AD7322 Analog Devices, AD7322 Datasheet - Page 25

• 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

SEQUENCER OPERATION
The AD7322 can be configured to convert a sequence of
consecutive channels (see Figure 44). This sequence begins by
converting on Channel 0 and ends with a final channel selected
by Bit ADD0 in the control register. To operate the AD7322 in
this mode, set Seq1 to 1 and Seq2 to 0, and then select the final
channel in the sequence by programming Bit ADD0 in the
control register.
CS
CS
CS
CS
DIN: WRITE BIT = 0 OR DIN LINE HELD LOW TO CONTINUE TO
DOUT: CONVERSION RESULT FROM CHANNEL 0, RANGE AS
DIN: WRITE TO CONTROL REGISTER TO SELECT THE FINAL
DOUT: CONVERSION RESULT FROM CHANNEL1, RANGE AS
CHANNEL IN THE CONSECUTIVE SEQUENCE, SET Seq1 = 1
DIN: WRITE TO RANGE REGISTER TO SELECT THE RANGE
AND Seq2 = 0. SELECT OUTPUT CODING FOR SEQUENCE.
DIN: WRITE BIT = 0 OR DIN LINE HELD LOW TO CONTINUE
CS
DOUT: CONVERSION RESULT FROM CHANNEL 0, ± 10V
THROUGH SEQUENCE OF CONSECUTIVE CHANNELS.
DOUT: CONVERSION RESULT FROM CHANNEL 0,
RANGE SELECTED IN RANGE REGISTER 1,
CONVERT THROUGH THE SEQUENCE OF
FOR THE ANALOG INPUT CHANNELS.
Figure 44. Flowchart for Consecutive Sequence of Channels
SELECTED IN RANGE REGISTER.
SELECTED IN RANGE REGISTER.
FROM CHANNEL IN SEQUENCE.
RANGE, SINGLE-ENDED MODE.
SEQUENCE, Seq1 = 0, Seq2 = 0.
DOUT: CONVERSION RESULT
CONSECUTIVE CHANNELS.
DIN: WRITE TO CONTROL
REGISTER TO STOP THE
SINGLE-ENDED MODE.
A SEQUENCE.
POWER ON.
STOPPING
Rev. A | Page 25 of 36
When the control register is configured to operate the AD7322
in this mode, the DIN line can be held low, or the write bit can
be set to 0. To return to traditional multichannel operation, a
write to the control register to set Seq1 to 0 and Seq2 to 0 is
necessary.
When Seq1 and Seq2 are both set to 0, or when both are set to 1,
the AD7322 is configured to operate in traditional multichannel
mode, where a write to Channel Address Bit ADD0 in the control
register selects the next channel for conversion.
ON CONSECUTIVE SEQUENCE
CONTINUOUSLY CONVERT
OF CHANNELS.
DIN TIED LOW/WRITE BIT = 0.
AD7322