Datasheet

TLC27L4, TLC27L4A, TLC27L4B, TLC27L4Y, TLC27L9
LinCMOS PRECISION QUAD OPERATIONAL AMPLIFIERS
SLOS053C – OCTOBER 1987 – REVISED AUGUST 1994
32
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
noise performance (continued)
V
I
(a) NONINVERTING AMPLIFIER (c) UNITY-GAIN AMPLIFIER
–
+
(b) INVERTING AMPLIFIER
V
I
–
+
–
+
V
I
V
O
V
O
V
O
Figure 40. Guard-Ring Schemes
output characteristics
The output stage of the TLC27L4 and TLC27L9 is designed to sink and source relatively high amounts of current
(see typical characteristics). If the output is subjected to a short-circuit condition, this high current capability can
cause device damage under certain conditions. Output current capability increases with supply voltage.
All operating characteristics of the TLC27L4 and TLC27L9 were measured using a 20-pF load. The devices
drive higher capacitive loads; however, as output load capacitance increases, the resulting response pole
occurs at lower frequencies, thereby causing ringing, peaking, or even oscillation (see Figure 41). In many
cases, adding a small amount of resistance in series with the load capacitance alleviates the problem.
–
+
2.5 V
V
O
C
L
–2.5 V
V
I
(a) C
L
= 20 pF, R
L
= NO LOAD
(b) C
L
= 260 pF, R
L
= NO LOAD
(c) C
L
= 310 pF, R
L
= NO LOAD (d) TEST CIRCUIT
T
A
= 25°C
f = 1 kHz
V
IPP
= 1 V
Figure 41. Effect of Capacitive Loads and Test Circuit