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Details, datasheet, quote on part number:IRF7807ATR
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Datasheet text preview:
PD 91747C
IRF7807/IRF7807A
HEXFET® Chip-Set for DC-DC Converters
· · · · N Channel Application Specific MOSFETs Ideal for Mobile DC-DC Converters Low Conduction Losses Low Switching Losses
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Description These new devices employ advanced HEXFET Power MOSFET technology to achieve an unprecedented b a l a n c e of on-resistance and gate charge. The reduced conduction and switching losses make them ideal for high efficiency DC-DC Converters that power the latest generation of mobile microprocessors. A pair of IRF7807 devices provides the best cost/ performance solution for system voltages, such as 3.3V and 5V.
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Device Features IRF7807 IRF7807A Vds 30V 30V Rds(on) 25m 25m Qg 17nC 17nC Qsw 5.2nC Qoss 16.8nC 16.8nC
Absolute Maximum Ratings Parameter Drain-Source Voltage Gate-Source Voltage Continuous Drain or Source Current (VGS 4.5V) Pulsed Drain Current Power Dissipation 25°C 70°C Junction & Storage Temperature Range Continuous Source Current (Body Diode) Pulsed source Current TJ, TSTG IS ISM 2.5 66 25°C 70°C IDM PD Symbol VDS VGS ID 8.3 6.6 66 2.5 1.6 55 to 150 2.5 66 °C A IRF7807 30 ±12 8.3 6.6 66 W A IRF7807A Units V
Thermal Resistance Parameter Maximum Junction-to-Ambient
RJA
Max. 50
Units °C/W
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10/10/00
IRF7807/IRF7807A
Electrical Characteristics Parameter Drain-to-Source Breakdown Voltage* Static Drain-Source on Resistance* Gate Threshold Voltage* Drain-Source Leakage Current* V(BR)DSS RDS(on) VGS(th) IDSS 1.0 30 150 I GSS Qg Q gs1 Q gs2 Qg d Q SW Q oss Rg td(on) tr td (off) tf 12 2.1 0.76 2.9 3.66 14 1.2 12 17 25 6 5.2 16.8 ±100 17 12 2.1 0.76 2.9 3.66 14 1.2 12 17 25 6 ns 16.8 VDD = 16V ID = 7A Rg = 2 VGS = 4.5V Resistive Load Conditions IS = 7A, VGS = 0V di/dt = 700A/µs VDS = 16V, VGS = 0V, IS = 7A di/dt = 700A/µs (with 10BQ040) VDS = 16V, VGS = 0V, IS = 7A VDS = 16V, VGS = 0 nC IRF7807 Min Typ Max 30 17 25 1.0 30 150 ±100 17 nA IRF7807A Min Typ Max Units 30 17 25 V m V µA Conditions VGS = 0V, ID = 250µA VGS = 4.5V, ID = 7A VDS = VGS, ID = 250µA VDS = 24V, VGS = 0 VDS = 24V, VGS = 0, Tj = 100°C VGS = ±12V VGS = 5V, ID = 7A VDS = 16V, ID = 7A
Gate-Source Leakage Current* Total Gate Charge* Pre-Vth Gate-Source Charge Post-Vth Gate-Source Charge Gate to Drain Charge Switch Charge* (Qgs2 + Qgd) Output Charge* Gate Resistance Turn-on Delay Time Rise Time Turn-off Delay Time Fall Time
Source-Drain Rating & Characteristics Parameter Diode Forward Voltage* Reverse Recovery Charge Reverse Recovery Charge (with Parallel Schotkky) Notes:
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Min VSD Q rr Qrr(s)
Typ Max 1.2 80 50
Min
Typ Max Units 1.2 80 50 V nC
Repetitive rating; pulse width limited by max. junction temperature. Pulse width 300 µs; duty cycle 2%. When mounted on 1 inch square copper board, t < 10 sec. Typ = measured - Qoss Devices are 100% tested to these parameters.
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IRF7807/IRF7807A
Power MOSFET Selection for 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;
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Drain Current
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Gate Voltage t2 VGTH t0 t1 t3
QGS1
QGS2
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QGD
Ploss = Pconduction+ Pswitching+ Pdrive+ Poutput
This can be expanded and approximated by;
Drain Voltage
Figure 1: Typical MOSFET switching waveform
Ploss = (Irms 2 × Rds( on ) ) Q + I × gd × Vin × ig + (Qg × Vg × f ) Q + oss × 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 (non-linear) capacitance's Cds and Cdg when multiplied by the power supply input buss voltage.
Synchronous FET
Q f + I × gs 2 × Vin × ig
f
The power loss equation for Q2 is approximated by;
Ploss = Pconduction + Pdrive + Po*utput Ploss = Irms × Rds(on) + (Qg × Vg × f )
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Q Q + oss × Vin × f + ( rr × Vin × f ) 2
*dissipated primarily in Q1.
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