VOLTAGE/CURRENT CONVERTER
FEATURES
•
Wide Supply Voltage Range: 6...35V
•
Wide Operating Temperature Range:
–40°C...+85°C
•
Adjustable Voltage Reference:
4.5 to 10V
•
Operational Amplifier Input:
0.5...4.5V, 0...5V, other
•
Adjustable Offset Current
•
Available as Three– (0/4...20mA) or
Two–Wire Version (4...20mA)
•
Adjustable Output Current Range
•
Protection Against Reverse Polarity
•
Protected Current Output
AM422
GENERAL DESCRIPTION
The AM422 is a low cost monolithic voltage–
to–current converter specially designed for
analog signal transmission. The AM422 is
available in a 3– or 2–wire version, which al-
lows applications with flexible input voltage
ranges to be used for a standard output current.
Output current range and current offset level
are freely adjustable by external resistors. The
IC consists of three basic sections: an opera-
tional amplifier input stage for single ended
input signals (0.5–4.5V, 0–10V, or other), a
programmable 4.5 to 10V reference for trans-
ducer excitation, and a current output, freely
adjustable in a wide current range (4–20mA,
0–20mA, other). With the broad spectrum of
possible input signals the AM422 is a flexible
and multipurpose voltage–to–current converter
for single ended transducers or voltage trans-
mission.
APPLICATIONS
•
•
•
•
Sensor Interface
Industrial Process Control
Programmable Current Source
Current Source Reference
DELIVERY
•
DIL8 packages (samples)
•
SOP8 packages
•
Dice on 5“ blue foil
BLOCK DIAGRAM
VSET
6
SET
8
1
V
REF
2
G
=1
Reference Voltage
VCC
VREF
AM422
5
V
VIN
4
Input
Amplifier
2
RS
I
7
GND
3
OUT
Figure 1
analog microelectronics
Analog Microelectronics GmbH
An der Fahrt 13, D – 55124 Mainz
Internet: www.analogmicro.de
Phone: +49 (0)6131/91 073 – 0
Fax:
+49 (0)6131/91 073 – 30
E–Mail: info@analogmicro.de
April 99
1/10
Rev. 2.1
AME [ ANALOG MICROELECTRONICS ]
