DAC1220
www.ti.com...................................................................................................................................... SBAS082G –FEBRUARY 1998–REVISED SEPTEMBER 2009
Table 13. Command Register Bits (continued)
BIT(S)
NAME
VALUE
DESCRIPTION
2
MSB
Selects the order in which bits are shifted in and out of the DAC1220, except
when writing to the command register. The command register is always written
to MSB first. Reads from the command register are according to this bit.
0
1
Data is shifted MSB first (default).
Data is shifted LSB first.
Operating mode.
1-0
MD
00b
01b
Normal mode (default).
Self calibration mode. (No other bits should be changed in the Command
Register when setting this mode.)
10b
11b
Sleep mode.
Reserved.
Data Input Register (DIR)
The Data Input Register determines the output
voltage in Normal mode.
After reset, the OCR contains zero. See the
Calibration section for further details about the OCR.
In Sleep mode, writing to this register has no effect
on the output, but the value is stored. The value in
the DIR becomes effective immediately upon entering
Normal mode.
Full-Scale Calibration Register (FCR)
The Full-Scale Calibration Register stores the gain
calibration constant. The content of the DIR is
adjusted multiplicatively by this value before
conversion by the DAC.
After reset, the DIR contains zero.
See the section, Setting the Output Voltage for further
details about the Data Input Register.
In Sleep mode, writing to this register has no effect
on the output, but the value is stored. The value in
the FCR becomes effective immediately upon
entering Normal mode.
Offset Calibration Register (OCR)
The Offset Calibration Register contains a 24-bit
two's complement value. This value is added to the
value in the DIR before conversion by the DAC.
After reset, the FCR contains 800000h.
See the Calibration section for further details about
the FCR.
In Sleep mode, writing to this register has no effect
on the output, but the value is stored. The value in
the OCR becomes effective immediately upon
entering Normal mode.
Copyright © 1998–2009, Texas Instruments Incorporated
Submit Documentation Feedback
17
Product Folder Link(s): DAC1220
TI [ TEXAS INSTRUMENTS ]
