AD7280A锂离子电池监测系统

　　The AD7280A1 contains all the functions required for general-purpose monitoring of stacked lithium ion batteries as used in hybrid electric vehicles， battery backup applications， and power tools. The part has multiplexed cell voltage and auxiliary ADC measurement channels for up to six cells of battery management. An internal ±3 ppm/°C reference is provided that allows a cell voltage accuracy of ±1.6 mV. The ADC resolution is 12 bits and allows conversion of up to 48 cells within 7 μs.

　　The AD7280A operates from a single VDD supply that has a range of 8 V to 30 V （with an absolute maximum rating of

　　33 V）。 The part provides six differential analog input channels to accommodate large common-mode signals across the full VDD range. Each channel allows an input signal range， VIN（+） − VIN（−）， of 1 V to 5 V. The input pins assume a series stack of six cells. In addition， the part includes six auxiliary ADC input channels that can be used for temperature measurement or system diagnostics.

　　The AD7280A includes on-chip registers that allow a sequence of channel measurements to be programmed to suit the application requirements.

　　The AD7280A also includes a dynamic alert function that can detect whether the cell voltages or auxiliary ADC inputs exceed an upper or lower limit defined by the user. The AD7280A has cell balancing interface outputs designed to control external FET transistors to allow discharging of individual cells.

　　The AD7280A includes a built-in self-test feature that internally applies a known voltage to the ADC inputs.

　　A daisy-chain interface allows up to eight parts to be stacked without the need for individual device isolation.

　　The AD7280A requires only one supply pin that accepts 6.9 mA under normal operation while converting at 1 MSPS.

　　All this functionality is provided in a 48-lead LQFP package operating over a temperature range of −40°C to +105°C.