig 4. Normalized On-Resistance vs. Temperature www.irf.com 3 IRLR/U8721PbF 10000 VGS = 0V, f = 1 MHZ C iss = C gs + C gd, C ds SHORTED C rss = C gd C oss = C ds + C gd 5.0 ID= 20A VGS, Gate-to-Source Voltage (V) 4.0 VDS= 24V VDS= 15V VDS= 6.0V C, Capacitance (pF) 1000 Ciss Coss Crss 3.0 2.0 100 1.0 10 1 10 VDS, Drain-to-Source Voltage (V) 100 0.0 0 2 4 6 8 10 QG, Total Gate Charge (nC) Fig 5. Typical Capacitance vs. Drain-to-Source Voltage Fig 6. Typical Gate Charge vs. Gate-to-Source Voltage 1000 1000 OPERATION IN THIS AREA LIMITED BY R DS(on) 100µsec 1msec 100 ID, Drain-to-Source Current (A) ISD, Reverse Drain Current (A) T J = 175°C T J = 25°C 100 10 10 10msec 1 Tc = 25°C Tj = 175°C Single Pulse 0.1 0 1 10 100 1 VGS = 0V 0.1 0.0 0.5 1.0 1.5 2.0 VSD, Source-to-Drain Voltage (V) VDS, Drain-to-Source Voltage (V) Fig 7. Typical Source-Drain Diode Forward Voltage Fig 8. Maximum Safe Operating Area 4 www.irf.com IRLR/U8721PbF 70 60 ID, Drain Current (A) 2.5 VGS(th) , Gate Threshold Voltage (V) Limited By Package 50 40 30 20 10 0 25 50 75 100 125 150 175 T C , Case Temperature (°C) 2.0 1.5 ID = 25µA 1.0 0.5 -75 -50 -25 0 25 50 75 100 125 150 175 200 T J , Temperature ( °C ) Fig 9. Maximum Drain Current vs. Case Temperature Fig 10. Threshold Voltage vs. Temperature 10 Thermal Response ( Z thJC ) °C/W 1 D = 0.50 0.20 0.10 0.05 0.02 0.01 τJ τJ τ1 0.1 R1 R1 τ2 R2 R2 R3 R3 τ3 τC τ τ3 Ri (°C/W) τi (sec) 0.3501 0.000072 1.1877 0.7635 0.001239 0.010527 τ1 τ2 0.01 SINGLE PULSE ( THERMAL RESPONSE ) 1E-005 0.0001 Ci= τi /Ri Ci i/Ri Notes: 1. Duty Factor D = t1/t2 2. Peak Tj = P dm x Zthjc + Tc 0.001 0.01 0.1 0.001 1E-006 t1 , Rectangular Pulse Duration (sec) Fig 11. Maximum Effective Transient Thermal Impedance, Junction-to-Case www.irf.com 5 IRLR/U8721PbF 15V 400 EAS , Single Pulse Avalanche Energy (mJ) 350 300 250 200 150 100 50 0 25 50 75 100 VDS L DRIVER ID 1.1A 1.4A BOTTOM 20A TOP RG 20V D.U.T IAS tp + - VDD A 0.01Ω Fig 12a. Unclamped Inductive Test Circuit V(BR)DSS tp 125 150 175 Starting T J , Junction Temperature (°C) Fig 12c. Maximum Avalanche Energy vs. Drain Current I AS RD Fig 12b. Unclamped Inductive Waveforms V GS Current Regulator Same Type as D.U.T. V DS RG VGS D.U.T. + -V DD 50KΩ 12V .2µF .3µF Pulse Width ≤ 1 µs Duty Factor ≤ 0.1 % Fig 14a. Switching Time Test Circuit D.U.T. + V - DS VDS 90% VGS 3mA IG ID 10% VGS td(on) tr t d(off) tf Current Sampling Resistors Fig 13. Gate Charge Test Circuit Fig 14b. Switching Time Waveforms 6 www.irf.com IRLR/U8721PbF D.U.T Driver Gate Drive + P.W. Period D= P.W. Period VGS=10V ƒ + Circuit Layout Considerations • Low Stray Inductance • Ground Plane • Low Leakage Inductance Current Transformer * D.U.T. ISD Waveform Reverse Recovery Current Body Diode Forward Current di/dt D.U.T. VDS Waveform Diode Recovery dv/dt ‚ - - „ +  RG • • • • dv/dt controlled by R G Driver same type as D.U.T. I SD controlled by Duty Factor "D" D.U.T. - Device Under Test V DD VDD + - Re-Applied Voltage Inductor Curent Body Diode Forward Drop Ripple ≤ 5% ISD * VGS = 5V for Logic Level Devices Fig 15. Peak Diode Recovery dv/dt Test Circuit for N-Channel HEXFET® Power MOSFETs Id Vds Vgs Vgs(th) Qgodr Qgd Qgs2 Qgs1 Fig 16. Gate Charge Waveform www.irf.com 7 IRLR/U8721PbF Power MOSFET Selection for Non-Isolated DC/DC Converters Control FET Special attention has been given to the power losses in the switching elements of the circuit - Q1 and Q2. Power losses in the high side switch Q1, also called the Control FET, are impacted by the Rds(on) of the MOSFET, but these conduction losses are only about one half of the total losses. Power losses in the control switch Q1 are given by; Synchronous FET The power loss equation for Q2 is approximated by; * Ploss = Pconduction + P + Poutput drive Ploss = Irms × Rds(on) + ( g × Vg × f ) Q ( 2 ) Ploss = Pconduction+ Pswitching+ Pdrive+ Poutput This can be expanded and approximated by; ⎛Q ⎞ + ⎜ oss × Vin × f + (Qrr × Vin × f ) ⎝2 ⎠ *dissipated primarily in Q1. Ploss = (Irms 2 × Rds(on ) ) ⎛ Qgd +⎜I × × Vin × ig ⎝ + (Qg × Vg × f ) + ⎛ Qoss × Vin × f ⎞ ⎝2 ⎠ ⎞⎛ Qgs 2 ⎞ f⎟ + ⎜ I × × Vin × f ⎟ ig ⎠⎝ ⎠ This simplified loss equation includes the terms Qgs2 and Qoss which are new to Power MOSFET data sheets. Qgs2 is a sub element of traditional gate-source charge that is included in all MOSFET data sheets. The importance of splitting this gate-source charge into two sub elements, Qgs1 and Qgs2, can be seen from Fig 16. Qgs2 indicates the charge that must be supplied by the gate driver between the time that the threshold voltage has been reached and the time the drain current rises to Idmax at which time the drain voltage begins to change. Minimizing Q gs2 is a critical factor in reducing switching losses in Q1. Qoss is the charge that must be supplied to the output capacitance of the MOSFET during every switching cycle. Figure A shows how Qoss is formed by the parallel combination of the voltage dependant (nonlinear) capacitance’s Cds and Cdg when multiplied by the power supply input buss voltage. For the synchronous MOSFET Q2, Rds(on) is an important characteristic; however, once again the importance of gate charge must not be overlooked since it impacts three critical areas. Under light load the MOSFET must still be turned on and off by the control IC so the gate drive losses become much more significant. Secondly, the output charge Qoss and reverse recovery charge Qrr both generate losses that are transfered to Q1 and increase the dissipation in that device. Thirdly, gate charge will impact the MOSFETs’ susceptibility to Cdv/dt turn on. The drain of Q2 is connected to the switching node of the converter and therefore sees transitions between ground and Vin. As Q1 turns on and off there is a rate of change of drain voltage dV/dt which is capacitively coupled to the gate of Q2 and can induce a voltage spike on the gate that is sufficient to turn the MOSFET on, resulting in shoot-through current . The ratio of Qgd/Qgs1 must be minimized to reduce the potential for Cdv/dt turn on. Figure A: Qoss Characteristic 8 www.irf.com IRLR/U8721PbF D-Pak (TO-252AA) Package Outline Dimensions are shown in millimeters (inches) D-Pak (TO-252AA) Part Marking Information @Y6HQG@) UCDTÃDTÃ6IÃDSAS XDUCÃ6TT@H7G` GPUÃ8P9@à !"