General Background

A project log for "High" Bandwidth - Current Sense Amplifier

Configurable gain and bandwidth current sense amplifier. DC to 1MHz/100kHz bandwidth, at 25x/50x gain.

jesse-farrellJesse Farrell 06/04/2023 at 19:400 Comments

Single chip CSA solutions exist, but all fall short in one aspect or another. Whether it be the low bandwidth of the INA27x series, limited configurability of hall-effect options, or just part availability.

The main goal of this design is to provide a simple circuit that will work with a wide range of IC’s on the market, and can be used (or adapted) for many different applications. To accomplish this, I first found what was the most common 4-channel op-amp package. Turns out 14-TSSOP (0.173", 4.40mm Width) is one of the most common packages for in stock op-amps. To support lower spec’d devices I included some options to compensate the total offset voltage, and to compensate the offset voltage caused by op-amp bias current.

For more information see the HAB document… I’ll be keeping these logs somewhat brief, and more testing focused.