ADS1198: Data format and range

Arash_

Part Number: ADS1198
Other Parts Discussed in Thread: ADS1194,

Q1- In ADS1198 datasheet page 27 under Data retrieval It says output data is 24+#ch*16 bits, so for 1194 should be 24+4*16=88 bits. Should I read 88bit frames for ADS1194, or read 152bits frame but just ignore last 4 channels?

Q2- If gain is not 1, LSB weight is Vref/Gain.(2^15-1)?

Q3- In page 21 under Input Diff. Dynamic Range, it says input range is Vref/Gain, so with Vref=2.4V and Gain=6, input range is 2.4/6=400mV, but datasheet says input range is 300mV for this values. Why is that?

over 8 years ago

0 Brian Pisani over 8 years ago

TI__Mastermind 38745 points

Hello Arash,

You only need to read the first 88 bits.
Yes.
It says that the supply is "optimized for power" for a 300 mV signal. You can still measure up to +/- 400 mV with a gain of 6.

Brian

0 Arash_ over 8 years ago in reply to Brian Pisani

Prodigy 230 points

Hi Brian,
Thank you. Just wanted be sure in 1, so ADS1194 sends 152 bits for each conversion and I read only the first 88bits, or it sends 88bits for each conversion?

0 Brian Pisani over 8 years ago in reply to Arash_

TI__Mastermind 38745 points

Hey Arash,

The ADS1194 is the slave device so the number of bits it sends depends on the number of times the host toggles SCLK.

Brian

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ADS1198: Data format and range