AD7766
Rev. C | Page 9 of 24
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
06
44
9-
00
6
1
2
3
4
5
6
7
8
VREF+
REFGND
VIN+
SYNC/PD
AGND
VIN–
AVDD
DVDD
16
15
14
13
12
11
10
9
SDI
MCLK
SCLK
SDO
VDRIVE
DGND
DRDY
CS
AD7766/
AD766-1/
AD7766-2
TOP VIEW
(Not to Scale)
Figure 6. 16-Lead TSSOP Pin Configuration
Table 5. Pin Function Descriptions
Pin No.
Mnemonic
Description
1
AVDD
+2.5 V Analog Power Supply.
2
VREF+
Reference Input for the AD7766/AD7766-1/AD7766-2. An external reference must be applied to this input pin. The
VREF+ input can range from 2.4 V to 5 V. The reference voltage input is independent of the voltage magnitude
applied to the AVDD pin.
3
REFGND
Reference Ground. Ground connection for the reference voltage. The input reference voltage (VREF+) should be
decoupled to this pin.
4
VIN+
Positive Input of the Differential Analog Input.
5
VIN
Negative Input of the Differential Analog Input.
6
AGND
Power Supply Ground for Analog Circuitry.
7
SYNC/PD
Synchronization and Power-Down Input Pin. This pin has dual functionality. It can be used to synchronize multiple
AD7766/AD7766-1/AD7766-2 devices and/or to put the AD7766/AD7766-1/AD7766-2 devices into power-down
8
DVDD
2.5 V Digital Power Supply Input. In cases where a logic voltage of 2.5 V for interfacing is used, (2.5 V applied to
VDRIVE pin), the DVDD and VDRIVE pins may be connected to the same voltage supply rail.
9
VDRIVE
Logic Power Supply Input, 1.8 V to 3.6 V. The voltage supplied at this pin determines the operating voltage of the
digital logic interface.
10
SDO
Serial Data Output. The conversion result from the AD7766/AD7766-1/AD7766-2 is output on the SDO pin as a 24-bit,
twos complement, MSB first, serial data stream.
11
DGND
Digital Logic Power Supply Ground.
12
DRDY
Data Ready Output. A falling edge on the DRDY signal indicates that a new conversion data result is available in the
output register of the AD7766/AD7766-1/AD7766-2. See the
section for
further details.
13
SCLK
Serial Clock Input. The SCLK input provides the serial clock for all serial data transfers with the AD7766/AD7766-1/
14
MCLK
Master Clock Input. The sampling frequency of the AD7766/AD7766-1/AD7766-2 is equal to the MCLK frequency.
15
SDI
Serial Data Input. This is the daisy-chain input of the AD7766/AD7766-1/AD7766-2. See the
Daisy Chaining section
for further details.
16
CS
Chip Select Input. The CS input selects a specific AD7766/AD7766-1/AD7766-2 device and acts as an enable on the
SDO pin. In cases where CS is used, the MSB of the conversion result is clocked onto the SDO line on the CS falling
edge. The CS input allows multiple AD7766/AD7766-1/AD7766-2 devices to share the same SDO line. This allows
the user to select the appropriate device by supplying it with a logic low CS signal, which enables the SDO pin of
the device concerned. See the
section for further details.