LTC2751
12
2751fa
Output Ranges
The LTC2751 is a current-output, parallel-input precision
multiplying DAC with software-programmable output
ranges. SoftSpan provides two unipolar output ranges
(0V to 5V and 0V to 10V), and four bipolar ranges (±2.5V,
±5V, ±10V and –2.5V to 7.5V). These ranges are obtained
when an external precision 5V reference is used. When
a reference voltage of 2V is used, the SoftSpan ranges
become: 0V to 2V, 0V to 4V, ±1V, ±2V, ±4V and –1V to
3V. The output ranges are linearly scaled for references
other than 2V and 5V.
TiMing DiagraMs
operaTion
Digital Section
The LTC2751 family has four internal interface registers
(see Block Diagram). Tw o of these—one input and one
DAC register—are dedicated to the data I/O port, and two
to the span I/O port. Each port is thus double-buffered.
The double-buffered feature provides the capability to
simultaneously update the span and code, which allows
smooth voltage transitions when changing output ranges.
It also permits the simultaneous updating of multiple DACs.
CLR
WR
2751 TD01
3
t
6
t
5
t
7
t
8
t
4
t
2
t
1
I/O
INPUT
UPD
D/S
t
25
WR
2751 TD02
I/O
OUTPUT
I/O
INPUT
READ
UPD
D/S
t
13
t
23
t
15
t
19
t
17
t
20
t
22
t
18
t
14
t
24
Write, Update and Clear Timing
Readback Timing
