Mixed signal microchip PAC1861 series

programmablepower measurementpower

Overview
The PAC1861 is a single-channel 65 V power, current and energy monitor integrating a bus-voltage monitor and current-sense amplifier into a single 12-bit ADC front end. It performs on-chip power calculations and accumulates proportional power results to support long-term energy measurement (integration periods up to one year or longer). Bus voltage, sense resistor voltage and accumulated energy data are available in registers for retrieval by a system host or embedded controller. The device supports high-side and low-side current sensing and bi-directional measurement, with configurable sampling and integration controlled via SMBus or I2C. Real-time auto-calibration and adjustable averaging minimize offset and noise; no external input filters are required.

Key Features

• High-side and low-side single-channel power monitor
• 100 mV full-scale sense range (configurable to 50 mV)
• External sense resistor defines full-scale current
• 16-bit effective sense current resolution via digital processing
• Bus-voltage monitoring with 0 V to 65 V full-scale range
• ~1% power measurement accuracy across wide dynamic range
• Real-time offset auto-calibration for voltage and current
• On-chip 32-bit accumulator for energy measurement
• Programmable sampling rates: 8, 64, 256, 1024, 4096, 8192
• Supply voltage: 2.7 V to 5.5 V; I/O tolerance 1.62 V to 5.5 V
• I2C Fast Mode Plus (1 Mbps), SMBus 3.1 and High-Speed (3.4 Mbps) support
• Alert outputs for over/under voltage, overcurrent and overpower (up to two pins)
• Coulomb-counting mode available via accumulator selection
• Designed for bi-directional current sensing

Technical specifications

• Model: PAC1861
• Manufacturer: Microchip Technology
• Bus voltage full-scale range: 0 V to 65 V
• Sense voltage full-scale range: 100 mV (configurable to 50 mV) via external sense resistor
• On-chip ADC: single 12-bit ADC
• Sense current resolution: 16-bit (digital processing)
• Power measurement accuracy: ~1% over wide dynamic range
• Energy accumulation: on-chip 32-bit accumulator for proportional power results
• Programmable sampling rates: 8, 64, 256, 1024, 4096, 8192 samples
• Supply voltage (VCC): 2.7 V to 5.5 V
• I/O / interface voltage range: 1.62 V to 5.5 V (I2C/SMBus and digital I/O)
• I2C/SMBus compatibility: SMBus 3.1; I2C Fast Mode Plus (1 Mbps); High-Speed Mode (3.4 Mbps)
• Alert capabilities: over/under voltage, overcurrent, overpower detection; up to two alert pins
• Topology: supports high-side and low-side current sensing; bi-directional measurement
• Noise reduction: adjustable averaging; no external input filters required
• Datasheet: DS20007175 (PAC1861 Single-Channel Power Monitor with Accumulator, 65V FSR)
• Typical applications: power monitoring, energy metering, battery and system power management