OKI MSM7715GS-2K Datasheet

E2A0030-16-X1

¡ Semiconductor MSM7715

¡ Semiconductor

This version: Jan. 1998

Previous version: Nov. 1996

MSM7715

Multi-Function Telecommunication LSI

GENERAL DESCRIPTION

The MSM7715 is a signal transmitting and receiving LSI device for applications such as telemeters. The MSM7715 uses a no-ringing communication mode. Built-in functions includes a 300 bps full-duplex modem complying with ITU-T V.21, a DTMF signal (PB signal) generator and receiver, and a call progress tone (CPT) detector. The answer tone (1650 Hz) generation can be accomplished with the built-in modem. A meter terminal can be configured using this transmitting and receiving device along with the meter, NCU, and controller.

FEATURES

• 3 V power supply. (Voltage range is 2.5 V to 3.6 V.)

• Selectable modes, including DTMF signal sending mode, DTMF signal receiving mode, and V.21 modem answer/originate mode.

• For DTMF signal reception, support for normal detection mode or high-speed detection mode.

• For call progress tone detection, support for rectangular wave output or detection output.

• DTMF signal receiving output, which is in a 3-state mode, is able to be connected externally with the DTMF signal sending 4-bit input.

• Analog loopback test and remote digital loopback test supported.

• Dedicated pins for modem sending/receiving data, carrier detection, sending request, and call progress tone detection.

• Independent external adjustment of the analog signal using the modem signal and DTMF signal.

• External adjustment of the carrier detection level.

• Internal 3.579545 MHz crystal oscillation circuit.

• Power-down mode

• Package: 44-pin plastic QFP (QFP44-P-910-0.80-2K) (Product name : MSM7715GS-2K)

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BLOCK DIAGRAM

DT1 DT2 DT3 DT4 SP DTTIM

CP CPW

CD

RD TD

RS

CLK X2 X1

MODE1 MODE2 MODE3 ICTA ICTB

TEN

DTG1 DTG2 DTG3 DTG4

AIN

AOUT

GAT2 GAT1

MOD

VR1

VR2

SGO

SGC

DTO

PON

V

DD

GND

Mode Select

&

Test

FSK Modem

Carrier

Detector

CPT

Detector

DTMF

Receiver

2765 Hz

BEF

PreLPF

Smooth

Voltage

Ref.

SG

DTMF

Generator

+ –

– +

*

* * * * *

Power ON

+3 V

0 V

4 dB

Note) DT1 to DT4 :

3-state outputs

* :

Input with

pull-up resistor

*

¡ Semiconductor MSM7715

PIN CONFIGURATION (TOP VIEW)

DTG343DTG242DTG141GND40VR239VR138DTO37MOD36GAT235GAT134SGC

44

DTG4

TEN

TD

RS

CPW ICTA ICTB

DTTIM MODE1 MODE2 MODE3

10 11

1 2 3 4 5 6 7 8 9

12

13X214NC15

X1

16RD17CD18CP19

CLK

DT120DT221DT322DT4

33 32 31 30 29 28 27 26 25 24 23

NC SGO AIN NC V

DD

NC AOUT NC NC

PON

SP

NC : No connect pin

44-Pin Plastic QFP

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¡ Semiconductor MSM7715

PIN DESCRIPTION

Pin No. I/OName

DTG4

TEN 2

TD 3

RS 4

CPW 5

ICTA 6 ICTB 7

DTTIM 8

MODE1 9 MODE2 10 MODE3 11 X1 12 X2 13 CLK 15

Description

1

I*

Input for specifying the DTMF code to be sent. Input for controlling output of the DTMF signal. (Transmit enable)

I*

DTG1 to DTG4 are latched at the falling edge of TEN and the DTMF signal is output when “0” is input. See Fig. 2.

Input for data to be sent to the modem. Input the data string at a speed of 300 bps

I*

or lower. Input for controlling the modem sending output. (Request to send)

I*

The sending signal is output when “0” is input.

Input for selecting the output waveform from the call progress tone detector. When "1" is input, a rectangular wave that is synchronized with the input signal is

I*

output from the CP. When "0" is input, presence of detected signal is output from the CP pin. See Fig.3.

Inputs for testing. Leave them open or connect them to V

I*

Input pin for controlling the detection timing of the DTMF receiver.

I*

When “0” is input, the high-speed detection mode is selected.

I*

Input for selecting the operation mode. See Table 1.

I

Input and output connected to the crystal oscillator. See “Oscillation Circuit” in the Functional Description.

O

3.579545 MHz clock output

O

DD

.

RD 16

CD 17

CP 18

DT1 19 DT2 20 DT3 21 DT4 22

SP 23

PON 24

AOUT 27

Output for serial data received by the modem. It is held in the marked state

O

(“1”) when the carrier detector (CD) does not make detection. Output for the carrier detector. “0” means detection, while “1” means

O

non-detection. Output for call progress tone (CPT) detection. When the CPT is detected,

O

the waveform selected by the CPW pin is output. See Fig. 3.

