ADS1015-Q1: ACK by Master delay

Shinji Tsuji

Part Number: ADS1015-Q1
Other Parts Discussed in Thread: ADS1015

Hi team,

I am considering to use ADS1015-Q1's I2C communication with MCU over Serializer and Deserializer as below.

ADS1015-Q1 <--> Deserializer <- Cable(I2C signal embedded into serial signal) -> Serializer <--> MCU

There is maximum 40us delay from ADS1015 to MCU, and I am concerned if ACK by Master(MCU) delays 40us after Data output from ADS1015.

Refer to datasheet page 20 Figure15

Is there any requirement between end of ADS1015 data out to ACK by Master timing?

regards,

over 4 years ago

0 Joseph Wu over 4 years ago

TI__Guru* 92655 points

Shinji-san,

A delay of 40us from the master ACK shouldn't be a problem. From the timing requirements table, the min SCLK frequency is 10kHz, which translates to an SCLK period of 100us, which is longer than 40us.

Additionally, this device has a timeout for the I2C communication. Exceeding the timeout will reset the I2C communication. However, this timeout is about 30ms to 35ms, which is much larger than the 40us delay.

Joseph Wu

0 Shinji Tsuji over 4 years ago in reply to Joseph Wu

TI__Genius 12338 points

Hi Joseph,

Thank you for the reply.

I planned to use 400KHz clock frequency.

Is that possible to keep this frequency, or do I need to change the frequency to 10KHz to return ACK by Master?

regards,

0 Joseph Wu over 4 years ago in reply to Shinji Tsuji

TI__Guru* 92655 points

Shinji-san,

They don't need to change the clock frequency, and they can use the 400kHz clock.

The master controls SCLK and the device will be able to work with the added delay to the ACK.

Joseph Wu

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ADS1015-Q1: ACK by Master delay