RATIOMETRIC VOLTAGE TRANSMITTER
APPLICATION FOR OUTPUT VOLTAGE 0.5...4.5V
AM417
R
TCO1
R
TCO2
2
9R
I
BR
AM417
V
CC
8
C
1
R
2
T
1
C
2
R
3
V
S
OP
1R
R
S
R
S
R
S
R
S
4
V
IN
5
R
O1
3
IA
Output
Stage
7
V
OUT
C
3
R
O2
R
TCS
6
1
R
4
R
1
Ground
Figure 5
The current application shows the basic functions of the AM417. With the given values of the ex-
ternal components (see
List of External Components)
the following application features are ad-
justed:
•
V
IN
= 100mV
•
G
=
G
IA
G
OUT
= 40
•
V
OUT
= 0.5 – 4.5V
•
I
OUT
= +10mA – 0.25mA
•
I
BR
= 1mA (ratiometrical supply current for the pressure transducer)
LIST OF EXTERNAL COMPONENTS
Symbol
T
1
R
1
R
2
R
3
R
4
R
S
R
TCS
R
O1
,
R
O2
R
TCO1
,
R
TCO2
C
1
C
2
C
3
±
10%
±
10%
Description
BCW68H, BC557C (or similar)
I
BR
= 1 mA
I
OUT
= 10mA min (100°C)
Value
low drop, high
β
at10mA
500
15
500
1.5
3.0 (typ.)
10 – 120
0 – 500
0.1 – 10.0
330
4.7
1.0
Unit
PNP
Ω
Ω
Ω
kΩ
kΩ
kΩ
Ω
MΩ
nF
nF
nF
}
Span (Gain adjustment)
V
OUT
=
R
3
/ (R
3
+
R
4
)
G
typical transducer resistor
TC
span compensation
Offset adjustment
TC
offset adjustment
The information provided herein is believed to be reliable; however, Analog Microelectronics assumes no responsibility for inaccuracies or omissions. Analog Microelectronics assumes no responsibility
for the use of this information, and all use of such information shall be entirely at the user's own risk. Prices and specifications are subject to change without notice. No patent rights or licences to any of
the circuits described herein are implied or granted to any third party. Analog Microelectronics does not authorise or warrant any Analog Microelectronics product use in life support devices and/or
systems.
analog microelectronics
April 99
6/6
AME [ ANALOG MICROELECTRONICS ]
