AD7788ARMZ datasheet(15/20 Pages) AD

15 / 20 page

AD7788/AD7789

Rev. B | Page 15 of 20

The serial interface can be reset by writing a series of 1s on the

DIN input. If a Logic 1 is written to the AD7788/AD7789 for

at least 32 serial clock cycles, the serial interface is reset. This

ensures that the interface can be reset to a known state if the

interface gets lost due to a software error or a glitch in the

system. Reset returns the interface to the state in which it is

expecting a write to the communications register. This oper-

ation resets the contents of all registers to their power-on values.

The AD7788/AD7789 can be configured to continuously

convert or to perform a single conversion. See Figure 11

through Figure 13.

Single Conversion Mode

In single-conversion mode, the AD7788/AD7789 are placed in

power-down mode between conversions. When a single conver-

sion is initiated by setting MD1 to 1 and MD0 to 0 in the mode

version, and then return to power-down mode. The devices

require 1 ms to power up and settle. The AD7788/AD7789

then perform a conversion, requiring a time period of

2 × tADC. DOUT/RDY goes low to indicate the completion of a

conversion.

When the data-word has been read from the data register,

DOUT/RDY goes high. If CS is low, DOUT/RDY remains high

until another conversion is initiated and completed. The data

DOUT/ RDY has gone high.

Continuous Conversion Mode

This is the default power-up mode. The AD7788/AD7789

continuously convert, the RDY pin in the status register going

low each time a conversion is complete. If CS is low, the

DOUT/RDY line also goes low when a conversion is complete.

To read a conversion, the user can write to the communications

pin as soon as SCLK pulses are applied to the ADC. DOUT/

RDY returns high when the conversion is read. The user can

read this register additional times, if required. However, the

user must ensure that the data register is not being accessed

at the completion of the next conversion or else the new

conversion word is lost.

DIN

0x10

0x82

DATA

SCLK

DOUT/RDY

0x38

Figure 11. Single Conversion

DIN

SCLK

DOUT/RDY

0x38

DATA

Figure 12. Continuous-Conversion Mode

AD7788ARMZ Datasheet(PDF) 15 Page - Analog Devices

AD7788ARMZ Datasheet(HTML) 15 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Datasheet Download

Link URL