Part Number: UCC21750QDWEVM-025
Hi Team,
Based on the Datasheet of UCC21750, the AIN pin can be used for DC-link voltage and temperature monitoring. From my understanding, the internal current source is used to generate a voltage across the internal/external NTC for temperature measurement (Rt=V/I), whilst the dc-link voltage measurement is more of based on the voltage divider, which is the voltage across R42. Then for temperature monitoring purpose, can I remove R42 in 'UCC217XX Family Driving and Protecting SiC and IGBT Power Modules and Transistors', Fig. 2, Block 4?
If this is not the case, during the dc-link voltage monitoring, rather than measuring the divider R42 from the dc-link voltage (Vdc*[R42/(R42+R33+R34+R35+R36+R37)]), there is also a voltage across R42 from the internal current source, V= I*R = 200e-6x6.19e3 =1.238V. How to determine the dc-link voltage from VAIN then?
Many thanks,
Weichi