Datasheet

Industrial Converter and Protector IC AM460
analog microelectronics
April 2003
13/18
Example 3:
To obtain a signal of V
INP
= 0...1V at the OP1 input the external components are to be dimensioned in such a
way that the output current has a range of 0...20mA (i.e. I
SET
= 0 ⇒ SET = GND) and the output voltage one of
0...10V.
Using Equation 14 the output voltage is defined as follows:
2.21
2
1
⋅








+⋅=
R
R
VV
INPOUT
⇒
55.31
V12.2
V10
1
2.2
2
1
≈−
⋅
=−
⋅
=
INP
OUT
V
V
R
R
i.e.
55.41
2
1
=+=
R
R
G
GAIN
The following then applies to the output current:
00
88
R
G
VI
R
G
VI
GAIN
INPSET
I
INPOUT
⋅=+⋅=
⇒
Ω≈
⋅
=⋅= 44.28
mA208
55.4
V1
8
0
OUT
GAIN
INP
I
G
VR
Observing the boundary conditions, the following values are obtained for the external components:
R
0
≈ 28.44Ω R
1
≈ 35.5kΩ R
2
= 10kΩ
R
5
= 39Ω R
L
= 0...600Ω C
1
= 2.2µF
Ground
R
5
R
L
1
Single-ended
input voltage
Connections setting unused function blocks to a defined operating point
I
SET
= 0
V
BG
1
2
AM460
OP3
OP2
R
1
R
2
4
OP1
5
3
C
1
Voltage Reference
R
0
7146
13
15
16
12
11
8
9
10
V
I
T
1
D
1
3-wire connection
V
INP
V
S
V
OUT
I
OUT
Figure 7: Typical application for input signals referenced to ground