PD - 94761 IRF7834 HEXFET® Power MOSFET Applications l Synchronous MOSFET for Notebook Processor Power l Synchronous Rectifier MOSFET for Isolated DC-DC Converters in Networking Systems VDSS Qg (typ.) 30V 4.5m:@VGS = 10V 1 8 S 2 7 S 3 6 4 5 S Benefits l Very Low RDS(on) at 4.5V VGS l Ultra-Low Gate Impedance l Fully Characterized Avalanche Voltage and Current l 20V VGS Max. Gate Rating RDS(on) max G 29nC A A D D D D SO-8 Top View Absolute Maximum Ratings Max. Units Drain-to-Source Voltage Parameter 30 V VGS Gate-to-Source Voltage ± 20 ID @ TA = 25°C Continuous Drain Current, VGS @ 10V 19 ID @ TA = 70°C Continuous Drain Current, VGS @ 10V 16 IDM Pulsed Drain Current 160 PD @TA = 25°C Power Dissipation VDS c PD @TA = 70°C f Power Dissipation f TJ Linear Derating Factor Operating Junction and TSTG Storage Temperature Range A W 2.5 1.6 0.02 -55 to + 150 W/°C °C Thermal Resistance Parameter RθJL RθJA g Junction-to-Ambient fg Junction-to-Drain Lead Notes through www.irf.com Typ. Max. Units ––– 20 °C/W ––– 50 are on page 10 1 2/26/04 IRF7834 Static @ TJ = 25°C (unless otherwise specified) Parameter Min. Typ. Max. Units Conditions BVDSS Drain-to-Source Breakdown Voltage 30 ––– ––– ∆ΒVDSS/∆TJ Breakdown Voltage Temp. Coefficient ––– 0.023 ––– V/°C Reference to 25°C, ID = 1mA RDS(on) Static Drain-to-Source On-Resistance ––– 3.6 4.5 mΩ ––– 4.4 5.5 V VGS = 0V, ID = 250µA VGS = 10V, ID = 19A VGS = 4.5V, ID = 16A VGS(th) Gate Threshold Voltage 1.35 ––– 2.25 V ∆VGS(th) Gate Threshold Voltage Coefficient ––– - 5.2 ––– mV/°C IDSS Drain-to-Source Leakage Current ––– ––– 1.0 µA VDS = 24V, VGS = 0V ––– ––– 150 Gate-to-Source Forward Leakage ––– ––– 100 nA VGS = 20V Gate-to-Source Reverse Leakage ––– ––– -100 Forward Transconductance 85 ––– ––– Total Gate Charge ––– 29 44 Qgs1 Pre-Vth Gate-to-Source Charge ––– 7.5 ––– Qgs2 Post-Vth Gate-to-Source Charge ––– 2.7 ––– Qgd Gate-to-Drain Charge ––– 9.8 ––– ID = 16A Qgodr Gate Charge Overdrive Switch Charge (Qgs2 + Qgd) ––– 9.0 ––– See Fig. 16 Qsw ––– 12.5 ––– IGSS gfs Qg Qoss Output Charge ––– 19 ––– td(on) Turn-On Delay Time ––– 13.7 ––– tr Rise Time ––– 14.3 ––– td(off) Turn-Off Delay Time ––– 18 ––– tf Fall Time ––– 5.0 ––– Ciss Input Capacitance ––– 3710 ––– Coss Output Capacitance ––– 810 ––– Crss Reverse Transfer Capacitance ––– 350 ––– e e VDS = VGS, ID = 250µA VDS = 24V, VGS = 0V, TJ = 125°C VGS = -20V S VDS = 15V, ID = 16A VDS = 15V nC nC VGS = 4.5V VDS = 16V, VGS = 0V VDD = 15V, VGS = 4.5V e ID = 16A ns Clamped Inductive Load pF VDS = 15V VGS = 0V ƒ = 1.0MHz Avalanche Characteristics EAS Parameter Single Pulse Avalanche Energy IAR Avalanche Current c d Typ. ––– Max. 25 Units mJ ––– 16 A Diode Characteristics Parameter Min. Typ. Max. Units IS Continuous Source Current ––– ––– 3.1 ISM (Body Diode) Pulsed Source Current ––– ––– 160 VSD (Body Diode) Diode Forward Voltage ––– ––– 1.0 V trr Reverse Recovery Time ––– 21 32 ns Qrr Reverse Recovery Charge ––– 13 20 nC 2 c Conditions MOSFET symbol A showing the integral reverse p-n junction diode. TJ = 25°C, IS = 16A, VGS = 0V e TJ = 25°C, IF = 16A, VDD = 15V di/dt = 100A/µs e www.irf.com IRF7834 1000 VGS TOP 10V 4.5V 3.8V 3.5V 3.3V 3.0V 2.8V BOTTOM 2.5V 100 10 2.5V 1 > 60µs PULSE WIDTH Tj = 25°C 100 2.5V 10 > 60µs PULSE WIDTH Tj = 150°C 1 0.1 0.1 1 10 