AD7490BCPZ datasheet(16/29 Pages) AD

16 / 29 page

Data Sheet

AD7490

Rev. D | Page 15 of 28

Figure 14 shows how a sequence of consecutive channels can be

converted on without having to program the Shadow register or

write to the part on each serial transfer. Again, to exit this mode

of operation and revert back to the normal mode of operation

of a multichannel ADC (as outlined in Figure 12), ensure that

the WRITE = 1 and SEQ = SHADOW = 0 on the next serial

transfer.

CONTINUOUSLY CONVERTS ON THE

SELECTED SEQUENCE OF CHANNELS BUT

WILL ALLOW RANGE, CODING, AND SO ON,

TO CHANGE IN THE CONTROL REGISTER

WITHOUT INTERRUPTING THE SEQUENCE

PROVIDED, SEQ = 1, SHADOW = 0

DUMMY CONVERSIONS

DIN = ALL 1s

DIN: WRITE TO CONTROL REGISTER,

WRITE BIT = 1,

SELECT CODING, RANGE, AND POWER MODE

SELECT CHANNEL ADD3 TO ADD0 FOR

CONVERSION,

SEQ = 1 SHADOW = 1

DOUT: CONVERSION RESULT FROM

CHANNEL 0

CONTINUOUSLY CONVERTS ON A

CONSECUTIVE SEQUENCE OF CHANNELS

FROM CHANNEL 0 UP TO AND INCLUDING

THE PREVIOUSLY SELECTED ADD3 TO ADD0

IN THE CONTROL REGISTER

WRITE BIT = 1,

SEQ = 1,

SHADOW = 0

POWER ON

WRITE

BIT = 0

WRITE BIT = 1,

SEQ = 1,

SHADOW = 0

Figure 14. SEQ Bit = 1, SHADOW Bit = 1 Flowchart

AD7490BCPZ Datasheet(PDF) 16 Page - Analog Devices