Pin Assignment

Pin Description

Pin Name

I/O

Description

Power Inputs

VDD

¾

Power-VDD is the input power for the internal logic.

VSS

¾

Ground-VSS is ground connection for the internal logic.

PDWN

I

A logic

²1² on this pin puts the chip in power down mode. When a logic ²0² is on this pin, the

chip in power up mode. This is a Schmitt trigger input.

Clock

X1

I

A crystal or ceramic resonator should be connected to this pin and X2.

This pin may be driven from an external clock source.

X2

O

A crystal or ceramic resonator should be connected to this pin and X1.

Ring Detections

RDET1

I

It detects ring energy on the line through an attenuating network and enables the oscillator and

ring detection. This is a Schmitt trigger input.

RDET2

I

It couples the ring signal to the precision ring detector through an attenuating network.

RDET=

²0² if a valid ring signal is detected. This is a Schmitt trigger input.

RTIME

I/O

An RC network may be connected to this pin in order to hold the pin voltage below 2.2V be-

tween the peaks of the ringing signal. This pin controls internal power up and activates the par-

tial circuitry needed to determine whether the incoming ring is valid or not. The input is a

Schmitt trigger input. The output cell structure is an NMOS output.

FSK Signal Inputs

TIP

I

This input pin is connected to the tip side of the twisted pair wires. It is internally biased to 1/2

RING

I

This input pin is connected to the ring side of the twisted pair wires. It is internally biased to 1/2

Detection Results

RDET

O

This open drain output goes low when a valid ringing signal is detected. When connected to

PDWN pin, this pin can be used for auto power up.

CDET

O

This open drain output goes low indicating that a valid carrier is present on the line. A hyster-

esis is built-in to allow for a momentary drop out of the carrier. When connected to PDWN pin,

this pin can be used for auto power up.

DOUT

O

This pin presents the output of the demodulator when chip in power up mode. This data stream

includes the alternate

²1² and ²0² pattern, the marking, and the data. At all other times, this pin

is held high.

DOUTC

O

This output presents the output of the demodulator when chip in power up mode and when an

internal validation sequence has been successfully passed. This data stream does not include

the alternate

²1² and ²0² pattern. This pin is always held high.

TEST

O

Output pin for testing purposes only.

NC

¾

No connection

HT9032C/HT9032D

Rev. 1.40

2

September 30, 2002

N C

T E S T

T I P

V D D

R T I M E

R D E T 1

X 2

P D W N

V S S

R I N G

C D E T

R D E T

X 1

R D E T 2

D O U T C

D O U T

H T 9 0 3 2 C

1 6 D I P - A / S O P - A

1

2

3

4

5

6

7

8

1 6

1 5

1 4

1 3

1 2

1 1

1 0

9

D O U T

T I P

V D D

R I N G

P D W N

X 2

V S S

X 1

1

2

3

4

8

7

6

5

H T 9 0 3 2 D

8 D I P - A / S O P - A