MAX1027_09 Datasheet, PDF (18/23 Pages) Maxim Integrated Products – 10-Bit 300ksps ADCs with FIFO, Temp Sensor, Internal Reference

10-Bit 300ksps ADCs with FIFO,
Temp Sensor, Internal Reference
CNVST
(ACQUISITION1)
CS
(ACQUISITION2)
SCLK
(CONVERSION1)
(CONVERSION2)
DOUT
MSB1
LSB1
EOC
REQUEST MULTIPLE CONVERSIONS BY SETTING CNVST LOW FOR EACH CONVERSION. X = DON'T CARE.
Figure 5. Clock Mode 01
MSB2
DIN
CS
SCLK
(CONVERSION BYTE)
(UP TO 514 INTERNALLY CLOCKED ACQUISITIONS AND CONVERSIONS)
DOUT
MSB1
LSB1
MSB2
EOC
THE CONVERSION BYTE BEGINS THE ACQUISITION. CNVST IS NOT REQUIRED. X = DON'T CARE.
Figure 6. Clock Mode 10
Internally Timed Acquisitions and
Conversions Using the Serial Interface
Performing Conversions in Clock Mode 10
In clock mode 10, the wake up, acquisition, conversion,
and shutdown sequences are initiated by writing an
input data byte to the conversion register, and are per-
formed automatically using the internal oscillator. This
is the default clock mode upon power-up. See Figure 6
for clock mode 10 timing.
Initiate a scan by writing a byte to the conversion regis-
ter. The MAX1027/MAX1029/MAX1031 then power up,
scan all requested channels, store the results in the
FIFO, and shut down. After the scan is complete, EOC
is pulled low and the results are available in the FIFO. If
a temperature measurement is requested, the tempera-
ture result precedes all other FIFO results. EOC stays
low until CS is pulled low again.
Externally Clocked Acquisitions and
Conversions Using the Serial Interface
Performing Conversions in Clock Mode 11
In clock mode 11, acquisitions and conversions are ini-
tiated by writing to the conversion register and are per-
formed one at a time using the SCLK as the conversion
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