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Rainbow Electronics MAX1230 User Manual

Page 18

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MAX1226/MAX1228/MAX1230

12-Bit 300ksps ADCs with FIFO,
Temp Sensor, Internal Reference

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Initiate a scan by writing a byte to the conversion regis-
ter. The MAX1226/MAX1228/MAX1230 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
clock. Scanning and averaging are disabled, and the
conversion result is available at DOUT during the con-
version. See Figure 7 for clock mode 11 timing.

CS

DOUT

SCLK

CNVST

EOC

(CONVERSION2)

MSB1

LSB1

MSB2

(ACQUISITION1)

(ACQUISITION2)

(CONVERSION1)

REQUEST MULTIPLE CONVERSIONS BY SETTING CNVST LOW FOR EACH CONVERSION.

Figure 5. Clock Mode 01

(UP TO 514 INTERNALLY CLOCKED ACQUISITIONS AND CONVERSIONS)

MSB1

LSB1

MSB2

(CONVERSION BYTE)

CS

DOUT

SCLK

DIN

EOC

THE CONVERSION BYTE BEGINS THE ACQUISITION. CNVST IS NOT REQUIRED.

Figure 6. Clock Mode 10