AN829 Datasheet, PDF (8/9 Pages) STMicroelectronics – SEMICONDUCTOR KIT FOR

AN829 APPLICATION NOTE
junction temperature to be accurately estimated:
with :
V_in = 220Vac/I_in = 8Arms
V_out = 400Vdc/R_gn = 0Ω
MOSFET+DIODE conduction losses = 10W
MOSFET+DIODE commutat. losses = .52W/kHz
with:
V_in = 120Vac/I_in = 15Arms
V_out = 400Vdc/Rgn = 0Ω
MOSFET+DIODE conduction losses = 40W
MOSFET+DIODE commutat. losses = .88W/kHz
with a gate drive resistance R_gn=102, 25% must be
added to the commutation losses.
Figure 5. Current & Voltage Recorders-
D95IN256A
INSTANTANEOUS INDUCTOR
CURRENT (2A/DIV)
CURRENT AMPLIFIER
OUTPUT (1V/DIV)
RECTIFIED MAINS
VOLTAGE(50V/DIV)
Figure 7. Average Current & Voltage-
D95IN265A
AVERAGE INDUCTOR
CURRENT 5A/DIV
RECTIFIED MAINS
VOLTAGE 50V/DIV
1msec DIV
Figure 8. Turn Off Mosfet behavior-
D95IN266A
TURN OFF DRAIN
VOLTAGE 50V/DIV(-100V offset)
VOLTAGE ERROR OUTPUT
(1V/DIV)
1msec DIV
Figure 6. Average Current & Voltage-
D95IN257A
AVERAGE INDUCTOR
CURRENT (2A/DIV)
AVERAGE CURRENT
AMPLIFIER OUTPUT
RECTIFIED MAINS
(1VDIV)
VOLTAGE (50V/DIV)
TURN OFF SOURCE
CURRENT (5A/DIV)
Figure 9. Diode Recovery Current
D95IN267A
5A/DIV
8/9
VOLTAGE ERROR
OUTPUT (1V/DIV)
1msec DIV
20nsec DIV