0.1 100 1 10 100 VDS, Drain-to-Source Voltage (V) VDS, Drain-to-Source Voltage (V) Fig 1. Typical Output Characteristics Fig 2. Typical Output Characteristics 1.5 RDS(on) , Drain-to-Source On Resistance (Normalized) 1000.00 ID, Drain-to-Source Current (Α) VGS 10V 4.5V 3.8V 3.5V 3.3V 3.0V 2.8V BOTTOM 2.5V TOP ID, Drain-to-Source Current (A) ID, Drain-to-Source Current (A) 1000 100.00 T J = 150°C 10.00 1.00 T J = 25°C 0.10 VDS = 10V > 60µs PULSE WIDTH 0.01 2.0 3.0 VGS, Gate-to-Source Voltage (V) Fig 3. Typical Transfer Characteristics www.irf.com 4.0 ID = 20A VGS = 10V 1.0 0.5 -60 -40 -20 0 20 40 60 80 100 120 140 160 T J , Junction Temperature (°C) Fig 4. Normalized On-Resistance Vs. Temperature 3 IRF7834 100000 12 VGS = 0V, f = 1 MHZ C iss = C gs + C gd, C ds SHORTED VGS, Gate-to-Source Voltage (V) ID= 16A C rss = C gd C, Capacitance (pF) C oss = C ds + C gd 10000 Ciss 1000 Coss Crss VDS= 24V VDS= 15V 10 8 6 4 2 0 100 1 10 0 100 10 20 30 40 50 60 70 QG Total Gate Charge (nC) VDS, Drain-to-Source Voltage (V) Fig 6. Typical Gate Charge Vs. Gate-to-Source Voltage Fig 5. Typical Capacitance Vs. Drain-to-Source Voltage 1000.0 1000 ID, Drain-to-Source Current (A) ISD, Reverse Drain Current (A) OPERATION IN THIS AREA LIMITED BY R DS(on) 100.0 T J = 150°C 10.0 T J = 25°C 1.0 100 10 1 100µsec Tc = 25°C Tj = 150°C Single Pulse VGS = 0V 10msec 0.1 0.1 0.2 0.4 0.6 0.8 1.0 VSD, Source-to-Drain Voltage (V) Fig 7. Typical Source-Drain Diode Forward Voltage 4 1msec 1.2 0 1 10 100 1000 VDS , Drain-toSource Voltage (V) Fig 8. Maximum Safe Operating Area www.irf.com IRF7834 2.2 VGS(th) Gate threshold Voltage (V) 20 ID , Drain Current (A) 16 12 8 4 0 1.8 ID = 250µA 1.4 1.0 25 50 75 100 125 150 -75 -50 -25 T J , Junction Temperature (°C) 0 25 50 75 100 125 150 T J , Temperature ( °C ) Fig 10. Threshold Voltage Vs. Temperature Fig 9. Maximum Drain Current Vs. Case Temperature 100 Thermal Response ( Z thJA ) D = 0.50 0.20 0.10 10 0.05 0.02 0.01 1 τJ 0.1 SINGLE PULSE ( THERMAL RESPONSE ) 0.01 R1 R1 τJ τ1 R2 R2 τ2 τ1 R3 R3 Ri (°C/W) R4 R4 τC τ τ3 τ2 τ3 τ4 τ4 Ci= τi/Ri Ci i/Ri τi (sec) 1.1659 0.000184 9.9439 0.153919 25.520 1.7486 13.380 49 Notes: 1. Duty Factor D = t1/t2 2. Peak Tj = P dm x Zthja + Tc 0.001 1E-006 1E-005 0.0001 0.001 0.01 0.1 1 10 100 t1 , Rectangular Pulse Duration (sec) Fig 11. Maximum Effective Transient Thermal Impedance, Junction-to-Ambient www.irf.com 5 RDS(on), Drain-to -Source On Resistance ( mΩ) IRF7834 20 100 EAS, Single Pulse Avalanche Energy (mJ) ID = 20A 16 12 8 T J = 125°C 4 T J = 25°C 0 2.0 4.0 6.0 8.0 10.0 ID 5.9A 6.7A BOTTOM 16A TOP 80 60 40 20 0 25 VGS, Gate-to-Source Voltage (V) 50 75 100 125 150 Starting T J, Junction Temperature (°C) Fig 12. On-Resistance Vs. Gate Voltage Fig 13c. Maximum Avalanche Energy Vs. Drain Current 15V LD VDS L VDS DRIVER + VDD - D.U.T RG IAS VGS 20V tp + V - DD D.U.T A VGS 0.01Ω Pulse Width < 1µs Duty Factor < 0.1% Fig 13a. Unclamped Inductive Test Circuit V(BR)DSS tp Fig 14a. Switching Time Test Circuit VDS 90% 10% VGS I AS Fig 13b. Unclamped Inductive Waveforms 6 td(on) tr td(off) tf Fig 14b. Switching Time Waveforms www.irf.com IRF7834 D.U.T Driver Gate Drive + P.W. + - - • • • • D.U.T. ISD Waveform Reverse Recovery Current + dv/dt controlled by RG Driver same type as D.U.T. ISD controlled