A.C. Characteristics

Ta=25

°C

Symbol

Parameter

Test Conditions

Min.

Typ.

Max.

Unit

Conditions

Low Tone Frequency

5V

¾¾

2130

¾

Hz

High Tone Frequency

5V

¾¾

2750

¾

Hz

Frequency Deviation Acceptance

5V

Range within which,

tones are accepted

¾¾

±0.7

%

Frequency Deviation Reject

5V

Range outside of which,

tones are rejected

±2.5

¾¾

%

Acceptable Signal Level per Tone

5V

No speech

-33

¾

0

dBm

Reject Signal Level per Tone

5V

No speech

¾-36

¾

dBm

Twist Accept Limit

5V

¾¾

±7

¾

dB

Signal to Noise Ratio

5V

¾¾

-19

¾

dB

Present Detect Time

5V

¾¾

55

¾

ms

Clock (System Frequency)

Ta=25

°C

Symbol

Parameter

Test Conditions

Min.

Typ.

Max.

Unit

Conditions

Clock Input Frequency

5V

¾

3.5759 3.5795 3.5831

MHz

Clock Input Rising Time

5V

¾¾

¾

110

ns

Clock Input Falling Time

5V

¾¾

¾

110

ns

Clock Input Duty Cycle

5V

¾

40

50

60

%

HT9033

Rev. 1.00

3

May 22, 2006

Functional Description

Power Down Mode

If PDWN pin= 1, the HT9033 is in reset status and the

CAS detector is at power down mode, all function is dis-

able. The oscillator circuit will be stop.

If PDWN pin= 0, CAS detector is activated.

CAS Detector Output Signal

The output pin DO is CMOS structure. At the normal sta-

tus (CAS tone is not presence), the DO pin output low.

When the CAS tone is detected, the DO pin will output

high level.

CAS Detector Timing

C A S T o n e

D O

C o n d i t i o n 1 ( S t a n d a r d C A S T o n e ) :

C o n d i t i o n 2 ( C o n t i n u o u s C A S T o n e ) :

C A S T o n e

D O

8 0 m s

Parameter

Note

Min.

Typ.

Max.

Unit

CAS Detecting Time

¾

55

¾

ms

DO Off Time

¾

8

¾

ms

DO Duration Time

¾

145

¾

ms

DO Duration Off Time

¾

48

¾

ms