Texas Instruments LMG352 EVM-04 Series, Руководство пользователя

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WARNING
Do NOT turn on the device at the absolute maximum voltage. TI recommends to start the device at
or below 520 V. Slowly increase the input voltage and monitor the VSW to ensure the peak voltage
does not exceed the absolute maximum rating of 650 V.
7.3 Test Results
In this test example, a synchronous buck converter operation is implemented. The input voltage is 400V, and the
output voltage is 200V with 50% duty cycle. With the heatsink-version EVM, the inductor current goes to 20A in
this test, and an output power of 4-kW is achieved. The continuous operation waveform is shown in
Figure 7-4 .
The slew-rate is set to highest by connecting the Rdrv pin to ground. From the experimental result shown in
Figure 7-5 , a turn-on voltage slew-rate of 148 V/ns is observed at 400V/20A switching conditions.
Low-Side
PWM (5V/div)
Switch-node
Voltage (100V/div)
Load Current
(10A/div)
Figure 7-4. Continuous Buck Operation at 4 kW
Low-Side
PWM (5V/div)
Switch-node
Voltage (100V/div)
Load Current
(10A/div)
Slew Rate: 148V/ns
Figure 7-5. Fast Slew Rate at 400V/20A Switching Conditions
The turn-on slew-rate of the device can be easily adjusted (from 30V/ns to 150V/ns) by changing the Rdrv
resistance values. This is also verified from the test results shown in
Figure 7-6 to Figure 7-9 . The adjustable
slew-rate feature provides the customer a flexibility to adapt the device’s switching speed in different
applications.
www.ti.com Test Procedure When Paired With LMG342X-BB-EVM
SNOU178A – OCTOBER 2020 – REVISED FEBRUARY 2021
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LMG352XEVM-04X User Guide 17
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