4

dc1961af

DEMO MANUAL DC1961A

performance

DRAIN VOLTAGE OF

SYNCHRONOUS MOSFET

200mV/DIV

GATE OF SYNCHRONOUS

MOSFET, 5V/DIV

1µS/DIV

DC1961A F05

INTVCC VOLTAGE OF

LT8309, 10V/DIV

SWITCH NODE VOLTAGE

OF PRIMARY MOSFET,

50V/DIV

1mS/DIV

DC1961A F06

Figure 5. Synchronous MOSFET Drain and Gate Voltage (VIN = 48V, IOUT = 5A)

Figure 6. Output Short Circuit Waveforms (VIN = 48V)

Figure 7. Thermal Picture, 48VIN and 5AOUT (TA = 25°C, Air Flow 200LFM)

Synchronous MOSFET, 52.5°C; Primary MOSFET, 46.7°C; Transformer, 74.1°C