hi
i wanna make current sensing circuit for my 24 V bldc motor driver. i wanna use high side current shunt measurements as AN894 mentioned, but still confused about calculating the components value (Rsense, R1 and R2 for the op amp).

my power inverter circuit is attached


anyone help please..

 

Your main DC supply is only 24V so you may not need a high voltage type op-amp.

You need to state a couple of design goals.

Do you want current sensing on all output phases or just one?
What is the per-phase peak load current?
What output voltage range do you require from the current sensing circuit - for the given peak load current range?
How much power loss are you willing to tolerate in the sensing resistor(s)?

 

Your main DC supply is only 24V so you may not need a high voltage type op-amp.

You need to state a couple of design goals.

Do you want current sensing on all output phases or just one?

i want current sensing on all phases

What is the per-phase peak load current?

max. motor input current is about 3 A

What output voltage range do you require from the current sensing circuit - for the given peak load current range?

it will be read by ADC of microcontroller, so i need 0-5v

How much power loss are you willing to tolerate in the sensing resistor(s)?

need help/suggestion also for this