具有信號隔離和功率隔離的鋰離子電池組監(jiān)控器

　　具有信號隔離和功率隔離的鋰離子電池組監(jiān)控器

　　電路功能與效益

　　鋰離子（Li Ion）電池堆中含有大量的單個電池，必須對其進(jìn)行正確的監(jiān)控，以提高電池的效率，延長電池的使用壽命。在圖1中所示的行為作為主要監(jiān)測電池管理控制器提供精確的測量數(shù)據(jù)的電路通道的ad7280a設(shè)備（BMC）。的ad7280a內(nèi)部包含±3 ppm的參考，讓一個±1.6 mV的電池電壓測量精度。ADC分辨率為12位，允許在7微米內(nèi)轉(zhuǎn)換多達(dá)48個單元。

　　的ad7280a，駐留在電池管理系統(tǒng)（BMS），高壓側(cè)界面菊花鏈，允許最多八ad7280as被堆放在一起，允許48的鋰離子電池電壓進(jìn)行監(jiān)測。堆棧中的相鄰ad7280as可以直接溝通，向上和向下的數(shù)據(jù)傳遞不需要堆棧分離。在堆棧的底部ad7280a主設(shè)備采用SPI接口與BMC溝通，而只有在這一點(diǎn)上，高壓電隔離是為了保護(hù)系統(tǒng)低壓側(cè)。的數(shù)字隔離器，隔離器ADuM1201 adum5401集成DC/DC變換器結(jié)合在一個緊湊的和成本有效的解決方案，提供所需的六通道隔離。

　　Circuit description

　　The AD7280A daisy chain obtains its power from the battery cells it monitors. The ADuM5401 includes an integrated DC-to-DC converter which is used to power the high voltage side of the ADuM1201， provide the VDRIVE supply to the AD7280A SPI interface， and provide the power-down （PD） signal to the AD7280A daisy chain circuit. If the +5 V supply is pulled low on the low voltage side of the BMS， the isolators and the chain of AD7280A’s will power down. Likewise， if the PD signal from the BMC is taken low， the low voltage supply to the ADuM5401 routed through the ADG849 switch is driven low and also provides a hardware power down of the isolators and the chain of AD7280A devices.