Broadcom ACPL-0873 3-channel digital filter

A 3-channel digital filter designed specifically for Second Order Sigma Delta Modulators in voltage and current sensing. Each input channel can receive an independent Sigma-Delta (Σ-Δ) modulator bit stream. The bit streams are processed by 3 individually programmable digital decimation filters. Features of the digital filter include 4 decimation ratios for Sinc2 mode and 3 decimation ratios for Sinc3 mode, offset calibration and fast over-range detection. Synchronization of inputs from 3 channels is done internally by the filter alignment.

Key features

• 3 Independently Programmable Digital Filters
• Synchronizing sampling time
• Offset Calibration
• SPI-compatible Interface

Additional features

• Direct Interface between Isolated Sigma-Delta Modulator and MCU/DSP
• Fast Over-range Detection
• Channel 1 MCLK clock detection
• Programmable Input Configuration
• Compact surface mount QFN-20 5mmx5mm·       
• Operating Temperature -40°C to 125°C
• SPI clock frequency up to 25MHz
• Modulator clock frequency MCLK up to 25MHz

Applications

• Electric motor phase and rail current sensing
• DC/DC converter current sensing
• AC-DC charger current sensing
• Battery current sensing
• General voltage or current sensing