NPC CF8223A Datasheet

µ m × 90 µ

SM8223A

NIPPON PRECISION CIRCUITS INC.

FSK Decoder and DTMF Receiver IC

OVERVIEW

The SM8223A is a FSK (Frequency shift keying) decoder and DTMF (Dual tone multi-frequency) receiver IC.
It is fabricated using a CMOS process and features a power-down function for low power dissipation opera­tion. The FSK decoder and DTMF receiver have the same performance characteristics as dedicated ICs that
perform the same functions, with the added benefit of an FSK decoder/DTMF receiver auto-select function
using the telephone tip/ring input signal. It also features a ring (call signal) signal detection circuit, making for
easy construction of low power dissipation, high-performance analog telephone-related applications.

FEATURES

■

Both FSK signal caller-ID information services

PINOUT

(Top view)

and DTMF signal caller-ID information services
supported

■

FSK decoder/DTMF receiver auto-select function

■

Ring (call signal) signal detection circuit built-in

■

Serial I/O

■

Input gain adjustment circuit built-in

■

Power-down mode

■

Single supply operation: 3.0V ± 10%

■

3.579545MHz external crystal oscillator fre­quency

■

Molybdenum-gate CMOS process

TIP

RING

GS

AGND

RDIN

RDRC

RDET

PDWN

1

SM8223AP

8

16

9

VDD
DV
DOUT
FSK/DTMF
IC
OSCIN
OSCOUT
GND

APPLICATIONS

1

■

Telephones, fax machines and modems that sup­port caller-ID information services

■

Adapters for caller-ID information service func­tions

■

Telephones, fax machines and modems that sup­port remote operation functions

ORDERING INFORMATION

De vice Pack ag e

SM8223A 16-pin DIP

CF8223A Chip

PINOUT

(Unit: µ m)

GS

AGND

RDIN

RDRC

(0, 0)

RING TIP VDD DV

PDWN GND OSCOUT

RDET

Pad size : 9 0

m

1. Auto-select function operates if the FSK signal conforms to the Bellcore GR-30-CORE standard.

(2810, 3160)

DOUT

FSK/DTMF

IC

OSCIN

NIPPON PRECISION CIRCUITS—1

PACKAGE DIMENSIONS

(Unit: mm)

19.05

SM8223A

6.35

7.49 to 8.13

8.13 to 9.40

0.25

3.18 3.30

BLOCK DIAGRAM

Differential

Amplifier

TIP

RING

GS

FSK/DTMF

Discriminator

Logic

2.54

2.54 0.46 1.52

FSK/DTMF

FSK Decoder

Band Pass

Filter

High Group

Filter

Dial Tone

Filter

Low Group

Filter

3.68 to 4.32

0.38 to 1.02

FSK

Decoder

Logic

DTMF

Decoder

Logic

DV

DOUT

AGND

Bias

Circuit

GNDVDD PDWN

DTMF Receiver

OSC Ring Detect

OSCIN OSCOUT RDIN

RDRC RDET

NIPPON PRECISION CIRCUITS—2

µ

PIN DESCRIPTION

SM8223A

Number Name I/O Function

1 TIP I Tip input. Connected to the telephone line through a protection circuit 1046 2934
2 RING I Ring input. Connected to the telephone line through a protection circuit 63 8 2934

3GSO

4 AG N D O Analog ground output. Inter nal reference voltage (V

5 RDIN I

6 RDRC

7 RDET

8PDWNI

9 G ND – Ground. Connected to the system ground potential. 1634 226

10 OSCOUT O

11 OSCIN I

12 I C I Test input. Tied LOW for normal operation. 2634 1550

13 FSK/DTMF

14 DOUT O

15 D
16 V D D – Supply 1612 2934

V O Data trigger output. Data is output on DOUT when this pin goes LOW. 2211 2934

Input-stage amplifier gain-select output. Used to adjust the gain of the input­stage amplifier.

/2) output level 17 6 1954

DD

Ring detector input. Used for line reversal and ring signal detection.
Connected for ring detection of attenuated ring signals.

Ring detector RC terminal. Connected to an RC network which sets the ring

I/O

detector delay time.
Ring detector output. RDRC

O

output when ring signal is detected.
Pow er-down control input. LOW-level for normal operation. HIGH-level for

pow er-down state. In the pow er-down state, pins AGND, OSCOUT, DOUT,
and DV are HIGH.

Cr ystal oscillator output. The cr ystal oscillator element is connected between
this pin and OSCIN.

