ADS1262 START pin DRDY pin and SPI pins

Mickey Zhang

Genius 12080 points

Other Parts Discussed in Thread: ADS1262

Hi Sir,

The customer has some issues about ADS1262 .

If the customer uses 4--wires SPI of ADS1262 to communicate with MCU, can START pin and DRDY pin unconnect with MCU?

If START pin and DRDY pin can unconnect with MCU,how to deal with these two pins? pull up or floating?

Thanks,

Best Regards,

over 9 years ago

0 Christopher Hall over 9 years ago

TI__Mastermind 44680 points

Hi Mickey,

The START and /DRDY pins do no need to be used in order to communicate with the ADS1262.

If unused...
- /DRDY may be left floating, since this is a digital output.
- The START pin should be tied to GND, so that the "START1" and "STOP1" SPI commands can be used to control conversions.

For data ready indication, the customer may monitor the DOUT/nDRDY pin, or poll the STATUS byte to determine when the ADC conversion has completed.

Best Regards,
Chris

0 Mickey Zhang over 9 years ago in reply to Christopher Hall

TI__Genius 12080 points

Hi Christopher,
I see. Thanks for your reply.

0 Mickey Zhang over 9 years ago in reply to Christopher Hall

TI__Genius 12080 points

Hi Christopher,

If START pin is always low, will this suspend the last continuous conversion ?
Thanks,

0 Christopher Hall over 9 years ago in reply to Mickey Zhang

TI__Mastermind 44680 points

Hi Mickey,

When the START pin is low, you must use the SPI commands (START1/STOP1) to control ADC conversions. Sending the START1 is effectively the same thing as setting the START pin high. You shouldn't have any issues if the START pin is tied low.

However, I made the recommendation to tie START low because this avoids contentions between the START pin and commands. Normally the START pin takes precedence, so setting it high could cause the ADC to ignore the STOP1 command.

Best Regards,
Chris

0 Mickey Zhang over 9 years ago in reply to Christopher Hall

TI__Genius 12080 points

Hi Christopher,
Thanks. I will tell the customer.

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ADS1262 START pin DRDY pin and SPI pins