Signal conditioning chip for position sensors

iC-Haus in Germany has developed a highly integrated circuit for signal conditioning and high-speed sine-to-digital conversion for magnetic or optical position sensors.

The iC-NQE from iC-Haus provides a connection for 80 MSPS sine/digital conversion for resolutions up to 16 bits per input period. It also integrates a temperature sensor with a programmable alarm threshold for operational monitoring and the required cable drivers on the output side, which saves valuable space in the sensor read head.

The iC-NQE can also be used universally on the receiver side as a 32-bit counter module for quadrature signals up to 500 kHz, on IPC interface cards, in drive inverters or in a programmable logic controller (PLC).

The converter is driven by high precision programmable amplifiers that accept small to large differential sensor signals from 30 mV to 3 V. Primary signal errors can be compensated to a residual signal error of less than 0.1% using analogue corrections.

The non-linearity of the sensor can be corrected by digitally adjusting the transfer function in the converter if necessary. The converter circuit bases on the well-proven vector tracking principle for virtually latency-free angle tracking. An optional digital position filter can also be enabled for noise and interference suppression.

The iC-NQE operates at 3.3 V or 5 V and is supplied in a 32-pin QFN with an edge length of 5 x 5 mm. The chip contains the RS-422 drivers for outputting quadrature signals with up to 16,384 AB pulses plus zero signal, or UVW commutation signals for BLDC motors with up to 32 pole pairs, as well as the necessary transceiver for a serial BiSS or SSI interface. Embedded applications with a microcontroller can use SPI or I2C as the data interface.

A compatible version of iC-NQE is also planned for position sensors in industrial applications with 20-pin TSSOP, enabling performance upgrades without PCB changes.