TPS2124: Battery switching primary to secondary supply

jayanthi budati

Part Number: TPS2124
Other Parts Discussed in Thread: LM74800-Q1, LM74900, LM74900-Q1

Tool/software:

Hi team,

I am looking for a design suggestion for automatic switching of battery supplies (primary to secondary) in one of our Automotive projects. The use case is that when the primary one is dead to ensure continuous power supply to the ECU. So kindly suggest a solution for the battery switching.

The primary battery supply: 24V.

The secondary battery supply: 12V

The Continuous load current: 20A.

Thanks,

Jayanthi.

over 1 year ago

0 Kunal Goel over 1 year ago

TI__Guru* 79181 points

Hi Jayanthi,

We will check on this and get back to you.

Regards

Kunal Goel

0 Shiven Dhir over 1 year ago in reply to Kunal Goel

TI__Mastermind 48475 points

Hi Jayanthi,

You can either use an ORing configuration using LM74703/4-Q1 that will switchover to 12V supply only when PS1 has fallen to 12V-11mV.

Or you can consider using LM74800-Q1 in priority power MUX configuration in which you can program the switch-over point of PS1 to PS2.

Priority Power MUX using Ideal Diodes in Automotive Zonal Modules

Regards,

Shiven Dhir

0 jayanthi budati over 1 year ago in reply to Shiven Dhir

Prodigy 90 points

Hi team,

Thank you for reply, LM74800-Q1 is suitable for our Battery Switching(Primary to Secondary)requirement, Could you please provide any schematics design files for our requirement.

Primary Battery voltage :24VDC
Secondary battery Voltage :24VVDC
Continuous Load Current :20A
Peak load current :25A

Thank you,

Jayanthi.

0 Shiven Dhir over 1 year ago in reply to jayanthi budati

TI__Mastermind 48475 points

Hi Jayanthi,

We do not a have schematic. We just provide the application diagram, and schematic can be drawn with its help.

Although we have EVMs which have schematics of standalone operation of LM74800-Q1.

LM74800 Evaluation Module: LM74800EVM-CD (Rev. A)

Regards,

Shiven Dhir

0 jayanthi budati 11 months ago in reply to Shiven Dhir

Prodigy 90 points

Hi team,

Thank you for reply, By changing the FET Voltage and current rating can we use LM74800-Q1 for our application.

below mention voltage and current rating our requirment.

Primary Battery voltage :24VDC
Secondary battery Voltage :24VVDC
Continuous Load Current :20A
Peak load current :25A

Thank you,

jayanthi.

+1 Shiven Dhir 11 months ago in reply to jayanthi budati

TI__Mastermind 48475 points

Hi Jayanthi,

LM74800-Q1 is a MOSFET Gate driver and far as the external FET can support the requirements, LM74800-Q1 can support it as well.

It is important to note that LM74800-Q1 has +70V abs-max rating and exposing any higher voltage will damage it.

Regards,

Shiven Dhir

0 jayanthi budati 11 months ago in reply to Shiven Dhir

Prodigy 90 points

Hi team,

Thank you for reply, LM74800-Q1 has two topologies one is Common Drain (CD) and another Common Source (CS), Could you please suggest which one is suitable for our application.

below mention voltage and current rating our requirement.

Primary Battery voltage :24VDC
Secondary battery Voltage :24VVDC
Continuous Load Current :20A
Peak load current :25A

Thank you,

jayanthi.

0 Shiven Dhir 11 months ago in reply to jayanthi budati

TI__Mastermind 48475 points

Hi Jayanthi,

You can use CD topology as CS is usually used when Input has transients that will violate the abs-max rating of the controller.

Regards,

Shiven Dhir

0 jayanthi budati 11 months ago in reply to Shiven Dhir

Prodigy 90 points

Hi team,

Thank you for reply, For Battery switching (primary to secondary) i have designed LM74800-Q Circuit, i have doubt when the switching time primary to secondary, is Load (MCU)Alive or Dead state.

Thank you,

jayanthi.

0 Shiven Dhir 11 months ago in reply to jayanthi budati

TI__Mastermind 48475 points

Hi Jayanthi,

Although the switching is fast enough in priority power Muxing. But the output caps have to be scaled such that the load is alive.

This is more of system level issue and not related to controller.

Regards,

Shiven Dhir

0 jayanthi budati 11 months ago in reply to Shiven Dhir

Prodigy 90 points

Hi team,

Thank you for reply, For Battery switching (primary to secondary) i am planning to use LM74800-Q Circuit,

but now i am planning shift to LM74900-Q IC, it has Additional feature Over current protection, Could you please let me know it is suitable for battery switching (primary to secondary). because LM74900 does not have VSNS pin.

thank you,

jayanthi.

0 Shiven Dhir 11 months ago in reply to jayanthi budati

TI__Mastermind 48475 points

Hi Jayanthi,

LM74900-Q1 can achieve the same.

The application diagram shows how to set it up.

Regards,

Shiven Dhir

0 jayanthi budati 11 months ago in reply to Shiven Dhir

Prodigy 90 points

Hi team,

Thank you for reply, Please let me know if you can review our schematic for LM74900-Q1. I will provide schematic mail.

Thank you,

jayanthi.

0 Shiven Dhir 11 months ago in reply to jayanthi budati

TI__Mastermind 48475 points

Hi Jayanthi,

You can send it to me in pvt. chat.

Regards,

Shiven Dhir

0 jayanthi budati 11 months ago in reply to Shiven Dhir

Prodigy 90 points

Hi team,

All the files have already been shared in your private chat. Please review them and let me know if there are any changes needed.

Thank you,
jayanthi.

0 Shiven Dhir 11 months ago in reply to jayanthi budati

TI__Mastermind 48475 points

I will get back to you by end of this week.

Regards,

Shiven Dhir

0 jayanthi budati 11 months ago in reply to Shiven Dhir

Prodigy 90 points

Shiven Dhir,

Thank you for your response.

thanks,

jayanthi.

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TPS2124: Battery switching primary to secondary supply