am452 AME, Inc., am452 Datasheet - Page 17

• Manufacturer Part Number: am452
• Description: Voltage-to-current Transducer Ic With A Differential Input - Analog Microelectronics
• Manufacturer: AME, Inc.

Typical 2-wire application with a differential input signal
2) Example 2: V
In order to determine the system resistors R
For a measuring bridge with a signal of V
the external components in the AM452 circuitry should be dimensioned in such a way that the
output current range is 4...20mA. AM452 is configured in such a way that the entire current,
including the chip's quiescent current, flows through R
As in Example 1, R
example a value of 10k has been chosen for R
value of R
are as follows:
Figure 7: Typical 2-wire application for differential input signals
Analog Microelectronics GmbH
An der Fahrt 13, D – 55124 Mainz
AM452 – Voltage-to-current transducer IC
R
SET
0
2
3
4
has been set to 33k . Applying Equations (12) and (13) the values for R
V
AM452
BG
ZERO Stage
IN
OP2
IA
13
= 0...100mV differential, I
2
and R
. 0
. 0
with a differential input
02
004
1
Voltage Reference
A
A
4
12
5
C
can be freely selected within the boundary conditions. In this
R
0 (
1
OP1
2
2
1 .
R
15
1
V
33
5
System ground: Ground
R
8
5
7
IC ground: GND
3
16
33
1 (
(
R
R
IN
0
3
G
G
10
5
4
to R
SET
VI
= 0...100mV (without an offset) at the IA input
k
R
k
5
V/I Converter
OUT
1
SET Stage
k
5
2,
)
}
must first be determined.
with 5k selected for R
)
= 4...20mA (2-wire)
different
potentials!
0
(example for the 2-wire application).
2
14
GND
33
5
11
10
9
Phone: [phone]
Fax:
Internet:
Email: [e-mail]
8
February 2008 - Rev 1.2 - Page 17/21
R
5
(
T
R
1
D
R
connection
Ground
3
+49 (0)6131/91 073-30
5
0
1
2-wire
http://www.analogmicro.de
I
k
C
R
OUT
5
L
2
V
k
S
4
)
. V
REF
= 5V. The
1
and R
3