Rainbow Electronics MAX1231 - Manual (Page 14)

MAX1227/MAX1229/MAX1231
12-Bit 300ksps ADCs with FIFO,
Temp Sensor, Internal Reference
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Table 3. Setup Register*
BIT NAME BIT FUNCTION
— 7 (MSB) Set to zero to select setup register.
— 6 Set to 1 to select setup register.
CKSEL1 5 Clock mode and CNVST configuration. Resets to 1 at power-up.
CKSEL0 4 Clock mode and CNVST configuration.
REFSEL1 3 Reference mode configuration.
REFSEL0 2 Reference mode configuration.
DIFFSEL1 1 Unipolar/bipolar mode register configuration for differential mode.
DIFFSEL0 0 (LSB) Unipolar/bipolar mode register configuration for differential mode.
CKSEL1 CKSEL0 CONVERSION CLOCK ACQUISITION/SAMPLING CNVST CONFIGURATION
0 0 Internal Internally timed
CNVST
0 1 Internal Externally timed through CNVST CNVST
1 0 Internal Internally timed AIN15/11/7
1 1 External (4.8MHz max) Externally timed through SCLK AIN15/11/7
REFSEL1 REFSEL0 VOLTAGE REFERENCE AutoShutdown REF- CONFIGURATION
0 0 Internal
Reference off after scan; need
wake-up delay.
AIN14/10/6
0 1 External single ended Reference off; no wake-up delay. AIN14/10/6
1 0 Internal
Reference always on; no wake-up
delay.
AIN14/10/6
1 1 External differential Reference off; no wake-up delay. REF-
DIFFSEL1 DIFFSEL0 FUNCTION
0 0 No data follows the setup byte. Unipolar mode and bipolar mode registers remain unchanged.
0 1 No data follows the setup byte. Unipolar mode and bipolar mode registers remain unchanged.
1 0 One byte of data follows the setup byte and is written to the unipolar mode register.
1 1 One byte of data follows the setup byte and is written to the bipolar mode register.
*See below for bit details.