Battery Management Systems (BMS)
Battery stacks in power inverters and electric/hybrid vehicles need to be monitored for optimization and cell protection, and data from the ADCs needs to be isolated from the controller bus.
This circuit illustrates measurement of the voltage of each battery cell of a DC to AC inverter:
The last isolation stage is a full 300 V above the controller ground, so the isolator is subject to 300 V between inputs and outputs.
Endurance voltage, the voltage that can be applied between isolator inputs and outputs indefinitely, is 800 Vrms, or 1,130 Vpeak for IsoLoop Isolators. This allows isolation of battery stacks with more than 200 3.6 V cells. BMS ICs can consolidate data for six to 12 cells, which reduces the number of isolation channels required but not the isolation voltage.
Compared to other isolators, IsoLoop Isolators minimize signal distortion with 10 ns typical propagation delay and 100 ps jitter. Reduce board space with up
to five channels in 0.15" or 0.3"-wide SOICs.
Explaining Isolator Endurance Voltage
4-, and 5-Channel Isolator selector
Four-Channel Isolator data
Five-Channel Isolator data sheet
Bulletin: Isolator Endurance Voltage
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