Data Sheet

AD7983

Rev. B | Page 7 of 24

PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS

REF

1

VDD

2

IN+

3

IN–

4

VIO

10

SDI

9

SCK

8

SDO

7

GND

5

CNV

6

AD7983

TOP VIEW

(Not to Scale)

Figure 4. 10-Lead MSOP Pin Configuration

REF 1

VDD 2

IN+ 3

IN– 4

10 VIO

9 SDI

8 SCK

7 SDO

GND 5

6 CNV

AD7983

TOP VIEW

(Not to Scale)

NOTES

1. EXPOSED PAD. CONNECT THE EXPOSED PAD

TO GND. THIS CONNECTION IS NOT REQUIRED

TO MEET THE ELECTRICAL PERFORMANCES.

Figure 5. 10-Lead LFCSP Pin Configuration

Table 6. Pin Function Descriptions

Pin No.

Mnemonic

Description

1

REF

AI

Reference Input Voltage. The REF range is from 2.9 V to 5.1 V. It is referred to the GND pin. This pin should

be decoupled closely to the pin with a 10 µF capacitor.

2

VDD

P

Power Supply.

3

IN+

AI

Analog Input. It is referred to IN−. The voltage range, for example, the difference between IN+ and IN−, is

4

IN−

AI

Analog Input Ground Sense. To be connected to the analog ground plane or to a remote sense ground.

5

GND

P

Power Supply Ground.

6

CNV

DI

Convert Input. This input has multiple functions. On its risng edge, it initiates the conversions and

selects the interface mode of the part: chain or CS mode. In CS mode, it enables the SDO pin when low.

In chain mode, the data should be read when CNV is high.

7

SDO

DO

Serial Data Output. The conversion result is output on this pin. It is synchronized to SCK.

8

SCK

DI

Serial Data Clock Input. When the part is selected, the conversion result is shifted out by this clock.

9

SDI

DI

Serial Data Input. This input provides multiple features. It selects the interface mode of the ADC as

follows:

Chain mode is selected if SDI is low during the CNV rising edge. In this mode, SDI is used as a data

input to daisy-chain the conversion results of two or more ADCs onto a single SDO line. The digital

data level on SDI is output on SDO with a delay of 16 SCK cycles.

CS mode is selected if SDI is high during the CNV rising edge. In this mode, either SDI or CNV can

enable the serial output signals when low; if SDI or CNV is low when the conversion is complete,

the busy indicator feature is enabled.

10

VIO

P

Input/Output Interface Digital Power. Nominally at the same supply as the host interface (1.8 V, 2.5 V,

3 V, or 5 V).

EPAD

Exposed Pad. For the 10-lead LFCSP only, connect the exposed pad to GND. This connection is not

required to meet the electrical performances.

1

AI = analog input, DI = digital input, DO = digital output, and P = power.