ADS7945: ADC input channel selection

SY Yoon

Genius 3381 points

Part Number: ADS7945

Hi,

I have some questions.

1. Channel Selection

CH SEL can be toggled at any time during the window specified in Figure 77 of datasheet.

But TI recommend to select the desired channel after the first SCLK rising edge and before the second SCLK rising edge.

Is this recommendation mandatory?

2. Could I get some driver source or example code related in AD7945?

3. I want to display 2's complement result on LCD. Any examples?

over 3 years ago

0 Cynthia over 3 years ago

TI__Mastermind 25020 points

Hello,

1. A recommendation is not mandatory, but note that outside the recommended area, it can cause erroneous output code because the device might see unsettled analog input. Note that the second rising edge of SCLK is not the only option, anywhere during the conversion phase will be acceptable and not result in settling issues (after the first rising edge of SCLK)

2 & 3. Any supportive collateral available is listed in the design and development section of the device product page ~click here~

Regards

Cynthia

0 SY Yoon over 3 years ago in reply to Cynthia

Genius 3381 points

Hi,

Can I pre-select a channel when CS is high?

+1 Cynthia over 3 years ago in reply to SY Yoon

TI__Mastermind 25020 points

No, while CS is high is not a time to change channel_select.

Note that when CS is high the device is likely in acquisition phase, which should be avoided to do any type of changes.

Regards

Cynthia

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ADS7945: ADC input channel selection