LTC1655I Linear Technology, LTC1655I Datasheet - Page 7

• Manufacturer Part Number: LTC1655I
• Description: 16-Bit Rail-to-Rail Micropower DAC in SO-8 Package
• Manufacturer: Linear Technology

APPLICATIONS
Rail-to-Rail Output Considerations
In any rail-to-rail DAC, the output swing is limited to
voltages within the supply range.
If the DAC offset is negative, the output for the lowest
codes limits at 0V as shown in Figure 1b.
Similarly, limiting can occur near full scale when the REF
pin is tied to V
NEGATIVE
OFFSET
VOLTAGE
OUTPUT
Figure 1. Effects of Rail-to-Rail Operation On a DAC Transfer Curve. (a) Overall Transfer Function (b) Effect of Negative
Offset for Codes Near Zero Scale (c) Effect of Positive Full-Scale Error for Input Codes Near Full Scale When V
0V
CC
/2. If V
U
REF
INPUT CODE
INFORMATION
U
(b)
= V
CC
/2 and the DAC full-scale
VOLTAGE
W
OUTPUT
V
CC
0
V
U
REF
= V
CC
INPUT CODE
/2
32768
(a)
error (FSE) is positive, the output for the highest codes
limits at V
can occur if V
Offset and linearity are defined and tested over the region
of the DAC transfer function where no output limiting can
occur.
65535
CC
as shown in Figure 1c. No full-scale limiting
REF
is less than (V
INPUT CODE
(c)
CC
V
REF
– FSE)/2.
= V
CC
/2
LTC1655
REF
= V
V
OUTPUT
VOLTAGE
CC
CC
1655 F01
POSITIVE
FSE
/2
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