I saw yesterday in the "tang teacher speak electric motor control of the" mentioned, gate drive chip using bootstrap circuit, teacher speak the bypass capacitor of the power source is ten times the bootstrap capacitance,
But today I look at the EG2104 chip manuals, found the sample circuit, the relationship between the two, in turn, are so confused which is correct? Who is the bigger?

CodePudding user response:

In principle, the bypass capacitors and bootstrap capacitance have no relation, size is mainly to consider its circuit time constant is appropriate; You this circuit, for example, bootstrap capacitance C2, OUT during the period of high level, capacitance stored power needed to fully meet Q1 driving power, and during OUT low, want to be charged to the 12 v to C2, from this point of view of C2 capacity; And the bypass capacitor C1 main filter out high frequency, voltage stability mainly depends on the electrolysis, capacity is actually, effect shall be adjusted in practice