Typical application schematics
LM2903
Figure 14. Low frequency op- amp with offset Figure 15. Zero crossing detector
adjust
(single power supply)
5V
5V
Offset
adjust
100 kΩ
5V
R
2
R
S
R
1
100 kΩ
1 MΩ
1 MΩ
100 kΩ
5.1 kΩ
5.1 kΩ
15 kΩ
1/ 2
LM2903
5.1 kΩ
1/ 2
LM2903
e
l
2N 2222
e
l
~
0.5
μ
F
R1
100 kΩ
1 kΩ
e
o
1N4148
20 MΩ
10 kΩ
Figure 16. Limit comparator
V
CC
(12 V)
Figure 17. Split-supply applications - zero
crossing detector
15 V
2R
S
V
(ref)
high
R
S
10 kΩ
1/ 2
LM2903
5.1 kΩ
Lamp
1/2
LM2903
e
o
e
I
~
1/2
LM2903
e
I
~
2R
S
V
(ref)
low
2N 2222
15 V
Figure 18. Crystal controlled oscillator
V
CC
= 15 V
Figure 19. Comparator with a negative
reference
15 V
200 kΩ
100 kΩ
V
CC
0.1
μF
1/2
LM2903
2 kΩ
5.1 kΩ
1/2
LM2903
0
e
o
e
o
e
I
~
f = 100 kHz
200 kΩ
5V
15 V
8/18
Doc ID 2470 Rev 10
STMICROELECTRONICS [ STMICROELECTRONICS ]
