PAC1921 High-Side Power and Current Monitoring
Created: Dec 21, 2016
No description available.
The process of monitoring current in a circuit is a safety precaution to avoid overload and to know the true current and power consumption. The reference design is a high side power and current monitoring featuring the functionality of PAC1921. The PAC1921 is a firm power-monitoring device with a configurable analog output that can present power, current or voltage. This IC is designed for power measurement and diagnostic systems that cannot allow latency when performing high-speed power management.
The reference design is an evaluation board for PAC1921, which contains a current-sensing circuit and precision bus voltage measurement circuit. The PAC1921 has a 1% accurate power measurement that measures and cancels the zero offset from the input pins. It is also designed to monitor power rails from 0-32V with a full-scale capability of 100mV across the sense resistor. The board has two modes of function: demo mode and sys mode. In demo mode, the board monitors an on-board power source. While sys mode measures an external power source. Demo mode uses 100mV constant-current source that is provided using a +5V USB as the supply. Parallel sense resistors are provided to convert the current to a corresponding voltage for the PAC1921 to read at the SENSE+ and SENSE- inputs. A 5 milliohm (1% tolerance) sense resistor, connected between J1 and J2, is provided on-board the PAC1921 evaluation board to measure the system current.
The PAC1921 can also be used in applications like diagnostic equipment, servers, power supplies, industrial and power management systems, and desktop computers.