AD7329 Analog Devices, AD7329 Datasheet - Page 30

• Manufacturer Part Number: AD7329
• Description: 1 MSPS , 8-Channel, Software Selectable True Bipolar Input, 12-Bit Plus Sign A/D Converter
• Manufacturer: Analog Devices

Specifications of AD7329

• Resolution (bits): 13bit
• # Chan: 8
• 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),Uni 10V
• Adc Architecture: SAR
• Pkg Type: SOP

AD7329
If a change to one of the range registers is required during a
sequence, it is necessary to first stop the sequence by writing to
the control register and setting SEQ1 to 0 and SEQ2 to 0. Next,
write to the range register to change the required range. The
previously selected sequence should then be initiated again by
writing to the control register and setting SEQ1 to 0 and SEQ2
to 1. The ADC converts the first channel in the sequence.
The AD7329 can be configured to convert a sequence of
consecutive channels (see Figure 49). This sequence begins by
converting on Channel 0 and ends with a final channel as
selected by Bit ADD2 to Bit ADD0 in the control register. In
this configuration, there is no need for a write to the sequence
register. To operate the AD7329 in this mode, set SEQ1 to 1 and
CS
CS
CS
CS
CS
DIN: WRITE TO RANGE REGISTER 1 TO SELECT THE RANGE
DIN: WRITE TO RANGE REGISTER 2 TO SELECT THE RANGE
DIN: WRITE TO CONTROL REGISTER TO SELECT THE FINAL
CHANNEL IN THE CONSECUTIVE SEQUENCE, SET SEQ1 = 1
AND SEQ2 = 0. SELECT OUTPUT CODING FOR SEQUENCE.
DIN: WRITE BIT = 0 OR DIN LINE HELD LOW TO CONTINUE
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,
DOUT: CONVERSION RESULT FROM CHANNEL 0,
DOUT: CONVERSION RESULT FROM CHANNEL 0,
DOUT: CONVERSION RESULT FROM CHANNEL 1,
TO CONVERT THROUGH THE SEQUENCE OF
RANGE SELECTED IN RANGE REGISTER 1,
RANGE SELECTED IN RANGE REGISTER 1,
RANGE SELECTED IN RANGE REGISTER 1.
RANGE SELECTED IN RANGE REGISTER 1.
Figure 49. Flowchart for Consecutive Sequence of Channels
FOR ANALOG INPUT CHANNELS.
FOR ANALOG INPUT CHANNELS.
SEQUENCE, SEQ1 = 0, SEQ2 = 0.
FROM CHANNEL IN SEQUENCE.
RANGE, SINGLE-ENDED MODE.
DOUT: CONVERSION RESULT
CONSECUTIVE CHANNELS.
DIN: WRITE TO CONTROL
REGISTER TO STOP THE
SINGLE-ENDED MODE.
SINGLE-ENDED MODE.
A SEQUENCE.
POWER ON.
STOP
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SEQ2 to 0 in the control register, and then select the final channel
in the sequence by programming Bit ADD2 to Bit ADD0 in the
control register.
After the control register is configured to operate the AD7329
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 to 1, the AD7329 is
configured to operate in traditional multichannel mode, where
a write to Channel Address Bit ADD2 to 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.