7

OPA130, 2130, 4130

®

APPLICATIONS INFORMATION

OPA130 series op amps are unity-gain stable and suitable

for a wide range of general-purpose applications. Power

supply pins should be bypassed with 10nF ceramic capaci-

tors or larger.

OPA130 op amps are free from unexpected output phase-

reversal common with FET op amps. Many FET-input op

amps exhibit phase-reversal of the output when the input

common-mode voltage range is exceeded. This can occur in

voltage-follower circuits, causing serious problems in

control loop applications. OPA130 series op amps are free

from this undesirable behavior. All circuitry is completely

independent in dual and quad versions, assuring normal

behavior when one amplifier in a package is overdriven or

short-circuited.

OPERATING VOLTAGE

OPA130 series op amps operate with power supplies from

±2.25V to ±18V with excellent performance. Although

specifications are production tested with

±15V supplies,

most behavior remains unchanged throughout the full

operating voltage range. Parameters which vary signifi-

cantly with operating voltage are shown in the typical

performance curves.

OFFSET VOLTAGE TRIM

Offset voltage of OPA130 series amplifiers is laser trimmed

and usually requires no user adjustment. The OPA130

(single op amp version) provides offset voltage trim con-

nections on pins 1 and 5. Offset voltage can be adjusted by

connecting a potentiometer as shown in Figure 1. This

adjustment should be used only to null the offset of the op

amp, not to adjust system offset or offset produced by the

signal source. Nulling offset that is not produced by the

amplifier will change the offset voltage drift behavior of

the op amp.

V+

V–

100k

Ω

OPA130 single op amp only.

Use offset adjust pins only to null

offset voltage of op amp—see text.

Trim Range: ±5mV typ

OPA130

6

7

5

4

3

2

1

10nF

10nF

FIGURE 1. OPA130 Offset Voltage Trim Circuit.

INPUT BIAS CURRENT

The input bias current is approximately 5pA at room tem-

perature and increases with temperature as shown in the

typical performance curve “Input Bias Current vs Tempera-

ture.”

Input stage cascode circuitry assures that the input bias

current remains virtually unchanged throughout the full

input common-mode range of the OPA130. See the typical

performance curve “Input Bias Current vs Common-Mode

Voltage.”