Datasheet

9
LTC1605-1/LTC1605-2
APPLICATIONS INFORMATION
WUU
U
INPUT VOLTAGE (V)
–FS/2 0V
OUTPUT CODE
1605-1/2 F06b
011...111
011...110
000...001
000...000
111...111
111...110
100...000
100...001
–1
LSB
1
LSB
BIPOLAR
ZERO
FS/2 – 1LSB
FS = 8V
1LSB = FS/65536
Figure 6B. LTC1605-2 Bipolar Transfer Characteristics
CODE
0
500
1500
1000
2500
2000
4000
3500
3000
4500
COUNT
1605-1/2 F07
–5–4–3–2–1012345
Figure 7. Histogram for 10000 Conversions
INPUT VOLTAGE (V)
0V
OUTPUT CODE
1605-1/2 F06a
111...111
111...110
000...000
000...001
1
LSB
UNIPOLAR
ZERO
FS – 1LSB
FS = 4V
1LSB = FS/65536
Figure 6a. LTC1605-1 Unipolar Transfer Characteristics
Figure 5. 0V to 4V Input for the LTC1605-1 and
±4V for the LTC1605-2 with Offset and Gain Trim
+
5
4
3
2
1
2.2µF
+
2.2µF
33.2k
1%
0V TO 4V
OR ±4V
INPUT 200Ω
1%
V
IN
AGND1
REF
CAP
AGND2
LTC1605-1
LTC1605-2
1605-1/2 F05
576k
R4
50k
R3
50k
OFFSET
TRIM
GAIN
TRIM
5V
S
S
–
+
1605-1/2 F03
INTERNAL
CAPACITOR
DAC
BANDGAP
REFERENCE
V
ANA
4k
2.2µF
CAP
(2.5V)
2.2µF
REF
(2.5V)
4
3
Figure 3. Internal or External Reference Source
+
5
4
3
2
1
2.2µF
+
2.2µF
33.2k
1%
0V TO 4V
OR ±4V
INPUT
200Ω
1%
V
IN
AGND1
REF
CAP
AGND2
LTC1605-1
LTC1605-2
1605-1/2 F04
Figure 4. 0V to 4V Input for the LTC1605-1
and ±4V for the LTC1605-2 Without Trim