ADS127L01: Frame-Sync Slave Interface

Hello Victor,

In frame sync slave mode, the host processor provides the SCLK and FSYNC clock to each of the devices in parallel.  For cascade mode, you simply read each DOUT pin separately, or in parallel.  From the ADC's point of view, there is no difference between a single device or multiple devices when using cascade mode; the timing is the same.

For daisy chain, the host again supplies SCLK and FSYNC clocks to each of the devices.  In this case, there is only one DOUT connection to the host.  Each frame now consists of all channels shifted out on the same DOUT.

The specific timing requirements for this mode can be found in Tables 6.10 and 6.11 of the datasheet, as well as Figures 4 and 5.  There is additional information in Figures 107 and Figures 108 for daisy chain frame sync, and Figure 104 for cascaded frame sync.  Also, please note that in frame sync mode, both the /CS pin and DIN pin should be tied to DGND.

Regards,
Keith Nicholas
Precision ADC Applications