Datasheet

LTC2758
14
2758fa
For more information www.linear.com/LTC2758
OPERATION
Examples
1. Load DAC A with 0V to 10V range, output at zero
volts; and DAC B with ±10V range, output at zero
volts. Note the DAC outputs should change at the
same time.
a) CS/LD↓. Clock SDI:
00101111 00000000 00000011 00000000
b) CS/LD↑
Span Input register- Range of DACs set to bipolar ±10V.
c) CS/LD↓. Clock SDI:
00100000 00000000 00000001 00000000
d) CS/LD↑
Span Input register- Range of DAC A set to unipolar
0V to 10V.
e) CS/LD↓. Clock SDI:
00111111 10000000 00000000 00XXXXXX
f) CS/LD↑
Code Input register- Code of all DACs set to mid-scale.
g) CS/LD↓. Clock SDI:
00110000 00000000 00000000 00XXXXXX
h) CS/LD↑
Code Input register- Code of DAC A set to zero.
i) CS/LD↓. Clock SDI:
01001111 XXXXXXXX XXXXXXXX XXXXXXXX
j) CS/LD↑
Update all DACs for both Code and Range.
k) Alternatively steps i and j could be replaced with
LDAC .
2. Load DAC B with ±2.5V range with its output at zero
volts. Use readback to check Input register contents
before updating the DAC output (i.e., before copying
Input register contents into DAC registers). Note that
after power-on, the code in Input registers is zero.
a) CS/LD↓. Clock SDI:
00110010 10000000 00000000 00XXXXXX
b) CS/LD↑
Code Input register- DAC B set to mid-scale.
c) CS/LD↓. Clock SDI:
00100010 00000000 00000100 00000000
Data out on SRO:
10000000 00000000 00000000
Verifies Code Input register- DAC B set to mid-scale.
d) CS/LD↑
Span Input register- Range of DAC B set to Bipolar
±2.5V range.
e) CS/LD↓. Clock SDI:
10100010 XXXXXXXX XXXXXXXX XXXXXXXX
Data Out on SRO:
00000000 00000100 00000000
Verifies Span Input register- DAC B set to Bipolar
±2.5V Range.
CS/LD↑
f) CS/LD↓. Clock SDI:
01000010 XXXXXXXX XXXXXXXX XXXXXXXX
g) CS/LD↑
Update DAC B for both Code and Range
h) Alternatively steps f and g could be replaced with
LDAC .