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Step 1: Connect the Board
Aux 12VDC supply
Electronic/resistive load
(0W-4400W)
High-voltage
AC power supply
+ –
N PE L
Important Operating Guidelines
The TDTTP4000W066C is for evaluation purposes only and is not intended to be a
nished product and does not include all protection features found in commercial
power supplies. Additional warnings to keep in mind:
gAn isolated AC source should be used as input. An isolated lab bench-grade
power supply or the included AUX DC supply should also be used for the 12V DC
power supply. Float the oscilloscope by using an isolated oscilloscope or by
disabling the PE (Protective Earth) pin in the power plug. Float the current probe
power supply (if any) by disabling the PE pin in the power plug.
gUse a resistive load only. The totem-pole PFC kit can work at zero load with burst
mode and the output voltage will be swinging between 375V and 385V during
burst mode.
gThe evaluation board is not fully-tested at large load steps. DO NOT apply a very
large step in the load (>2000W) when it is running.
gDO NOT manually probe the waveforms when the board is running. Set up
probing before powering up the demo board.
gThe auxiliary VDC supply must be 12V. The evaluation board will not work under
10V or over 15V VDC, for example.
gDO NOT touch any part of the evaluation board when it is running.
gWhen plugging the control cards into the socket, make sure the control cards are
fully pushed down with a clicking sound.
gIf the evaluation circuit goes into protection mode it will work as a diode bridge by
shutting down all PWM functions. Recycle the bias power supply to reset the DSP
and exit protection mode.
gDO NOT use a passive probe to measure control circuit signals and power circuit
signals at the same time. GND1 and AGND are not the same ground.
gTo get clean VGS of the low side GaN FET, it is not recommended to measure the
VDS at the same time.
gIt is not recommended to use a passive voltage probe for VDS and VGS
measurements while simultaneously using a dierential voltage probe for VIN
measurements, unless the dierential probe has very good dv/dt immunity.