AD7912/AD7922

Rev. 0 | Page 10 of 32

PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS

GND

8

7

6

5

DOUT

1

CS

2

SCLK

3

DIN

4

AD7912/

AD7922

8-LEAD MSOP

TOP VIEW

(Not to Scale)

Figure 8. 8-Lead MSOP Pin Configuration

GND

8

7

6

5

DIN

1

SCLK

2

CS

3

DOUT

4

AD7912/

AD7922

8-LEAD TSOT

TOP VIEW

(Not to Scale)

Figure 9. 8-Lead TSOT Pin Configuration

Table 5. Pin Function Descriptions

MSOP

Pin No.

TSOT

Pin No.

Mnemonic

Function

1

4

DOUT

Data Out. Logic output. The conversion result from the AD7912/AD7922 is provided on this output as

a serial data stream. The bits are clocked out on the falling edge of the SCLK signal.

For the AD7922, the data stream consists of two leading zeros, the channel identifier bit that identifies

which channel the conversion result corresponds to, followed by the mode bit that indicates the

current mode of operation, followed by the 12 bits of conversion data with MSB first.

For the AD7912, the data stream consists of two leading zeros, the channel identifier bit that identifies

which channel the conversion result corresponds to, followed by the mode bit that indicates the

current mode of operation, followed by the 10 bits of conversion data with MSB first and two trailing

zeros.

2

3

CS

Chip Select. Active low logic input. This input provides the dual function of initiating conversions on

the AD7912/AD7922 and framing the serial data transfer.

3

2

SCLK

Serial Clock. Logic input. SCLK provides the serial clock for accessing data from the part. This clock

input is also used as the clock source for the AD7912/AD7922’s conversion process.

4

1

DIN

Data In. Logic input. The channel to be converted is provided on this input and is clocked into an

internal register on the falling edge of SCLK.

6, 5

7, 8

Analog Inputs. These two single-ended analog input channels are multiplexed into the on-chip

track-and-hold amplifier. The analog input channel to be converted is selected by writing to the third

7

6

GND

Analog Ground. Ground reference point for all circuitry on the AD7912/AD7922. All analog input

signals should be referred to this GND voltage.

8

5