ADS1274
ADS1278
SBAS367F –JUNE 2007–REVISED FEBRUARY 2011
www.ti.com
ADS1274/78
ADS1274/78
U2
U1
SYNC
CLK
SYNC
SYNC
DRDY
DRDY Output from Device 1
DOUT from Devices 1 and 2
CLK
DIN
CLK
DIN
DOUT1
DOUT1
SCLK
SCLK
SCLK
NOTE: The number of chained devices is limited by the SCLK rate and device mode.
Figure 81. Daisy-Chaining of Two Devices, SPI Protocol (FORMAT[2:0] = 000 or 001)
SCLK
1
2
25
26
49
50
73
74
97
98
193
194
217
218
385
386
DOUT1
CH1, U1
CH2, U1
CH3, U1
CH4, U1
CH5, U1
CH1, U2
CH2, U2
DIN2
DRDY
(SPI)
FSYNC
(Frame-Sync)
Figure 82. Daisy-Chain Data Format of Figure 81 (ADS1278 shown)
SYNC
CLK
Serial Data
Devices 3 and 4
ADS1274/78
ADS1274/78
ADS1274/78
ADS1274/78
U4
U3
U2
U1
SYNC
SYNC
SYNC
SYNC
CLK
DIN
CLK
CLK
DIN
CLK
Serial Data
DOUT1
DOUT1
DOUT1
DIN
DOUT1
DIN
Devices 1 and 2
FSYNC
SCLK
FSYNC
SCLK
FSYNC
SCLK
FSYNC
SCLK
SCLK
FSYNC
NOTE: The number of chained devices is limited by the SCLK rate and device mode.
Figure 83. Segmented DOUT Daisy-Chain, Frame-Sync Protocol (FORMAT[2:0] = 011 or 100)
34
Submit Documentation Feedback
© 2007–2011, Texas Instruments Incorporated
Product Folder Link(s): ADS1274 ADS1278
TI [ TEXAS INSTRUMENTS ]
