
IXR100
8
FIGURE 6. Elevation and Suppression Circuits.
4. The maximum input signal level (
V
IN
) is 1V with R
S
open and is less as R
S
decreases in value.
5. Always return the current references to COM (pin 5)
through an appropriate value of R
CM
to keep V
CM
within
its operating range. Also, operate the current sources
within their rated compliance voltage:
V
IN
+ ≤
V
IREF
≤
(Com + 7V)
6. Always choose R
L
, (including line resistance) so that the
voltage between pins 18 and 28 (+V
S
) remains within the
11.6V to 36V range as the output changes between 4mA
and 20mA.
7. It is recommended that a reverse polarity protection diode
be used. This will prevent damage to the IXR100 caused
by a transient or long-term reverse bias between pins 18
and 28. This diode can be connected in either of the two
positions shown in Figure 7, but each connection has its
trade-off. The series-connected diode will add to the
minimum voltage at which the IXR100 will operate but
offers loop and device protection against both reverse
connections and transients. The reverse-biased diode in
parallel with the IXR100 preserves 11.6V minimum
operation and offers device protection, but could allow
excessive current flow in the receiving instrument if the
field leads are accidently reversed. This is particularly
important if the receiving equipment has particularly low
resistance or uses higher voltage supplies. In general, the
series diode is recommended unless 12V operation is
necessary. In either case a 1N4148 diode is suitable.
8. Use a layout which minimizes parasitic inductance and
capacitance, especially in high gain.
RECOMMENDED HANDLING
PROCEDURES FOR INTEGRATED CIRCUITS
All semiconductor devices are vulnerable, in varying
degrees, to damage from the discharge of electrostatic
energy. Such damage can cause performance degradation or
failure, either immediate or latent. As a general practice, we
recommend the following handling procedures to reduce the
risk of electrostatic damage.
1. Remove static-generating materials, such as untreated
plastic, from all areas where microcircuits are handled.
2. Ground all operators, equipment, and work stations.
3. Transport and ship microcircuits, or products incorporat-
ing microcircuits, in static-free, shielded containers.
4. Connect together all leads of each device by means of a
conductive material, when the device is not connected
into a circuit.
–
V
IN
e'
2
+
0.4mA
0.4mA
–
+
R
4
V
4
0.8mA
R
T
–
e'
2
+
0.4mA
0.4 mA
–
+
R
4
V
4
0.8mA
R
T
–
+
–
+
–
e'
2
+
0.8mA
–
+
R
4
V
4
0.8mA
–
+
–
+
0.8mA
–
+
R
4
V
4
0.8mA
–
+
e'
2
V
IN
V
IN
V
IN
V
IN
= (e'
2
–V
4
)
V
4
= 0.8mA
X
R
4
(c) Elevated Zero Range
V
IN
= (e'
2
+V
4
)
V
4
= 0.8mA
X
R
4
(d) Suppressed Zero Range
V
IN
= (e'
–V
4
)
V
4
= 0.4mA
X
R
4
e'
2
= 0.4mA
X
R
T
(a) Elevated Zero Range
V
IN
= (e'
+V
4
)
V
4
= 0.4mA
X
R
4
e'
2
= 0.4mA
X
R
T
(b) Suppressed Zero Range