Datasheet

LTC2754
14
2754f
OPERATION
Table 1. Command Codes
CODE
COMMAND
READBACK POINTER–
CURRENT INPUT WORD W
0
READBACK POINTER–
NEXT INPUT WORD W
+1
C3 C2 C1 C0
0010 Write Span DAC n Set by Previous Command Input Span Register DAC n
0011 Write Code DAC n Set by Previous Command Input Code Register DAC n
0100 Update DAC n Set by Previous Command DAC Span Register DAC n
0101 Update All DACs Set by Previous Command DAC Code Register DAC A
0110 Write Span DAC n
Update DAC n
Set by Previous Command DAC Span Register DAC n
0111 Write Code DAC n
Update DAC n
Set by Previous Command DAC Code Register DAC n
1000 Write Span DAC n
Update All DACs
Set by Previous Command DAC Span Register DAC n
1001 Write Code DAC n
Update All DACs
Set by Previous Command DAC Code Register DAC n
1010 Read Input Span Register DAC n Input Span Register DAC n
1011 Read Input Code Register DAC n Input Code Register DAC n
1100 Read DAC Span Register DAC n DAC Span Register DAC n
1101 Read DAC Code Register DAC n DAC Code Register DAC n
1111 No Operation Set by Previous Command DAC Code Register DAC n
– System Clear – DAC Span Register DAC A
– Initial Power-Up or Power Interupt – DAC Span Register DAC A
Codes not shown are reserved–do not use
Table 2. Address Codes
A3 A2 A1 A0 n
000
×
DAC A
001
×
DAC B
010
×
DAC C
011
×
DAC D
111
×
All DACs (Note 1)
Codes not shown are reserved–do not use.
× = Don’t Care.
Note 1. If readback is taken using the All DACs address, the LTC2754
defaults to DAC A.
Table 3. Span Codes
S3 S2 S1 S0 SPAN
×
0 0 0 Unipolar 0V to 5V
×
0 0 1 Unipolar 0V to 10V
×
0 1 0 Bipolar –5V to 5V
×
0 1 1 Bipolar –10V to 10V
×
1 0 0 Bipolar –2.5V to 2.5V
×
1 0 1 Bipolar –2.5V to 7.5V
Codes not shown are reserved–do not use.
× = Don’t Care.