TSC1031 Series 5.5 V 700 kHz High-Side Current Sense Amplifier SMT - SOIC-8. View topic - shunt mod via a voltage divider. Uploading the spice modle for this circuit so you can play with it a bit and change it to your liking program to view edit and simulate spice file remove the .doc extension to open it in ltspice.
ZXCT1009 Series 300 kHz 4 uA 2.5 to 20 V High-Side Current Monitor - SOT-23. Overview Product Highlight Bandwidth: 300 kHz Quiescent Current: 4 µA Supply Voltage: 2.5 to 20 V Input Current: 100 nA Zetex is a leading provider of high performance, analog semiconductor products for signal processing and power management.
LM324A Series High Gain Low Power Quad Operational Amplifier - SOIC-14.