AD7708/AD7718
Table XI. Registers—Quick Reference Guide
Register Name
Communications
Type
Size
Write Only 8 Bits
Power-On/Reset
Default Value
Not Applicable
CR7
WEN
CR6
R/W
CR5
0(0)
CR4 CR3 CR2 CR1 CR0
0(0) A3(0) A2(0) A1(0) A0(0)
Function
All operations to other registers are initiated through
the Communications Register. This controls whether
subsequent operations are read or write operations
and also selects the register for that subsequent
operation.
Status Register
MSB
Read Only 8 Bits
00 Hex
LSB
Provides status information on conversions, calibra-
tions and error conditions.
RDY 0
CAL
0
ERR
0
0 LOCK
Mode Register
Read/Write 8 Bits
00 Hex
MSB
CHOP NEGBUF REFSEL CHCON OSCPD MD2
MD1
LSB
MD0
Controls functions such as mode of operation, chan-
nel configuration, oscillator operation in power-down.
Control Register
MSB
CH3 CH2
Read/Write 8 Bits
CH1 CH0 U/B
RN2
07 Hex
LSB
RN1 RN0
I/O Control Register Read/Write 8 Bits
MSB
0
0 P2DIR P1DIR 0
00 Hex
LSB
0 P2DAT P1DAT
ADC (ADCCON)
This register is used to select the active channel
input, configure the operating input range, and select
unipolar or bipolar operation.
I/O (IOCON)
This register is used to control and configure the
I/O port.
Filter Register
Read/Write 8 Bits
45 Hex
MSB
LSB
SF7 SF6 SF5 SF4 SF3 SF2 SF1 SF0
This register determines the amount of averaging
performed by the sinc filter and consequently deter-
mines the data update rate of the AD7708/AD7718.
The filter register determines the update rate for
operation with CHOP enabled and CHOP disabled.
AD7718 ADC (DATA)
Data Register
Read Only 24 Bits
AD7708 (DATA)
Data Register
Read Only 16 Bits
000000 Hex
0000 Hex
Provides the most up-to-date conversion result for
the selected channel on the AD7718.
Provides the most up-to-date conversion result for
the selected channel on the AD7708.
REV. 0
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