Datasheet

TLE202x, TLE202xA, TLE202xB, TLE202xY
EXCALIBUR HIGH-SPEED LOW-POWER PRECISION
OPERATIONAL AMPLIFIERS

SLOS191D − FEBRUARY 1997 − REVISED NOVEMBER 2010
53
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
voltage-follower applications
The TLE202x circuitry includes input-protection diodes to limit the voltage across the input transistors; however,
no provision is made in the circuit to limit the current if these diodes are forward biased. This condition can occur
when the device is operated in the voltage-follower configuration and driven with a fast, large-signal pulse. It
is recommended that a feedback resistor be used to limit the current to a maximum of 1 mA to prevent
degradation of the device. This feedback resistor forms a pole with the input capacitance of the device. For
feedback resistor values greater than 10 kΩ, this pole degrades the amplifier phase margin. This problem can
be alleviated by adding a capacitor (20 pF to 50 pF) in parallel with the feedback resistor (see Figure 71).
C
F
= 20 pF to 50 pF
I
F
≤ 1 mA
R
F
V
CC +
V
CC −
V
O
V
I
−
+
Figure 71. Voltage Follower
Input offset voltage nulling
The TLE202x series offers external null pins that further reduce the input offset voltage. The circuit in
Figure 72 can be connected as shown if this feature is desired. When external nulling is not needed, the null
pins may be left disconnected.
1 kΩ GND (single supply)
V
CC
− (split supply)
5 kΩ
OFFSET N2
−
+
OFFSET N1
IN −
IN +
Figure 72. Input Offset Voltage Null Circuit