CAV424 Datasheet, PDF (3/16 Pages) List of Unclassifed Manufacturers – Converter IC for Capacitive Signals

CAV424 - C/U transducer IC
with adjustable output voltage
FEATURES
! High detection sensitivity
! Wide capacitor measuring range:
5% – 100% relative to the reference
capacitor, 0.5pF to 1nF.
! Detection frequency of up to 2kHz
! Adjustable output offset
! Adjustable full scale output signal
! Differential output
! High voltage immunity
! Temperature output signal
! Wide temperature range:
-40°C...+105°C
! Supply voltage: 5V ± 5%
! Ratiometric output voltage
! Simple calibration (Excel program)
! RoHS compliant
BLOCK DIAGRAMM
GENERAL DESCRIPTION
CAV424 is an integrated C/V converter circuit
which contains full signal conditioning electro-
nics for almost any source of capacitive signal.
For measurement capacitor C_M CAV424
detects the relative change in capacitance !C_M
= C_M,_max– C_M,_min in relation to that of a given,
fixed reference capacitor C_R.
The IC has been optimized for reference
capacitors of between 10pF and 1nF where the
change in capacitance !C_M can be 5% to 100%
of the basic capacitance C_M,_min.
The differential voltage output has been
specially designed for connection to an A/D
converter. Together with the integrated
temperature sensor and a processor
calibratable systems can be assembled. A
simple Excel program simplifies the
dimensioning of CAV424.
CAV424
VTEMP
7
T Sensor
COSC
12
Reference
oscillator
CR
16
CM
14
Integrator 1
Integrator 2
RCR
2
RCM
3
RCOSC
1
VCC
11
Current reference
6 ^VM
Signal conditioning
LPOUT
5
10
GND
15
13 4
CL1
CL2 RL
Figure 1: Block diagram CAV424
Analog Microelectronics GmbH
An der Fahrt 13, D – 55124 Mainz
Phone: [phone]
Fax: [phone]
Internet:
http://www.analogmicro.de
Email: [e-mail]
July 2007 - Rev 1.2 - Page 3/16