TPS62133: on the same 12V power supply with a DRV8870?

R Peters

Part Number: TPS62133
Other Parts Discussed in Thread: DRV8870,

On our PCB we plan to use the TPS61233 to generate a stable 5V (1A load) and motor driver DRV8870 (max. 2A load) sharing the same 12V input. Is there a risk that load changes on the DRV8870 lead to noise on the 5V output?

over 5 years ago

0 Gerold Dhanabalan - High Performance Radar over 5 years ago

TI__Genius 14455 points

If there are two TPS62133 devices each powering the 5V load and the DRV8870 separately, the noise due to the DRV8870 will likely not couple into the main 12V supply.

However, there is a possibility that if the two TPS62133 are switching at slightly different frequencies, the difference between the two Fsw, can appear as beat frequency (low frequency noise) on the 12V supply.

If the 5V load is sensitive to noise, it is a good idea to have an LDO infront.

Regards,

Gerold

0 R Peters over 5 years ago in reply to Gerold Dhanabalan - High Performance Radar

Prodigy 20 points

Hi Gerold,

Thank you for your advice, I'll add an LDO to the design.

Regards,

Roderick

Power management

Power management forum

TPS62133: on the same 12V power supply with a DRV8870?