by Duty Factor "D" D.U.T. - Device Under Test VDD P.W. Period * RG D= VGS=10V Circuit Layout Considerations • Low Stray Inductance • Ground Plane • Low Leakage Inductance Current Transformer - Period + - Body Diode Forward Current di/dt D.U.T. VDS Waveform Diode Recovery dv/dt Re-Applied Voltage Body Diode VDD Forward Drop Inductor Curent ISD Ripple ≤ 5% * VGS = 5V for Logic Level Devices Fig 15. Peak Diode Recovery dv/dt Test Circuit for N-Channel HEXFET® Power MOSFETs Id Current Regulator Same Type as D.U.T. Vds Vgs 50KΩ 12V .2µF .3µF D.U.T. + V - DS Vgs(th) VGS 3mA IG ID Current Sampling Resistors Fig 16. Gate Charge Test Circuit www.irf.com Qgs1 Qgs2 Qgd Qgodr Fig 17. Gate Charge Waveform 7 IRF7834 Power MOSFET Selection for Non-Isolated DC/DC Converters Control FET Synchronous 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. The power loss equation for Q2 is approximated by; * Ploss = Pconduction + Pdrive + Poutput ( 2 Ploss = Irms × Rds(on) ) Power losses in the control switch Q1 are given by; + (Qg × Vg × f ) Ploss = Pconduction+ Pswitching+ Pdrive+ Poutput Q + oss × Vin × f + (Qrr × Vin × f ) 2 This can be expanded and approximated by; Ploss = (Irms × Rds(on ) ) *dissipated primarily in Q1. 2 Qgs 2 Qgd +I × × Vin × f + I × × Vin × f ig ig + (Qg × Vg × f ) + Qoss × Vin × f 2 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 Qgs2 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) capacitances 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 IRF7834 SO-8 Package Details D 5 A 8 6 7 6 5 H 1 2 3 0.25 [.010] 4 A MAX MIN .0532 .0688 1.35 1.75 A1 .0040 .0098 0.10 0.25 b .013 .020 0.33 0.51 c .0075 .0098 0.19 0.25 D .189 .1968 4.80 5.00 E .1497 .1574 3.80 4.00 e .050 BASIC 1.27 BAS IC e1 6X e e1 8X b 0.25 [.010] A A1 MILLIMETERS MIN A E INCHES DIM B MAX .025 BASIC 0.635 BAS IC H .2284 .2440 5.80 6.20 K .0099 .0196 0.25 0.50 L .016 .050 0.40 1.27 y 0° 8° 0° 8° K x 45° C y 0.10 [.004] 8X L 8X c 7 C A B FOOT PRINT NOT ES : 1. DIMENS IONING & T OLERANCING PER AS ME Y14.5M-1994. 8X 0.72 [.028] 2. CONT ROLLING DIMENS ION: MILLIMET ER 3. DIMENS IONS ARE S HOWN IN MILLIMET ERS [INCHES ]. 4. OUT LINE CONFORMS T O JEDEC OUT LINE MS -012AA. 5 DIMENS ION DOES NOT INCLUDE MOLD PROT RUS IONS . MOLD PROT RUS IONS NOT T O EXCEED 0.15 [.006]. 6 DIMENS ION DOES NOT INCLUDE MOLD PROT RUS IONS . MOLD PROT RUS IONS NOT T O EXCEED 0.25 [.010]. 6.46 [.255] 7 DIMENS ION IS THE LENGT H OF LEAD F OR S OLDERING T O A S UBS T RAT E. 3X 1.27 [.050] 8X 1.78 [.070] SO-8 Part Marking EXAMPLE: T HIS IS AN IRF7101 (MOSFET ) INT ERNATIONAL RECT IFIER LOGO www.irf.com YWW XXXX F7101 DAT E CODE (YWW) Y = LAS T DIGIT OF T HE YEAR WW = WEEK LOT CODE PART NUMBER 9 IRF7834 SO-8 Tape and Reel TERMINAL NUMBER 1 12.3 ( .484 ) 11.7 ( .461 ) 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. 330.00 (12.992) MAX. 14.40 ( .566 ) 12.40 ( .488 ) NOTES : 1. CONTROLLING DIMENSION : MILLIMETER. 2. OUTLINE CONFORMS TO EIA-481 & EIA-541. Notes: Repetitive rating; pulse width limited by max. junction temperature. Starting TJ = 25°C, L = 0.19mH RG = 25Ω, IAS = 16A. Pulse width ≤ 400µs; duty cycle ≤ 2%. When mounted on 1 inch square copper board Rθ is measured at TJ approximately 90°C 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.2/04 10 www.irf.com