Datasheet
MAX1020/MAX1022/MAX1057/MAX1058
10-Bit, Multichannel ADCs/DACs with FIFO,
Temperature Sensing, and GPIO Ports
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Table 5. Setup Register*
BIT NAME BIT FUNCTION
— 7 (MSB) Set to zero to select setup register.
— 6 Set to one to select setup register.
CKSEL1 5 Clock mode and CNVST configuration; resets to one 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.
Table 5a. Clock Modes (see the
Clock Mode
section)
CKSEL1 CKSEL0 CONVERSION CLOCK ACQUISITION/SAMPLING CNVST CONFIGURATION
0 0 Internal Internally timed. CNVST
0 1 Internal Externally timed by CNVST. CNVST
1 0 Internal Internally timed. AIN15/AIN11/AIN7
1 1 External (3.6MHz max) Externally timed by SCLK. AIN15/AIN11/AIN7
Table 5b. Clock Modes 00, 01, and 10
REFSEL1 REFSEL0
VOLTAGE
REFERENCE
OVERRIDE
CONDITIONS
AUTOSHUTDOWN
REF2
CONFIGURATION
AIN
Inter nal r efer ence tur ns off after scan i s com p l ete. If
i nter nal r efer ence i s tur ned off, ther e i s a p r og r am m ed
d el ay of 218 i nter nal - conver si on cl ock cycl es.
00
Internal (DAC
and ADC)
Temperature
Internal reference required. There is a programmed
delay of 244 internal-conversion clock cycles for the
internal reference to settle after wake-up.
AIN14/AIN10/AIN6
AIN Internal reference not used.
01
External single-
ended (REF1
for DAC and
REF2 for ADC)
Temperature
Internal reference required. There is a programmed
delay of 244 internal-conversion clock cycles for the
internal reference to settle after wake-up.
REF2
AIN
Default reference mode. Internal reference turns off
after scan is complete. If internal reference is turned
off, there is a programmed delay of 218 internal-
conversion clock cycles.
10
Internal (ADC)
and external
REF1 (DAC)
Temperature
Internal reference required. There is a programmed
delay of 244 internal-conversion clock cycles for the
internal reference to settle after wake-up.
AIN14/AIN10/AIN6
AIN Internal reference not used.
11
External
differential
(ADC), external
REF1 (DAC)
Temperature
Internal reference required. There is a programmed
delay of 244 internal-conversion clock cycles for the
internal reference to settle after wake-up.
REF2
*
See below for bit details.