Crystal oscillator input. The crystal oscillator element is connected between
this pin and OSCOUT.

FSK/DTMF discriminator output. HIGH-level output when receiving FSK

O

signal, and LOW -level output when receiving DTMF signal.
Demodulator output. Demodulated FSK or DTMF signal output. HIGH-level

output in pow er-down state.

-input Schmitt-trigger buffer output. L OW -level

Pad dimensions (

XY

176 2665

176 1534

176 492

596 226

1063 226

2053 226

2634 506

2634 1942

2634 2623

m)

NIPPON PRECISION CIRCUITS—3

−

−

−

° C

∆

−

−

° C

SM8223A

SPECIFICATIONS

Absolute Maximum Ratings

GND = 0V

Parameter Symbol Rating Unit

Supply voltage range V
Input voltage range V
DC input current I
Storage temperature range T

Recommended Operating Conditions

GND = 0V

−

−

DD

IN

IN

stg

0.5 to 5.0 V

0.3 to V

+ 0.3 V

DD

±10 m A

40 to 125

Parameter Symbol Condition

Supply voltage V
Clock frequency f
Clock frequency accuracy
Operating temperature T

DC Electrical Characteristics

V

= 3.0V ± 0.3V, GND = 0V, f

DD

Parameter Symbol Condition

Supply current consumption I

Power-down state current I

PD WN, RDIN, RDRC LOW -level
input voltage

PD WN, RDIN, RDRC

HIGH-level

input voltage
OSCIN LOW-level input voltage V
OSCIN HIGH-level input voltage V
DOUT, DV, RDET, FSK/DTMF LOW -

level output current

V, RDET, FSK/DTMF HIGH-

DOUT, D
level output current

P DWN, RDIN input leakage current I
RDRC output leakage current I

CLK

DPD

V

V

I

DD

CLK

f

C

a

= 3.579545MHz, T

P DW N = 0V, RDIN = 0V,

DD

IL1

IH1

IL2

IH2

I

OL

OH

IN

OFF

RDRC = 0V, all other inputs
open

PDWN = V
RDRC = 0V, all other inputs
open

When external clock input – – 0.3V
When external clock input 0.7V

Rating

min typ max

2.7 – 3.3 V
– 3.579545 – MH z

0.1 – +0.1 %
20 – 85

= − 20 to 85 ° C unless otherwise noted.

a

Rating

min typ max

– – 4.5 mA

, RDIN = 0V,

DD

––15µA

– – 0.3V

0.7V

DD

DD

––V

––V

2––mA

––

1– 1µA

––1µA

Unit

Unit

DD

DD

0.8 m A

V

V

NIPPON PRECISION CIRCUITS—4

AC Electrical Characteristics

FSK decoder

V

= 3.0V ± 0.3V, GND = 0V, f

DD

CLK

SM8223A

= 3.579545MHz, T

− 40 −

−

−

Ω

= − 20 to 85 ° C unless otherwise noted.

a

Parameter Symbol Condition

Detection sensitivity Typical application circuit

Ma rk signal and SPACE

Noise reduction ratio

signal are same level.
Noise: Random noise from
200Hz to 3400Hz.

min typ max

20 – – d B

Rating

Unit

37.5 0 d B m

DTMF receiver

V

= 3.0V ± 0.3V, GND = 0V, f

DD

Parameter Symbol Condition

Detection frequency deviation
Non-detection frequency deviation ±3.5 – – %
Detection sensitivity
Non-detection sensitivity ––
Signal level error
High-frequency rejection ratio – 1 8 – d B
Noise rejection ratio –12–dB
Dial tone rejection ratio –20–dB

1. Input signal is up to V

DD

level.

= 3.579545MHz, T

CLK

Typical application circuit

Typical application circuit

= − 20 to 85 ° C unless otherwise noted.

a

Rating

min typ max

±1.5% ± 2 – – Hz

32.0 – 0.0 dB m

50.0 dB m

––6dB

1

Unit

Input-stage amplifier Characteristics

V

= 3.0V ± 0.3V, GND = 0V, f

DD

Parameter Symbol Condition

Input leakage current I
Input resistance R
DC open-loop voltage gain A
Unity gain frequency f
Load capacitance C
Load resistance R

= 3.579545MHz, T

CLK

IN

IN

VOL

C

L

L

= − 20 to 85 ° C unless otherwise noted.

a

Rating

min typ max

––1µA
–1–M

30 – – d B
80 – – kHz

– – 100 pF

50 – – k Ω

Unit

NIPPON PRECISION CIRCUITS—5