LTC1661 Linear Technology, LTC1661 Datasheet - Page 8

• Manufacturer Part Number: LTC1661
• Description: Micropower Dual 10-Bit DAC in MSOP
• Manufacturer: Linear Technology

OPERATIO
LTC1661
Table 2. DAC Control Functions
8
CS/LD
A3 A2 A1 A0
SCK
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
D
IN
CONTROL
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
U
INPUT REGISTER
Load DACs A, B
Load DAC A
Load DAC B
Load DAC A
Load DAC B
(SCK ENABLED)
10-Bit Code
No Change
No Change
No Change
No Change
with Same
STATUS
A3
1
CONTROL CODE
A2
2
A1
3
Update Outputs
Update Outputs
DAC REGISTER
Update Outputs
Update Outputs
No Update
No Update
No Update
No Update
No Update
STATUS
A0
4
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Figure 1. Register Loading Sequence
D9
5
D8
6
POWER-DOWN STATUS
D7
7
(SLEEP/WAKE)
INPUT WORD W
No Change
No Change
No Change
D6
Wake
Wake
Wake
Wake
Sleep
Wake
8
INPUT CODE
D5
9
0
D4
10
D3
COMMENTS
No Operation. Power-Down Status Unchanged
(Part Stays In Wake or Sleep Mode)
Load Input Register A with Data. DAC Outputs
Unchanged. Power-Down Status Unchanged
Load Input Register B with Data. DAC Outputs
Unchanged. Power-Down Status Unchanged
Load Both DAC Regs with Existing Contents of Input
Regs. Outputs Update. Part Wakes Up
Load Input Reg A. Load DAC Regs with New Contents
of Input Reg A and Existing Contents of Reg B. Outputs
Update. Part Wakes Up
Load Input Reg B. Load DAC Regs with Existing Contents
of Input Reg A and New Contents of Reg B. Outputs
Update. Part Wakes Up
Part Wakes Up. Input and DAC Regs Unchanged. DAC
Outputs Reflect Existing Contents of DAC Regs
Part Goes to Sleep. Input and DAC Regs Unchanged. DAC
Outputs Set to High Impedance State
Load Both Input Regs. Load Both DAC Regs with New
Contents of Input Regs. Outputs Update. Part Wakes Up
11
D2
12
D1
13
D0
14
DON’T CARE
X1
15
X0
16
(LTC1661
RESPONDS)
1661 F01