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Electronics => Power/Renewable Energy/EV's => Topic started by: Faringdon on June 26, 2022, 12:18:51 pm

Title: Fast NPN's for gate drive transformer?
Post by: Faringdon on June 26, 2022, 12:18:51 pm
Hi,
Would you agree, that Q3 and Q2 in the attached (LTspice and jpeg attached) would best be BC849 rather than MMBT2904? -Because Transition frequency is higher.
What would be the best transistor to use here?

MMBT3904
https://www.mouser.co.uk/datasheet/2/308/1/PZT3904_D-2319825.pdf (https://www.mouser.co.uk/datasheet/2/308/1/PZT3904_D-2319825.pdf)

BC849
https://assets.nexperia.com/documents/data-sheet/BC849_BC850.pdf (https://assets.nexperia.com/documents/data-sheet/BC849_BC850.pdf)

Do you also agree that for Q3 and Q2, one should seek amongst low current BJTs (eg <100mA)...because they will be quicker?...since their doping regions are less densely doped?