Converter IC for Capacitive Signals
FEATURES
•
Wide Supply Voltage Range: 6...35V
•
Wide Operating Temperature Range:
–40°C...+85°C
•
High Detection Sensitivity of Relative
Capacitive Changes: 5% – 100%
•
Detection Frequency up to 2kHz
•
Adjustable Voltage Range:
0...5/10V, other
•
Reference Voltage Source: 5V
•
Protection against Reverse Polarity
•
Output Current Limitation
•
Adjustable with only two Resistors
CAV414
GENERAL DESCRIPTION
The CAV414 is an universal multipurpose in-
terface for capacitive sensors and contains the
complete signal processing unit on chip. The
CAV414 detects the relative capacitive change
of a measuring capacity to a fixed reference
capacity. The IC is optimised for capacities in
the wide range of 10pF to 2nF with possible
changes of capacity of 5% to 100% of the ref-
erence capacity.
The voltage output is formed by a high accu-
racy instrumentation amplifier in combination
with an operational amplifier.
With only a few external components, the
CAV414 is suitable for a great variety of ap-
plications including a zero compensation.
APPLICATIONS
•
•
•
•
•
Industrial Process Control
Distance Measurement
Pressure Measurement
Humidity Measurement
Level Control
DELIVERY
•
DIL16 packages (samples)
•
SO16(n) packages
•
Dice on 5“ blue foil
BLOCK DIAGRAM
COSC
12
Reference
Oscillator
CAV414
IA
OP
VCC
9
CX1
16
Integrator 1
Integrator 2
Signal Conditioning
VOUT
8
7
10
CX2
14
GAIN
GND
Voltage/Current
Reference
15
13
4
5
6
2
3
1
11
VREF
CL1
Figure 1
CL2
RL LPOUT VM
RCX1 RCX2 RCOSC
analog microelectronics
Analog Microelectronics GmbH
An der Fahrt 13, D – 55124 Mainz
Internet: http://www.analogmicro.de
Phone: +49 (0)6131/91 073 – 0
Fax:
+49 (0)6131/91 073 – 30
E–Mail: info@analogmicro.de
January 2001
1/6
Rev. 2.1
AME [ ANALOG MICROELECTRONICS ]
