Datasheet
Industrial V/I Converter and Protector IC
AM462
Analog Microelectronics GmbH
An der Fahrt 13, D – 55124 Mainz Oktober 2007 – Rev.2.5 -Page 10/20
Phone: +49 (0)6131/91 073-0
Fax: +49 (0)6131/91 073-30
Internet:
http://www.analogmicro.de
Email: info@analogmicro
.de
The working range resulting from Equation Fehler! Verweisquelle konnte nicht gefunden
werden. is described in Figure 4. Example calculations and typical values for the external
components can be found in the example applications from page 13 onwards.
Using OP2 as a current source
The additional operational amplifier OP2 can easily be connected up as a constant current source.
Using the circuit in Figure 5 the following applies:
Example : OP2 as courrent source
SETSET
BG
S
RR
V
I
V27.1
==
(9)
The bridge symbol represents the component to be supplied with current (e.g. a piezoresistive
sensing element or temperature sensor).
A supply current of I
S
= 1mA is to be set. Using Equation Fehler! Verweisquelle konnte nicht
gefunden werden. the following value is calculated for external resistor R
SET
, which in turn
stipulates the size of the current:
Ω=== k27.1
mA1
V27.1
S
BG
SET
I
V
R
V
BG
AM462
OP2
1
R
SET
OP2 connected as
current source
2
I
S
Figure 5: Using OP2 as a constant current source