PMP21943: LM5170

Hi Tsvetan,

Is this a 12V source that you want to use to charge a 4V battery system? What is the desired maximum output voltage and current that you want from this charger for this application?

Best Regards,

Matthew

Hi Matthew,

The tester will only service single cells (3.65V/304A) at this input voltage and current. The purpose is to format each cell before inclusion and into the composition of the entire battery under the control of the BMS.

Best regards,

Tsvetan

Hi Tsvetan,

Does this need to have automotive qualified parts? Does not seem like the LM5170 is the most cost effective choice with discrete FETs is the best choice for this low voltage/high current application.

Best Regards,

Matthew

I don't care about the automotive temperature range; let it be the industrial one. From the element base, I only care about the IGBT module. You can offer me any solution, as long as it is not one of the software ones (TMS320F28P65x, for example).

Hi Tsvetan,

I am connecting you to an engineer who will be able to provide more expertise in this recommendation.

Best Regards,

Matthew

Hi Matthew,

Do you have any problem with my case?

Best regards,

Tsvetan

Hello Tsvetan,

Thanks for being patient with the delay in response.

I don't think the BQ25756E will be the best solution here. The BQ25756E can only deliver a maximum charge current of 20A. It's going to be very difficult to build a battery charger that can charge LiFePO4 batteries at 300A. I think you'll need a lot of discrete parts to build the battery charger.

Could you use a design similar to this reference design? https://www.ti.com/lit/ug/tidubm6/tidubm6.pdf

This is a 48V to 12V converter that can output 133A. I think the topology should be similar when going from 12V to 3.6V.

Let me know if you are going to use a discrete solution or if the BQ25756E will work for your application.

Best Regards,
Ethan Galloway

Hi Ethan,

Hi Ethan,

I changed my idea and took the TIDA-00195 as a sample design for a phosphate battery charger. Can I reduce the input voltage from 1100 to 12 volts and use it as a working one? Is it possible to program the Piccolo LaunchPad LAUNCHXL-F28027 to function as a charger controller? This design is especially suitable for me, since I have IGBT modules for 450A.

Best regards,

Tsvetan

Hello Tsvetan,

Thanks for being patient with this. I'm not an expert high current IGBT modules. Let me loop in the experts on isolated gate drivers who might be able to help you out better.

Best Regards,
Ethan Galloway

Hello Ethan,

I understand, I'll wait of course.

Best regards,

Tsvetan Ginin

Hi Sean,

Thank you very much for your attention to my question. Yes, I really don't need an isolated driver for the IGBT module. The tester parameters should be as follows:

Operating modes: Cyclic mode (defined as full discharge and charge) / Single charge mode / Single discharge mode

Charge cut-off voltage: 3.65 - 4.2V, set by you

Charge current: 3 - 300A, set by you

Discharge cut-off voltage: 2 - 2.9V, set by you

Discharge current: 3 - 300A, set by you

Charge mode: Constant current and constant voltage

Discharge mode: Constant current discharge (IGBT module)

Display parameters: operating time / temperature / voltage / current / capacity / curve

Voltage accuracy: 0.1% (calibrated)

Current accuracy: 0.2% (calibrated)

Capacity error: Discharge ±1.5%, Charging ±2%

Power Dissipation Heat: Intelligent PWM speed control of fan or water pump(at a temperature higher than 80 degrees Celsius)

Protection function: Reverse polarity protection, high temperature protection

Best regards,

Tsvetan

Hi Seon,

I find your suggestions interesting and I will certainly consider them. Can I rely on your expert opinion regarding the future schematic diagram of the tester? Or is it better to close the discussion now?

Best regards,

Tsvetan

I apologize for the annoying mistake: Sean, not "Seon"