CAV424 - C/U transducer IC

with adjustable output voltage

Analog Microelectronics GmbH

An der Fahrt 13, D – 55124 Mainz

July 2007 - Rev 1.2 - Page 5/16

Phone: +49 (0)6131/91 073-0

Fax:

+49 (0)6131/91 073-30

Internet:

http://www.analogmicro.de

Email: info@analogmicro.de

superimposed onto the actual direct voltage signal.

Oscillator function

Figure 3).

I

V

R

OSC

M

OSC

"

(1)

The oscillator frequency

as:

OSC

OSC

OSC

OSC

C

V

I

f

#

$

#

"

2

(2)

(2)

where

the thresholds of the internal oscillator

(

defined via internal resistors in the IC and

has a value of 2.1V @

Figure 3). The oscillator frequency can

thus be specified by the choice of

given in

Table 1.

Capacitive integrators

The built-in capacitive integrators function works in the same way as the oscillator. One difference

lies in the discharge time, which here is half the length of the charge-up period. Furthermore, the

minimum oscillator voltage for the integrators is internally clamped to a value of

(see

Figure 4).

V

OSC,HIGH

time

t

V

OSC,LOW

V

OSC

T

2T

T

2

V

OSC

Figure 3: Oscillator voltage curve