Datasheet

IRF7821PbF
www.irf.com 7
D.U.T.
V
DS
I
D
I
G
3mA
V
GS
.3µF
50KΩ
.2µF
12V
Current Regulator
Same Type as D.U.T.
Current Sampling Resistors
+
-
Fig 16. Gate Charge Test Circuit
Fig 15. Peak Diode Recovery dv/dt Test Circuit for N-Channel
HEXFET
®
Power MOSFETs
Circuit Layout Considerations
• Low Stray Inductance
• Ground Plane
• Low Leakage Inductance
Current Transformer
P.W.
Period
di/dt
Diode Recovery
dv/dt
Ripple ≤ 5%
Body Diode Forward Drop
Re-Applied
Voltage
Reverse
Recovery
Current
Body Diode Forward
Current
V
GS
=10V
V
DD
I
SD
Driver Gate Drive
D.U.T. I
SD
Waveform
D.U.T. V
DS
Waveform
Inductor Curent
D =
P. W .
Period
* V
GS
= 5V for Logic Level Devices
*
+
-
+
+
+
-
-
-



R
G
V
DD
• 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
D.U.T

Fig 17. Gate Charge Waveform
Vds
Vgs
Id
Vgs(th)
Qgs1
Qgs2 Qgd Qgodr