2 Device Operation

To better comprehend what affects measurement errors with a Hall-based current sensor like the TMCS1100, understanding how the device operates in a general sense is helpful. TMCS1100 Operation Diagram illustrates how current flows through the copper lead frame of the device. As the current flows from IN+ to IN–, a magnetic field is generated in accordance with Ampere's law. This magnetic field produces a voltage potential change on sensors located in the center of the lead frame via the Hall-effect . This potential is then scaled, sampled by the sampling integrator, and sent to the output pin of the device. Note that the positive polarity of the magnetic coupling factor as current flows from IN+ to IN– is a magnetic field generated downward into the sensor, denoted in this paper as the negative z direction.

For any given TMCS110x device, there are typically multiple sensitivity variants. For the TMCS1100, the sensitivities include 50 mV/A, 100 mV/A, 200 mV/A, and 400 mV/A. For each device, the lead frame and the Hall stage are the same for all variants within some manufacturing tolerance.