8.4.9.1 Read-Data-Continuous Mode

In the read-data-continuous mode, conversion data are read from the ADC without need for the read command. This mode is the default mode at power-on. This mode is also enabled by the RDATAC command. When DRDY goes low, indicating that new data are available, the MSB of data is placed on DOUT, as shown in Figure 61. The data are read (latched) by the user on the rising edges of SCLK. At the first falling edge of SCLK, DRDY returns high. After 32 bits of data have been read, further SCLK transitions cause DOUT to go low. If desired, the read operation may be stopped at 24 bits. The entire data shift operation must be completed within four CLK periods before DRDY falls again or the data may be corrupted.

When a SDATAC command is issued, the DRDY output is blocked but the ADS1284 continues conversions. In stop continuous mode, the data is read by command.

1. DOUT is in tristate when CS is high. CS can be tied low. See Figure 1 for CS low to valid DOUT propagation time.

Figure 61. Read Data Continuous