Datasheet

Data Sheet AD7294
Rev. H | Page 27 of 48
REGISTER SETTING
The AD7294 contains internal registers (see Figure 49) that
store conversion results, high and low conversion limits, and
information to configure and control the device.
ADDRESS
POINTER
REGISTER
SERIAL BUS INTERFACE
SDA
SCL
DATA
COMMAND
REGISTER
RESULT
REGISTER
DAC
REGISTERS
T
SENSE
RESULT
REGISTERS × 3
T
SENSE
OFFSET
REGISTERS × 2
ALERT
REGISTERS × 3
CONFIGURATION
REGISTER
POWER-DOWN
REGISTER
HYSTERESIS
REGISTER
DATA
HIGH
/
DATA
LOW
REGISTERS × 18
CHANNEL
SEQUENCE
REGISTER
05747-039
Figure 49. AD7294 Register Structure
Each data register has an address to which the address pointer
register points when communicating with it. The command
register is the only register that is a write-only register; the rest
are read/write registers.
ADDRESS POINTER REGISTER
The address pointer register is an 8-bit register, in which the
6 LSBs are used as pointer bits to store an address that points
to one of the AD7294 data registers, see Table 9.
Table 9. AD7294 Register Address
Address in Hex Registers (R is Read/W is Write)
00 Command Register (W)
01 Result Register (R)/DAC
A
Value (W)
02 T
SENSE
1 Result (R)/DAC
B
Value (W)
03 T
SENSE
2 Result (R)/DAC
C
Value (W)
04 T
SENSE
INT Result (R)/DAC
D
Value (W)
05 Alert Register A (R/W)
06 Alert Register B (R/W)
07 Alert Register C (R/W)
08 Channel Sequence Register (R/W)
09 Configuration Register (R/W)
0A Power-Down Register (R/W)
0B DATA
LOW
Register V
IN
0 (R/W)
0C DATA
HIGH
Register V
IN
0 (R/W)
0D Hysteresis Register V
IN
0 (R/W)
0E DATA
LOW
Register V
IN
1 (R/W)
0F DATA
HIGH
Register V
IN
1 (R/W)
10 Hysteresis Register V
IN
1 (R/W)
11 DATA
LOW
Register, V
IN
2 (R/W)
12 DATA
HIGH
Register V
IN
2 (R/W)
13 Hysteresis Register V
IN
2 (R/W)
14 DATA
LOW
Register V
IN
3 (R/W)
15 DATA
HIGH
Register V
IN
3 (R/W)
16 Hysteresis Register V
IN
3 (R/W)
17 DATA
LOW
Register I
SENSE
1 (R/W)
18 DATA
HIGH
Register I
SENSE
1 (R/W)
19 Hysteresis Register I
SENSE
1 (R/W)
1A DATA
LOW
Register I
SENSE
2 (R/W)
1B DATA
HIGH
Register I
SENSE
2 (R/W)
1C Hysteresis Register I
SENSE
2 (R/W)
1D DATA
LOW
Register T
SENSE
1 (R/W)
1E DATA
HIGH
Register T
SENSE
1 (R/W)
1F Hysteresis Register T
SENSE
1 (R/W)
20 DATA
LOW
Register T
SENSE
2 (R/W)
21 DATA
HIGH
Register T
SENSE
2 (R/W)
22 Hysteresis Register T
SENSE
2 (R/W)
23 DATA
LOW
Register T
SENSE
INT (R/W)
24 DATA
HIGH
Register T
SENSE
INT (R/W)
25 Hysteresis Register T
SENSE
INT (R/W)
26 T
SENSE
1 Offset Register (R/W)
27 T
SENSE
2 Offset Register (R/W)
40 Factory Test Mode
41 Factory Test Mode