Wurth Elektronik MDC901-EVKHB, Technical Manual

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MDC901-EVBHB Rev2021Jan5 MinDCet NV www.mindcet.com
Attention: Please refer to Evaluation Kit Important Notice on page 20 Page 11
Power Down & Disconnect Procedure
1. Slowly power down Vbus voltage back to zero and turn off
2. Shut down the PWM function generator
3. Wait at least 5 minutes (with fan on) or 10 minutes (without fan assembly installed) after operation
for EVB to fully de-energize and cool down
4. Shut down low voltage power supply
5. Disconnect coaxial cable
6. Disconnect the power cables from high voltage supply (with supply off)
7. Disconnect the input supply (Vin) from low voltage power supply (supply is off)
8. Disconnect cables from EVB as desired (EVB can fit into storage container with cables still attached)
Essential Rules for Operation

Organize a safe environment to minimize the risk of an electric shock or fire.

Prepare your measurements by checking the graphs and calculating the expected values (see EVB
Operation Conditions)

Never leave the setup unattended

Never disable the external PWM while Vbus is high

Immediately switch off Vbus when safety limits are exceeded

Measuring the temperature of the chip and board is a highly recommended safety feature

The Vbus input voltage should never exceed 100V including ringing!
Helpful Information

The converter exemplifies the best performance in the 100kHz to 1MHz switching frequency range

A 0% or 100% duty cycle are non-switching situations of conversion

Perform tests first without the heat sink/fan assembly heat sink as removal of the heat sink after
installation may damage the thermal adhesive

Automatic dead-time is conservative and results in a higher power loss compared to a well-tuned
manual dead time

Manual dead time requires user verification by oscilloscope measurements

Powering down Vbus with an active load current may de-energize quicker as the capacitors are
drained
Dead Time Control Conditions
The MDC901 has different built-in dead time control options for optimizing device performance for high
efficiency.
Automatic Dead time
The default jumper positions described in the Default State column of the Input Pins table provides the
configuration for automatic dead time. This mode will monitor the gate voltages of HS respectively LS
switches, to guarantee a break-before-make operation of HS and LS GaN transistor. In this condition the
dead time is ensured, but cannot be controlled, and is longer than what can be achieved in manual dead
time mode.