PD-94108 IRF7807V • • • • N Channel Application Specific MOSFET Ideal for Mobile DC-DC Converters Low Conduction Losses Low Switching Losses Description This new device employs advanced HEXFET Power MOSFET technology to achieve an unprecedented balance of on-resistance and gate charge. The reduction of conduction and switching losses makes it ideal for high efficiency DC-DC Converters that power the latest generation of mobile microprocessors. A pair of IRF7807V devices provides the best cost/ performance solution for system voltages, such as 3.3V and 5V. A D 1 8 S 2 7 D S 3 6 D G 4 5 D S SO-8 T o p V ie w DEVICE CHARACTERISTICS IRF7807V RDS(on) 17mΩ QG 9.5nC Qsw 3.4nC Qoss 12nC Absolute Maximum Ratings Parameter Drain-Source Voltage Gate-Source Voltage Continuous Drain or Source TA = 25°C Current (VGS ≥ 4.5V) TA = 70°C Pulsed Drain Current Power Dissipation TA = 25°C Symbol IRF7807 V VDS 30 VGS ±20 ID 8.3 6.6 IDM 66 PD 2.5 TA = 70°C Units V A W 1.6 TJ, TSTG –55 to 150 °C Continuous Source Current (Body Diode) IS 2.5 A Pulsed Source Current ISM 66 Parameter Maximum Junction-to-Ambient RθJA Max. 50 Units °C/W Maximum Junction-to-Lead RθJL 20 °C/W Junction & Storage Temperature Range Thermal Resistance 3/1/01 IRF7807V Electrical Characteristics Parameter Min Typ Max Units 30 – – V 17 25 mΩ Drain-to-Source Breakdown Voltage BVDSS Static Drain-Source on Resistance RDS(on) Gate Threshold Voltage VGS(th) Drain-Source Leakage Current IDSS Gate-Source Leakage Current* IGSS Total Gate Charge* QG 9.5 Pre-Vth Gate-Source Charge QGS1 2.3 Post-Vth Gate-Source Charge QGS2 1.0 Gate to Drain Charge QGD 2.4 Switch Chg(Qgs2 + Qgd) Qsw 3.4 5.2 16.8 1.0 VGS = 4.5V, ID = 7.0A V VDS = VGS,ID = 250µA 100 µA VDS = 24V, VGS = 0, ±100 nA 20 Current* Conditions VGS = 0V, ID = 250µA VDS = 24V, VGS = 0 Tj = 100°C Output Charge* Qoss 12 RG 2.0 Turn-on Delay Time td (on) 6.3 Rise Time tr 1.2 Turn-off Delay Time td tf VGS=5V, ID=7.0A VDS = 16V Gate Resistance Fall Time 14 VGS = ±20V nC VDS = 16V, VGS = 0 Ω VDD = 16V, ID = 7.0A ns 11 (off) VGS = 5V, RG= 2Ω Resistive Load 2.2 Source-Drain Rating & Characteristics Parameter Min Diode Forward Voltage* VSD Reverse Recovery Charge Qrr Reverse Recovery Charge (with Parallel Schottky) Qrr(s) Notes: * 2 Typ 64 Max Units Conditions 1.2 V IS = 7.0A, VGS = 0V nC di/dt ~ 700A/µs VDS = 16V, VGS = 0V, IS = 7.0A 41 nC di/dt = 700A/µs (with 10BQ040) VDS = 16V, VGS = 0V, IS = 7.0A Repetitive rating; pulse width limited by max. junction temperature. Pulse width ≤ 400 µs; duty cycle ≤ 2%. When mounted on 1 inch square copper board Typ = measured - Qoss Typical values of RDS(on) measured at VGS = 4.5V, QG, QSW and QOSS measured at VGS = 5.0V, IF = 7.0A. Device are 100% tested to these parameters. www.irf.com IRF7807V Power MOSFET Selection for DC/DC Converters 4 Drain Current Control FET t2 t3 t1 VGTH t0 2 QGD Ploss = Pconduction+ Pswitching+ Pdrive+ Poutput Gate Voltage QGS2 Power losses in the control switch Q1 are given by; 1 QGS1 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 R ds(on) of the MOSFET, but these conduction losses are only about one half of the total losses. Drain Voltage This can be expanded and approximated by; Ploss = (Irms 2 × Rds(on ) ) Q Q + I × gd × Vin × f + I × gs2 × 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 1. Qgs2 indicates the charge that must be supplied by the gate driver between the time that the threshold voltage has been reached (t1) and the time the drain current rises to Idmax (t2) 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 2 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. www.irf.com Figure 1: Typical MOSFET switching waveform Synchronous FET The power loss equation for Q2 is approximated by; * Ploss = Pconduction + Pdrive + Poutput ( 2 Ploss = Irms × Rds(on) ) + (Qg × Vg × f ) Q + oss × Vin × f + (Qrr × Vin × f ) 2 *dissipated primarily in Q1. 