Datasheet

ADS1281

SBAS378D –AUGUST 2007–REVISED JUNE 2010

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CONFIGURATION GUIDE

3. Verify register data. The register may be read

The ADS1281 offers two modes of operation: Pin

back for verification of device communications.

Control mode and Register Control mode. In Pin

4. Set the data mode. After register configuration,

Control mode, the operation of the device is

the device may be configured for Read Data

controlled by the pins; there are no registers to

Continuous mode, either by the Read Data

program. In Register Control mode, the registers are

Continuous command or configured in Read Data

used to control device operation. After RESET or

By Register mode using STOPC command.

power-on, the registers can be configured using the

following procedure: 5. Synchronize readings. Whenever SYNC is high,

the ADS1281 freely runs the data conversions.

1. Reset the SPI interface. Before using the SPI

To stop and restart the conversions, take SYNC

interface, it may be necessary to recover the SPI

low and then high.

interface (undefined I/O power-up sequencing

may cause false SCLK detection). To reset the 6. Read data. If the Read Data Continuous mode is

SPI interface, toggle the RESET pin or, when in active, the data are read directly after DRDY falls

Read Data Continuous mode, hold SCLK low for by applying SCLK pulses. If the Read Data

64 DRDY periods. Continuous mode is inactive, the data can only

be read by Read Data By Command. The Read

2. Configure the registers. The registers are

Data command must be sent in this mode to read

configured by either writing to them individually or

each conversion result (note that DRDY only

as a group. Software may be configured in either

asserts after each read data command is sent).

mode. The STOPC command must be sent

before register read/write operations to cancel the

Read Data Continuous mode.

Product Folder Link(s): ADS1281