OPA2333-Q1: OPA2333 question

Songzhen Guo

Part Number: OPA2333-Q1
Other Parts Discussed in Thread: TINA-TI, OPA2188-Q1, TLV2186, OPA2333

Hi Expert,

OPA2333-Q1 was used to sensing battery voltage in BMS system. It's a design for Hydrogen energy battery. The application is show below:

Part 1 is Battery system; Part 2 is sensing part. Those two parts are reference two different GND.(GND1 and GND2).

Can the amplifier work well?
Those two parts are reference different GND. Is there any risk?

Best Regards

Songzhen Guo

over 4 years ago

0 Marek Lis over 4 years ago

TI__Guru 63770 points

Guo,

Yes, such BMS system can work but the supplies for each op amps must be bootstrapped (for example, using at least 20 Zener diodes) and the outputs must be level-shifted as shown using U100_LS op amp so DAC powered from 5V single supply can monitor the voltage.

I have attached here TINA-TI circuit schematic for your convenience.

8233.OPA2333 BMS System.TSC

0 Songzhen Guo over 4 years ago in reply to Marek Lis

TI__Intellectual 2840 points

Hi Marek,

Thank you so much for your support. This is very useful.

If customer want to wide input voltage input(±5V), it mean the supply voltage of amplifier need come to ±5V. Could you recommend a amplifier for this application? Thanks.

Best Regards

Songzhen Guo

0 Marek Lis over 4 years ago in reply to Songzhen Guo

TI__Guru 63770 points

Guo,

For +/-5V input range, you could NOT use OPA2333 because of its max total supply of 5.5V (or +/-2.75V). Thus, for 10V total supply the best alternative would be to use TLV2186 but it is not Q1 automotive qualified. If you must have Q1 qualification, then the closest would be OPA2188-Q1.

Of course, in order to implement your BMS monitoring scheme With 10V supply, you would now have to use Zener diodes with 10V breakdown voltage instead of 5V I used in OPA2333 implementation.

0 Marek Lis over 4 years ago in reply to Marek Lis

TI__Guru 63770 points

Guo,

Below please find a simpler implementation of the BMS monitoring scheme - there is no need for higher supply op amp since all of the readings in the battery stack must be read by DAC powered by 5V single supply.

2134.OPA2333 BMS System.TSC

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OPA2333-Q1: OPA2333 question