AD7322 Analog Devices, AD7322 Datasheet - Page 21

• Manufacturer Part Number: AD7322
• Description: Software Selectable True Bipolar Input, 2-Channel, 12-Bit Plus Sign ADC
• Manufacturer: Analog Devices

Specifications of AD7322

• Resolution (bits): 13bit
• # Chan: 2
• Sample Rate: 1MSPS
• Interface: Ser,SPI
• Analog Input Type: Diff-Bip,Diff-Uni,SE-Uni
• Ain Range: Bip (Vref),Bip (Vref) x 2,Bip (Vref) x 4,Bip 10V,Bip 2.5V,Bip 5.0V,Uni (Vref) x 4,Uni 10V
• Adc Architecture: SAR
• Pkg Type: SOP

REGISTERS
The AD7322 has two programmable registers, the control
register and the range register. These registers are write-only
registers.
ADDRESSING REGISTERS
A serial transfer on the AD7322 consists of 16 SCLK cycles. The
three MSBs on the DIN line during the 16 SCLK transfer are
decoded to determine which register is addressed. The three
Table 8. Decoding Register Select Bit and Write Bit
Write
0
1
1
Zero
0
0
0
Register Select
X
0
1
Comment
Data on the DIN line during this serial transfer is ignored. Register contents remain unchanged.
This combination selects the control register. The subsequent 12 bits are loaded into the control register.
This combination selects the range register. The subsequent six bits are loaded into the range register.
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MSBs consist of the write bit, zero bit, and register select bit.
The register select bit is used to determine which of the two on-
board registers is selected. The write bit determines if the data
on the DIN line following the register select bit loads into the
addressed register. If the write bit is 1, the bits are loaded into
the register addressed by the register select bits. If the write bit
is 0, the data on the DIN line does not load into any register.
The zero bit must always be set to 0.
AD7322