Preliminary Technical Data

AD7322

Reference used for each channel will be the value written to the Ref bit during the last write to the Control

Register.

3,2

Seq1/Seq2

The Sequence 1 and Sequence 2 bits are used to control the operation of the Sequencer. See Table 8

14,12,11,1

ZERO

A zero must be written to this bit to ensure correct operation of the AD7322.

Table 9. Analog Input Configuration Selection

Channel Address Bit

Mode1 =1, Mode0 = 1

Mode1 = 1, Mode0 =0

Mode1 = 0, Mode0 =1

Mode1 =0, Mode0 =0

1 Pseudo Differential I/p

1Fully Differential i/p

Not Allowed

Two-Single Ended i/ps

ADD0

Vin+

Vin-

Vin+

Vin-

Vin+

Vin-

0

Vin0

Vin1

Vin0

Vin1

Vin0

AGND

1

Vin0

Vin1

Vin0

Vin1

Vin1

AGND

Table 10. Power Mode Selection

PM1

PM0

Description

1

1

Full Shutdown Mode,

In this mode all internal circuitry on the

AD7322 is powered down. Information in the Control register is

retained when the AD7322 is in Full Shutdown Mode.

1

0

Auto Shutdown Mode,

The AD7322 will enter Full Shut down

at the end of each conversion when the control register is

updated. All internal circuitry is powered down in Full

Shutdown.

0

1

Auto Standby Mode,

In this mode all internal circuitry is

powered down excluding the internal Reference. The AD7322

will enter Auto Standby Mode at the end of the Conversion after

the control register is updated.

0

0

Normal Mode,

All internal Circuitry is powered up at all times.

Table 11. Sequencer Selection

Seq1

Seq2

Sequence type

0

0

The Channel Sequencer is not used. The Analog Channel selected by programming the ADD0 bit in the

Control Register selects the next channel for conversion.

1

0

This Configuration is used in conjunction with the Channel Address Bit in the Control Register. Provided that

the channel Address bit is 1, the ADC will convert firstly on channel 0 then channel 1 and will repeat this

sequence until the Seq bits are changed in the Control Register.

1

1

The Channel Sequencer is not used. The Analog Channel selected by programming the ADD0 bit in the

Control Register selects the next channel for conversion.

Rev. PrE | Page 13 of 18