Here’s a current sense circuit collection from Linear Technology. The collection is organized by application type and for each one there are a few example circuits. High side, low side, level shifting, high and low voltage, fault sensing, etc:
Sensing and/or controlling current flow is a fundamental requirement in many electronics systems, and the techniques to do so are as diverse as the applications them-selves. This Application Note compiles solutions to current sensing problems and organizes the solutions by general application type. These circuits have been culled from a variety of Linear Technology documents.
Thanks Jim! Via the comments.
How does this compare in price comparing to these http://www.allegromicro.com/Products/Current-Sensor-ICs.aspx . The Allegro parts are not so flexible when it comes to range you want to sense on, but can make life easier if board-space is tight, and you need isolation.
the link is broken, here is the new one http://cds.linear.com/docs/en/application-note/an105fa.pdf