# %Ã! ! Q6SUÃIVH7@S DIU@SI6UDPI6G S@8UDAD@S GPBP 6TT@H7G@9ÃPIÃXXà DIÃUC@Ã6TT@H7G`ÃGDI@ÃÅ6Å ,5)5 $   96U@Ã8P9@ `@6Sà X@@Fà GDI@Ã6 Ã2Ã! % I‚‡r)ÃÅQÅÃvÃh††r€iy’Ãyvr†v‡v‚ vqvph‡r†ÃÅGrhqA…rrÅ 6TT@H7G` GPUÃ8P9@ ÅQÅÃvÃh††r€iy’Ãyvr†v‡v‚Ãvqvph‡r† ÅGrhqA…rrÅĈhyvsvph‡v‚Ã‡‚ÇurÃp‚†ˆ€r…yr‰ry 25 Q6SUÃIVH7@S DIU@SI6UDPI6G S@8UDAD@S GPBP 96U@Ã8P9@ QÃ2Ã9@TDBI6U@TÃG@69AS@@ QSP9V8UÃPQUDPI6G QÃ2Ã9@TDBI6U@TÃG@69AS@@ QSP9V8UÃRV6GDAD@9ÃUPÃUC@ 8PITVH@SÃG@W@GÃPQUDPI6G `@6Sà X@@Fà Ã2Ã! % ,5)5   6TT@H7G` GPUÃ8P9@ 6Ã2Ã6TT@H7G`ÃTDU@Ã8P9@ Note: For the most current drawing please refer to IR website at http://www.irf.com/package/ www.irf.com 9 IRLR/U8721PbF I-Pak (TO-251AA) Package Outline Dimensions are shown in millimeters (inches) I-Pak (TO-251AA) Part Marking Information @Y6HQG@) UCDTÃDTÃ6IÃDSAV ! XDUCÃ6TT@H7G` GPUÃ8P9@Ã$%&' 6TT@H7G@9ÃPIÃXXà (Ã! DIÃUC@Ã6TT@H7G`ÃGDI@ÃÅ6Å I‚‡r)ÃÅQÅÃvÃh††r€iy’Ãyvr†v‡v‚ vqvph‡r†ÃGrhqA…rrÅ DIU@SI6UDPI6G S@8UDAD@S GPBP 6TT@H7G` GPUÃ8P9@ Q6SUÃIVH7@S ,5)8 $   96U@Ã8P9@ `@6Sà Ã2Ã! X@@Fà ( GDI@Ã6 25 DIU@SI6UDPI6G S@8UDAD@S GPBP 6TT@H7G` GPUÃ8P9@ Q6SUÃIVH7@S ,5)8   96U@Ã8P9@ QÃ2Ã9@TDBI6U@TÃG@69AS@@ QSP9V8UÃPQUDPI6G `@6Sà Ã2Ã! X@@Fà ( 6Ã2Ã6TT@H7G`ÃTDU@Ã8P9@ Note: For the most current drawing please refer to IR website at http://www.irf.com/package/ 10 www.irf.com IRLR/U8721PbF D-Pak (TO-252AA) Tape & Reel Information Dimensions are shown in millimeters (inches) TR TRR TRL 16.3 ( .641 ) 15.7 ( .619 ) 16.3 ( .641 ) 15.7 ( .619 ) 12.1 ( .476 ) 11.9 ( .469 ) FEED DIRECTION 8.1 ( .318 ) 7.9 ( .312 ) FEED DIRECTION NOTES : 1. CONTROLLING DIMENSION : MILLIMETER. 2. ALL DIMENSIONS ARE SHOWN IN MILLIMETERS ( INCHES ). 3. OUTLINE CONFORMS TO EIA-481 & EIA-541. 13 INCH 16 mm NOTES : 1. OUTLINE CONFORMS TO EIA-481. Note: For the most current drawing please refer to IR website at http://www.irf.com/package/ Notes:  Repetitive rating; pulse width limited by max. junction temperature. ‚ Starting TJ = 25°C, L = 0.47mH RG = 25 Ω, IAS = 20A. ƒ Pulse width ≤ 400µs; duty cycle ≤ 2%. „ Calculated continuous current based on maximum allowable junction temperature. Package limitation current is 50A. … When mounted on 1" square PCB (FR-4 or G-10 Material). For recommended footprint and soldering techniques refer to application note #AN-994. Data and specifications subject to change without notice. This product has been designed and qualified for the Industrial market. Qualification Standards can be found on IR’s Web site. IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 TAC Fax: (310) 252-7903 Visit us at www.irf.com for sales contact information.08/2007 www.irf.com 11