MDC901-EVBHB Rev2021Jan5
MinDCet NV
Attention: Please refer to Evaluation Kit Important Notice on page 20
Page 13
The input pins jumper positions for TgapOn<2:4>, and TgapOff<2:4> determine the respective total dead
time according to the following equations:
𝑇𝑔𝑎𝑝𝑂𝑛 = 2.8𝑛𝑠 + 𝑇𝑔𝑎𝑝𝑂𝑛2 + 𝑇𝑔𝑎𝑝𝑂𝑛3 + 𝑇𝑔𝑎𝑝𝑂𝑛4
𝑇𝑔𝑎𝑝𝑂𝑓𝑓 = 2.8𝑛𝑠 + 𝑇𝑔𝑎𝑝𝑂𝑓𝑓2 + 𝑇𝑔𝑎𝑝𝑂𝑓𝑓3 + 𝑇𝑔𝑎𝑝𝑂𝑓𝑓4
Where Table 1Table 2 defines the amount of dead time for each pin input.
Table 2: Dead time adjustment variable values
The listed TgapOn/Off dead time adjustment values are theoretical and can differ to experimental results.
For the example in Figure 6, the placed jumpers result in a dead time of TgapOn=2.8ns + 9ns=11.8ns and
TgapOff=11.8ns.
Temperature Measurements
In addition to the on-board temperature sensor of the MDC901 IC, the evaluation board offers a second
temperature measurement point in the proximity of the MDC901 IC and GaN HEMTs. The board
temperature sensor is a NTC thermistor placed just below the MDC901, serving as a confirmation point of
the IC temperature and provides insight into the GaN half-bridge temperature.
For the board temperature, measure the resistance (R) of the 4k7 thermistor with a high impedance
(>100MΩ) DMM between output pins 2 and 3.
The following equation converts the measured resistance value R to temperature:
Pin State
TgapOn2 /TgapOff2 TgapOn3/TgapOff3
TgapOn4/TgaOff4
+5 / open
9ns
18ns
36ns
GND
0ns
0ns
0ns
𝑇𝑏𝑜𝑎𝑟𝑑 =
𝑇
0
𝛽
25/85
𝑇
0
ln (
𝑅
𝑅
0
) + 𝛽
25/85
[°C]
𝑅
0
= 298.15K
𝑇
0
= 4700
Ω
𝛽
25/85
= 3830
Figure 7: Board and internal IC temperature sensing measurement
