Note: These products are no longer in production. Please refer to the Current Sensors currently in production.
The Silicon Labs Si850x/1x is an inductive current sensor based on a Rogowski coil, a form of coupled inductor. The sensor consists of an embedded metal slug embedded in the package that induces and voltage equal Lmdi/dt into a pick-up coil located on a nearby silicon die. The induced is processed by an analog integrator, which "reconstructs" the current signal sensed by the metal slug. The signal is then temperature compensated and adjusted for offset, then sent to the output pin by way of a buffer. The output swing is nominally 0 to 2 V, but can be higher provided the signal does not clip from too low a VDD. The Si850x/1x requires resetting after every measurement, which is executed using gate control signals already in the system and without external components.