Visible to Intel only — GUID: mif1686149481644
Ixiasoft
Visible to Intel only — GUID: mif1686149481644
Ixiasoft
5.1. Signal Sensing in Sigma-Delta
Sigma-delta modulators on the power board model convert analog signals to a one-wire digital bitstream. The design demodulates or filters the bitstream in the FPGA. The FPGA uses two types of sigma-delta filter IP in the FPGA, ADC modules and DC link modules, each with different scaling and offset.
The design downloads and filters all sigma delta inputs in parallel so no skew exists between the samples that it feeds to the software application.
Each ADC type has a different input and output ranges with the corresponding 'C' data type.
ADC Type | Count Range | C Data type |
Sigma-delta ADC | -32768…+32767 | Signed 16-bit |
Sigma-delta DC link | 0…+32767 | Signed 16-bit |
Position feedback samples are scaled to a 23 bit unsigned integer, for consistency across all encoder types supported by this and previous Drive-on-Chip designs.
Feedback Quantity | Sigma Delta Interface IP | Sigma Delta Scaling for Tandem Motion Power Board |
---|---|---|
Motor phase voltages | ADC interface | 545 counts/V |
Motor input voltage | DC Link interface | 545 counts/V |
Motor phase currents | ADC interface | 1024 counts/A |