iC-NQC
preliminar y
Rev B1, Page 26/29
13-bit Sin/D CONVERTER WITH SIGNAL CALIBRATION
APPLICATION NOTES
Principle input circuits
PSIN
+
-
11µApp
+
PSIN
RS1
25kS
NSIN
RS2
25kS
NSIN
+
INPUT SIN
VREF
RS
120S
NSIN
NSIN
+
INPUT SIN
VREF
-
PSIN
-
1Vss to 120S
PSIN
-
SENSOR
case
iC-NQC
SENSOR
case
iC-NQC
Figure 20: Input circuit for current signals of 11 µA
with no ground reference. Offset calibra-
tion is not possible with this circuit.
Figure 19: Input circuit for voltage signals of 1 Vpp
with no ground reference. When ground
is not separated the connection NSIN to
VREF must be omitted.
R3
1k
S
R1
1k
S
-
R2
1k
S
+
-
R4
1k
S
PSIN
+
+5V
R001
1kS
R002
1kS
-
PSIN
+
V-GEN
1Vpp
-
NSIN
+
INPUT SIN
VREF
V-GEN
2Vpp
NSIN
-
+
INPUT SIN
VREF
iC-NQC
Figure 21: Input circuit for non-symmetrical voltage
or current source signals with ground ref-
erence (adaptation via resistors R3, R4).
R1
10k
S
iC-NQC
Figure 22: Simplified input wiring for non-
symmetrical voltage signals with ground
reference.
+TTL
-TTL or open
5kS
5kS
RS3
1kS
PSIN
+
-
PSIN
+
-
+SIN
+
-
R2
10k
S
120S
-SIN
RS1
5kS
RS2
5kS
CS1
220pF
-
RS4
1kS
NSIN
+
GAIN= 10
Ip
10µApp
In
10µApp
NSIN
-
INPUT SIN
+
INPUT SIN
VREF
ENCODER
VREF
case
CS2
47nF
iC-NQC
iC-NQC
Figure 23: Input circuit for complementary low-side
current source outputs, such as for op-
toencoder iC-WG.
Figure 24: Combined input circuit for 11 µA, 1 Vpp
(with 120
Ω
termination) or TTL encoder
signals. RS3/4 and CS1 serve as protec-
tion against ESD and transients.
ICHAUS [ IC-HAUS GMBH ]
