LMC7101_05 Datasheet, PDF (10/12 Pages) Micrel Semiconductor – Low-Power Operational Amplifier

LMC7101
Typical Circuits
Some single-supply, rail-to-rail applications for which the
LMC7101 is well suited are shown in the circuit diagrams of
Figures 3 through 7.
V+
V_IN
3
0V to ^{V +}
A_V ⁴
2 _LMC7101
1
5
V_OUT
0V to V+
R2
R1 ^900k
100k
Figure 3a. Noninverting Amplifier
1V0+0
A_V
=
1+
R2
R1
≈
10
0
0
V_IN (V)
100
Figure 3b. Noninverting Amplifier Behavior
V+
V_IN
3
0V to V+
4
2 _LMC7101
1
5
V_OUT
0V to V+
V_OUT = V_IN
Figure 4. Voltage Follower
Micrel, Inc.
V_S
0.5V to Q1 V_CEO(sus)
V_OUT
V+
0V to V+
V_IN
3
0V to 2V
2 _LMC7101
I_OUT
1
4
5
{ ^Q1
2N3904
V_CEO = 40V
I_C(max) = 200mA
R_S
Change Q1 and R_S
for higher current
10Ω
1_⁄2W
and/or different gain.
I_OUT
=
V_IN
R_S
= 100mA/V
as
shown
Figure 5. Voltage-Controlled Current Sink
C1
0.001µF
R4
100k
V+
4
2 _LMC7101
1
3
5
V_OUT
V+
0V
R2
V+
100k
R4
R3 ^100k
100k
Figure 6. Square Wave Oscillator
C_{IN R1}
33k
R2
330k
V+
4
2 _LMC7101
1
C_OUT
V_OUT
3
5
0V
R_L
R3
V+
330k
R4
330k
C1
1µF
A_V
=
−
R2
R1
=
330k
33k
=
−10
Figure 7. AC-Coupled Inverting Amplifier
LMC7101
10
February 2005