AD7992 Analog Devices, AD7992 Datasheet - Page 22

• Manufacturer Part Number: AD7992
• Description: 2-Channel, 12-Bit ADC with I2C Compatible Interface in 10-Lead MSOP
• Manufacturer: Analog Devices

Specifications of AD7992

• Resolution (bits): 12bit
• # Chan: 2
• Sample Rate: 79kSPS
• Interface: I²C/Ser 2-Wire,Ser
• Analog Input Type: SE-Uni
• Ain Range: Uni (Vref),Uni Vdd
• Adc Architecture: SAR
• Pkg Type: SOP

AD7992
WRITING TWO BYTES OF DATA TO A LIMIT
REGISTER OR HYSTERESIS REGISTER
Each of the limit registers and hysteresis registers are 12-bit
registers, so two bytes of data are required to write a value to
any one of them. Writing two bytes of data to one of these
registers consists of the serial bus write address, the chosen
limit register address written to the address pointer register,
followed by two data bytes written to the selected data register.
See Figure 27.
SDA (CONTINUED)
SCL (CONTINUED)
SDA
SCL
START BY
MASTER
MOST SIGNIFICANT DATA BYTE
9
0
1
0
1
0
1
SERIAL BUS ADDRESS BYTE
0
0
A3
0
FRAME 1
D11
A2
Figure 27. Two-Byte Write Sequence
D10
A1
Rev. 0 | Page 22 of 28
A0
D9
R/W
D8
ACK. BY
AD7992
ACK. BY
AD7992
9
9
If the master is write-addressing the AD7992, it can write to
more than one register with out re-addressing the ADC. After
the first write operation has completed for the first data register,
during the next byte, the master writes to the address pointer
byte to select the next data register for a write operation. This
eliminates the need to re-address the device in order to write to
another data register.
C4
D7
1
1
LEAST SIGNIFICANT DATA BYTE
C3
D6
ADDRESS POINTER REGISTER
C2
D5
D4
C1
FRAME 2
D3
P3
P2
D2
D1/0
P1
D0/0
P0
ACK. BY
ACK. BY
AD7992
AD7992
9
9
STOP BY
MASTER