AD7280A

Lithium Ion Battery Monitoring System AD7280A FEATURES 12-bit ADC, 1 μs per channel conversion time 6 analog input channels, common-mode range 0.5 V to 27.5 V 6 auxiliary ADC inputs ±1.6 mV cell voltage accuracy On-chip voltage regulator Cell balancing interface Daisy-chain interface Internal reference: ±3 ppm/oC 1.8 μA power-down current High input impedance Serial interface with alert function 1 SPI interface for up to 48 channels CRC protection on read and write commands On-chip registers for channel sequencing VDD operating range: 8 V to 30 V Temperature range: −40°C to +105°C 48-lead LQFP Qualified for automotive applications APPLICATIONS Lithium ion battery monitoring Electric and hybrid electric vehicles Power supply backup Power tools GENERAL DESCRIPTION The AD7280A1 contains all the functions required for generalpurpose 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 V...