Preliminary Technical Data

AD5763

Rev. PrA | Page 11 of 31

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

AD5763

TOP VIEW

(Not to Scale)

SYNC

SCLK

SDIN

SDO

CLR

LDAC

D1

D0

NC

NC

VOUTA

AGNDA

AGNDB

VOUTB

NC

NC

1

32

25

916

8

24

17

PIN 1

INDICATOR

Figure 6. Pin Configuration

Table 6. Pin Function Descriptions

Pin No.

Mnemonic

Description

1

SYNC

Active Low Input. This is the frame synchronization signal for the serial interface. While SYNC is low,

data is transferred in on the falling edge of SCLK.

2

SCLK

Serial Clock Input. Data is clocked into the shift register on the falling edge of SCLK. This operates at

clock speeds up to 30 MHz.

3

SDIN

Serial Data Input. Data must be valid on the falling edge of SCLK.

4

SDO

Serial Data Output. Used to clock data from the serial register in daisy-chain or readback mode.

Negative Edge Triggered Input. Asserting this pin sets the DAC registers to 0x0000.

6

LDAC

Load DAC. Logic input. This is used to update the DAC registers and consequently the analog outputs.

When tied permanently low, the addressed DAC register is updated on the rising edge of SYNC. If

LDAC is held high during the write cycle, the DAC input register is updated but the output update is

held off until the falling edge of LDAC. In this mode, all analog outputs can be updated

simultaneously on the falling edge of LDAC. The LDAC pin must not be left unconnected.

7, 8

D0, D1

D0 and D1 form a digital I/O port. The user can set up these pins as inputs or outputs that are

configurable and readable over the serial interface. When configured as inputs, these pins have weak

9

RSTOUT

Reset Logic Output. This is the output from the on-chip voltage monitor used in the reset circuit. If

desired, it can be used to control other system components.

10

RSTIN

Reset Logic Input. This input allows external access to the internal reset logic. Applying a Logic 0 to

this input clamps the DAC outputs to 0 V. In normal operation, RSTIN should be tied to Logic 1.

Register values remain unchanged.

11

DGND

Digital Ground Pin.

12

Digital Supply Pin. Voltage ranges from 2.7 V to 5.25 V.

13, 31

Positive Analog Supply Pins. Voltage ranges from 4.75 V to 5.25 V.

14

PGND

Ground Reference Point for Analog Circuitry.

15, 30

Negative Analog Supply Pins. Voltage ranges from –4.75 V to –5.25 V.

16

ISCC

This pin is used in association with an optional external resistor to AGND to program the short-circuit

current of the output amplifiers. Refer to the AD5763 Features section on page 25 for further details.

17

NC

No Internal Connection

18

NC

No Internal Connection

19

VOUTB

Analog Output Voltage of DAC B. Buffered output with a nominal full-scale output range of ±4.096 V. The

output amplifier is capable of directly driving a 5 kΩ, 200 pF load.

20

AGNDB

Ground Reference Pin for DAC B Output Amplifier.

21

AGNDA

Ground Reference Pin for DAC A Output Amplifier.