ADS7263: REFIO pin voltage

K.Hamamoto

Guru 12155 points

Part Number: ADS7263

I have some question about REFIOx pin.

The register setting of the customer are below;

Config register : 0xD060

REFDAC1:0x07FF

REFDAC2:0x07FF

REFCM:0x0000

At this setting , do we need to input the some voltage to REIOx pin?

It does not convert as expected when they input the some voltage to CMx pin. However it does convert as expected when they input 2.5V to REFIOx pin.

At the default setting of REFCM, the common-mode voltage is set by CMx pin. Also at the default setting of REFDACx, the reference voltage is set by external voltage of REFIOx. So that , we need to supply to both of CMx and REFIOx.

(We can not leave the REFIOx pin open in case of this configuration setting as above.)

Is my understanding correct?

Please let me know if my understanding is not correct.

Regards,

Koji Hamamoto

over 6 years ago

0 Evan Sawyer over 6 years ago

TI__Expert 3175 points

Hamamoto-san,

We are looking into this and will get back to you.

0 Evan Sawyer over 6 years ago in reply to Evan Sawyer

TI__Expert 3175 points

Hamamoto-san,

Yes, your understanding is correct.

By writing 07FFh to both the REFDAC1 and REFDAC2 registers, the internal voltage reference is disconnected. Thus an external voltage reference must be connected to the device for it to properly convert.

0 K.Hamamoto over 6 years ago in reply to Evan Sawyer

Guru 12155 points

Hi Evan-san,

Thank you for your support.

I understood.
(We need to connect the external voltage reference to REFIOx pin when the REFDACx pin is set to external reference whatever REFCM are.)

Regards,
Koji Hamamoto

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ADS7263: REFIO pin voltage