TMS320F28P650SK: about the external adc voltage ref design

song guo

Part Number: TMS320F28P650SK
Other Parts Discussed in Thread: REF3430

Tool/software:

Dear Forum Members,

I am designing a system using the TMS320F28P650SK MCU with its internal 16-bit ADC. Currently, I plan to use the REF3430 (3.0V output) as the voltage reference. Could you please advise on the following:

1.Should I add a buffer to improve drive capability, especially if the ADC samples at high speed.

2 How to choose an OA.

3.Below is a circuit diagram, is it available or any suggestions.

Thanks!

song

8 months ago

0 Masoud Farhadi 8 months ago

TI__Expert 7270 points

Hello,

I would suggest you to this app report for designing your circuit "ADC Input Circuit Evaluation for C2000 MCUs (TINA-TI) Application Report".

Overall, we recommend an external reference when your application demands better temperature stability than the internal source. The device’s internal bandgap has a temperature coefficient, which can limit accuracy over wide temperature ranges. You can use a low-noise, low output impedance buffer between the reference and ADCREFIN. Also, add a small capacitor close to ADCREFIN for decoupling.

Best Regards,

Masoud

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28P650SK: about the external adc voltage ref design