How to use low voltage OP to sense hi-side current

Status
Not open for further replies.

xiexi

Member level 4
Joined
Jan 14, 2005
Messages
79
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Activity points
613
The VCM is 30V, but OP is low voltage 5V process. The voltage across Rs is 0.1V, so the first OP's output is about 10mv, this is too small to accept. Can anyone gives me instruction to get a small current propotional to high-side current. The speed and accuracy is important. Thanks
 

same ckt can work with diff gnd or use ct transformmer using small coil.
 

Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…