EVAL-AD7934-6CB AD [Analog Devices], EVAL-AD7934-6CB Datasheet - Page 14

• Manufacturer Part Number: EVAL-AD7934-6CB
• Description: 4-Channel, 625 kSPS, 12-Bit Parallel ADC with a Sequencer
• Manufacturer: AD [Analog Devices]

AD7934-6
SEQUENCER OPERATION
The configuration of the SEQ0 and SEQ1 bits in the control register allow the user to use the sequencer function. Table 10 outlines the
two sequencer modes of operation.
Table 10. Sequence Selection Modes
SEQ0
0
0
1
1
NOTE ON WRITING TO THE CONTROL REGISTER TO PROGRAM THE SEQUENCER
The AD7933 and AD7934 need 13 full CLKIN periods to perform a conversion. If the ADC does not receive the full 13 CLKIN periods,
the conversion is aborted. If a conversion is aborted after applying 12.5 CLKIN periods to the ADC, ensure that a rising edge of CONVST
or a falling edge of CLKIN is applied to the part before writing to the control register to program the sequencer. If these conditions are not
met, then the sequencer is not in the correct state to handle being reprogrammed for another sequence of conversions. As a result, the
performance of the converter is not guaranteed.
SEQ1
0
1
0
1
Sequence Type
This configuration is selected when the sequence function is not used. The analog input channel selected on each
individual conversion is determined by the contents of the channel address bits, ADD1 and ADD0, in each prior write
operation. This mode of operation reflects the normal operation of a multichannel ADC, without the sequencer function
being used, where each write to the AD7934-6 selects the next channel for conversion.
Not used.
Not used.
This configuration is used in conjunction with the channel address bits, ADD1 and ADD0, to program continuous
conversions on a consecutive sequence of channels from Channel 0 to a selected final channel, as determined by
the channel address bits in the control register. When in differential or pseudo-differential mode, inverse channels
(for example, VIN1, VIN0) are not converted in this mode.
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