Analog Devices Inc. AD8451 Precision Analog Front-End & Controller

Analog Devices Inc. AD8451 Precision Analog Front-End & Controller is designed to test and monitor battery cells. AD8451's precision fixed gain instrumentation amplifier (IA) measures the battery charge/discharge current, and a fixed gain difference amplifier (DA) measures the battery voltage. Internal laser trimmed resistor networks set the gains for the IA and the DA, optimizing the performance of the AD8451 over the rated temperature range. The IA gain is 26 and the DA gain is 0.8. Voltages at the ISET and VSET inputs set the desired constant current (CC) and constant voltage (CV) values. AD8451's CC to CV switching is automatic and transparent to the system. 

An analog output, VCTRL, interfaces directly with the Analog Devices ADP1972 PWM controller. AD8451 simplifies designs by providing excellent accuracy, performance over temperature, flexibility with functionality, and overall reliability in a space-saving package.


  • Integrated constant current and voltage modes with automatic switchover
  • Precision voltage and current measurement
  • Integrated precision control feedback blocks
  • Precision interface to PWM or linear power converters
  • Fixed gain settings
    • 26V/V (typ) Current sense gain
    • 0.8V/V (typ) Voltage sense gain
  • Charge and discharge modes
  • Excellent AC and DC performance
  • 0.9μV/°C Maximum offset voltage drift
  • 3ppm/°C Maximum gain drift
  • >9nV/√Hz Typ. low current sense amplifier input voltage noise
  • 108dB min. Current sense CMRR
  • TTL compliant logic


  • Battery cell formation and testing
  • Battery module testing

Functional Block Diagram

Block Diagram - Analog Devices Inc. AD8451 Precision Analog Front-End & Controller
Publicado: 2014-07-14 | Atualizado: 2022-03-11