Datasheet

LTC1665/LTC1660
13
166560fa
TYPICAL APPLICATIONS
A Low Power Quad Trim Circuit with Coarse/Fine Adjustment
V
OUT4
V
OUT1
V
OUT3
V
OUT2
R1
COARSE
R1
COARSE
0.1μF
0.1μF
R1
4
1
2
3
11
3.3V 3.3V
R1
COARSE
R1 R2
R2
R2
FINE
R2
FINE
R2
FINE
R1
COARSE
R2
FINE
166560 TA01
2
15
1
GND
V
OUT A
V
OUT B
V
OUT C
V
OUT D
REF
CS/LD
SCK
3-WIRE
SERIAL
INTERFACE
V
CC
V
OUT H
V
OUT G
V
OUT F
V
OUT E
CLR
TO OTHER
LTC1665s
D
OUT
D
IN
16
DAC A DAC H
3 14
DAC B DAC G
4 13
DAC C DAC F
5
7
6
8
11
9
12
DAC D DAC E
ADDRESS
DECODER
CONTROL
LOGIC
SHIFT REGISTER
0.1μF
0.1μF
3.3V
1
4
2
U1
LTC1665
–
+
U2A
LT
®
1491
7
6
5
–
+
U2B
LT1491
LTC1258-2.5
0.1μF
0.1μF
R1
14
13
12
R2
–
+
U2D
LT1491
0.1μF
R1
8
9
10
R2
–
+
U2C
LT1491
R2 >> R1
V
OUT 1
= V
OUT A
+
Example: For R1 = 110Ω and R2 = 11k,
V
OUT 1
= V
OUT A
+ 0.01 V
OUT B
 
R1
R2
V
OUT B
Similarly V
OUT 2
, V
OUT 3
, V
OUT 4
10