ISL28134IBZ Datasheet, PDF (15/25 Pages) Intersil Corporation – 5V Ultra Low Noise, Zero Drift Rail-to-Rail Precision Op Amp

R_I
V_IN
R_S
R_G
R_F
+2.5V
-
+
-2.5V
ISL28134
V_OUT
R_L
R_S//R_G = R_S//R_G
FIGURE 43. CIRCUIT IMPLEMENTATION FOR REDUCING INPUT
BIAS CURRENTS
IN+ and IN- Protection
The ISL28134 is capable of driving the input terminals up to and
beyond the supply rails by about 0.5V. Back biased ESD diodes
from the input pins to the V+ and V- rails will conduct current
when the input signals go more than 0.5V beyond the rail (see
Figure 44). The ESD protection diodes must be current limited to
20mA or less to prevent damage of the IC. This current can be
reduced by placing a resistor in series with the IN+ and IN- inputs
in the event the input signals go beyond the rail.
IN-
-
R_IN
IN+
V_IN
+
ESD
DIODES
V+
V-
V_OUT
R_L
FIGURE 44. INPUT CURRENT LIMITING
15
FN6957.3
December 22, 2011