3 IRF7807V 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. Spice model for IRF7807V can be downloaded in machine readable format at www.irf.com. Figure 2: Qoss Characteristic Typical Mobile PC Application The performance of these new devices has been tested in circuit and correlates well with performance predictions generated by the system models. An advantage of this new technology platform is that the MOSFETs it produces are suitable for both control FET and synchronous FET applications. This has been demonstrated with the 3.3V and 5V converters. (Fig 3 and Fig 4). In these applications the same MOSFET IRF7807V was used for both the control FET (Q1) and the synchronous FET (Q2). This provides a highly effective cost/performance solution. 5.0V Supply : Q1=Q2= IRF7807V 93 95 92 94 91 93 90 92 Efficiency (%) Efficiency (%) 3.3V Supply : Q1=Q2= IRF7807V 89 88 87 86 Vin=24V 85 Vin=14V 84 Vin=10V 90 Vin=24V 89 Vin=14V 88 Vin=10V 87 86 83 1 2 3 Load current (A) Figure 3 4 91 4 5 1 2 3 4 5 Load current (A) Figure 4 www.irf.com IRF7807V 5 ID = 7.0A 1.5 1.0 0.5 0.0 -60 -40 -20 ID = 7.0A VDS = 16V VGS , Gate-to-Source Voltage (V) R DS(on) , Drain-to-Source On Resistance (Normalized) 2.0 4 3 2 1 VGS = 4.5V 0 20 40 60 0 80 100 120 140 160 0 TJ , Junction Temperature ( °C) 4 6 8 10 12 QG , Total Gate Charge (nC) Fig 6. Typical Gate Charge Vs. Gate-to-Source Voltage Fig 5. Normalized On-Resistance Vs. Temperature 100 0.030 ISD , Reverse Drain Current (A) R DS(on) , Drain-to -Source On Resistance ( Ω ) 2 0.025 0.020 ID = 7.0A 0.015 0.010 2.0 4.0 6.0 8.0 10.0 12.0 14.0 VGS, Gate -to -Source Voltage (V) Fig 7. On-Resistance Vs. Gate Voltage www.irf.com 16.0 TJ = 150 ° C 10 TJ = 25 ° C 1 0.1 0.2 V GS = 0 V 0.4 0.6 0.8 1.0 1.2 VSD ,Source-to-Drain Voltage (V) Fig 8. Typical Source-Drain Diode Forward Voltage 5 IRF7807V Thermal Response (Z thJA ) 100 D = 0.50 10 0.20 0.10 0.05 PDM 0.02 1 t1 0.01 t2 SINGLE PULSE (THERMAL RESPONSE) 0.1 0.00001 0.0001 Notes: 1. Duty factor D = t 1 / t 2 2. Peak T J = P DM x Z thJA + TA 0.001 0.01 0.1 1 10 t1 , Rectangular Pulse Duration (sec) Figure 9. Maximum Effective Transient Thermal Impedance, Junction-to-Ambient 6 www.irf.com IRF7807V SO-8 Package Details D IM D -B - 5 8 E -A - 1 7 2 5 A 6 3 e 6X 5 H 0.2 5 (.0 10 ) 4 M A M θ e1 K x 45 ° -C- 0 .10 (.00 4) B 8X 0 .25 (.01 0) A1 L 8X 6 C 8X M C A S B S N O TE S : 1 . D IM EN SIO N IN G AN D TO L ER A NC IN G P ER AN S I Y1 4.5 M -198 2. 2 . C O N TRO L LIN G D IM EN SIO N : IN C H . 3 . D IM EN SIO N S A RE SH O W N IN M ILLIM E TE R S (IN C HE S). 4 . O U TLIN E CO N F O RM S TO JED E C O U TLINE M S -0 12 AA . 5 D IM E NS IO N D O ES N O T IN C LU D E M O LD PR O TR US IO N S M O LD P R O TR U SIO NS N O T TO EXCE ED 0 .2 5 (.00 6). 6 D IM E NS IO N S IS TH E LE N G TH O F L EA D FO R SO L DE R IN G TO A SU B STRA TE.. M IN M AX .0532 .0688 1 .35 1 .75 .0040 .0098 0 .10 0 .25 B .014 .018 0 .36 0 .46 C .0 075 .0 098 0 .19 0.25 D .1 89 .1 96 4 .80 4.98 E .150 .157 3 .81 3 .99 e1 A M IL LIM E T E R S MAX A1 e θ IN C H E S M IN .050 B A S IC 1.2 7 B A S IC .025 B A S IC 0.6 35 B A S IC H .2 284 .2 440 K .011 .019 0 .28 5 .80 0 .48 6.20 L 0 .16 .050 0 .41 1.27 θ 0° 8° 0° 8° R E CO M M E ND E D F O O TP R IN T 0 .72 (.02 8 ) 8X 6 .46 ( .25 5 ) 1 .78 (.07 0) 8X 1.27 ( .0 50 ) 3X SO-8 Part Marking www.irf.com 7 IRF7807V SO-8 Tape and Reel T E R M IN A L N UM B E R 1 1 2 .3 ( .4 8 4 ) 1 1 .7 ( .4 6 1 ) 8 .1 ( .31 8 ) 7 .9 ( .31 2 ) F E E D D IRE C T IO N NOTES: 1 . C O N T R O L L IN G D IM E N S IO N : M IL L IM E T E R . 2 . A L L D IM E N S IO N S A R E S H O W N IN M IL L IM E T E R S (IN C H E S ). 3 . O U T L IN E C O N F O R M S T O E IA -4 8 1 & E IA -5 4 1 . 3 30 .00 ( 12 .9 9 2 ) M A X. 1 4.4 0 ( .5 6 6 ) 1 2.4 0 ( .4 8 8 ) N O TES : 1 . CO N T R O L L IN G DIM E N S IO N : M IL L IME T E R . 2 . O UT L IN E C O N F O R M S T O E IA -4 8 1 & E IA -54 1 . 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. 3/01 8 www.irf.com