Outputs for the code of the received DTMF signal. In a mode other than the

O

DTMF receiving mode, these pins are in a high-impedance state.

Output for presenting the DTMF signal receiving data. “1” means that the DTMF

O

signal is being received. Latch DT1 to DT4 at the rising edge of SP. See Fig. 1.

Input for controlling power-on. When “1” is input, all lines of this device enter the

I*

power down state, and then the operation of each funciton stops and the receiver timer is reset.

Analog signal output. The DTMF signal or modem sending signal is output.

O

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¡ Semiconductor MSM7715

Pin No. I/OName

V

DD

29

—

AIN 31 I

SGO 32 O

SGC 34

—

GAT1 35 I GAT2 36 O MOD 37 O DTO 38 O

VR1 39 O

VR2 40 I GND 41

— DTG1 42 DTG2 43 DTG3 44

Description

Power supply. Supply +2.5V to 3.6V. Input for the analog receiving signal.

Output for the signal ground voltage. The output voltage is 1/2 V Connect a capacitor of 0.1 mF or more between SGO and GND.

Pin for connecting the capacitor of the signal ground voltage generating circuit. Connect a capacitor of 1 mF or more between SGC and GND.

Input for the sending output level-adjusting amplifier. Output for the sending output level-adjusting amplifier. Output for the sending modem signal. Output for the DTMF signal.

Output for the reference voltage generating circuit. The potential difference between VR1 and SGO is approximately +0.75 V.

Input for external adjustment of the modem’s carrier detection level. Ground.

Inputs for specifying the DTMF code to be sent.

I*

Data is latched at the falling edge of TEN.

DD

.

Note: Digital inputs that are pulled up internally by a high resistance.

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¡ Semiconductor MSM7715

ABSOLUTE MAXIMUM RATINGS

Parameter Condition UnitRating

Power Supply Voltage Input Voltage Storage Temperature

Symbol

V

DD

V

I

T

STG

Ta = 25°C

With respect to GND

—

RECOMMENDED OPERATING CONDITIONS

Parameter Min. Unit

Power Supply Voltage Operating Temperature Range

Input Voltage

Input Clock Frequency X1/X2 Load Capacitance SGC Bypass Capacitance SGO Bypass Capacitance V

Bypass Capacitance

DD

Oscillation Frequency Frequency Deviation

Temperature Characteristics

V

DD

T

op

V

IH

V

IL

f

CLK

C1, C2

C3 C6 C5 — —

—

Crystal

Equivalent Series Resistance

—

ConditionSymbol Typ. Max.

— —

—

Against 3.579545 MHz

— — — 0.1 — — — —

At 25°C ±5°C

At –40°C to +85°C

—

–0.3 to 7

–0.3 to VDD + 0.3

–65 to +150

2.5

3.0

–40

0.8 V

DD

0

–0.1

— —

10 —

3.579545

–100

–50

—

— — — — 12

—

V V

°C

3.6 +85 V

DD

0.2 V +0.1

—

1

—

V

°C

V

DD

% pF

mF

—

MHz

—

+100

ppm

+50

90

W

Load Capacitance

—

16

—

pF

ELECTRICAL CHARACTERISTICS

DC Characteristics

= 2.5 V to 3.6 V, Ta = –40°C to +85°C)

(V

DD

Parameter Min. Unit

I

Power Supply Current

Input Current

*1

Output Voltage

*2

I I

V V V V

DD1

DD2

DDS

I

IH

I

IL

OH1

OL1

OH2

OL2

PON = "0"

V

= V

IH

DD

VIL = 0 V

CLK C

£10 pF

L

Notes: *1 The following pins have an internal pull-up resistor. : DTG1 to DTG4, TEN, TD, RS,

CPW, ICTA, ICTB, DTTIM, MODE1 to MODE3, and PON

*2 RD, CD, CP, DT1 to DT4, and SP

ConditionSymbol Typ. Max.

Modem mode DTMF mode Power-downPON = "1"

— —

— –10 –50

V

*2

IOH = –100 mA I

= 100 mA

OL

I

= –100 mA

OH

I

= 100 mA

OL

– 0.1

DD

0

0.9 V 0

DD

3

2.4 1

—

–10

— — — —

6

5 20 10 10

V

DD

0.1

V

DD

0.1 V

mA

V

DD

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¡ Semiconductor MSM7715

AC Characteristics (DTMF)

(

VDD = 2.5 V to 3.6 V, Ta = –40°C to +85°C)

Parameter Min. Unit

V

Transmit Level

Transmit Signal Level Relative Value

V

DTTL

DTTH

DTDF

AOUT, R1 = R3

High-group tone/low-group tone

ConditionSymbol Typ. Max.

Low-group tone High-group tone

–16.5 –15.5

0

–14.5 –13.5

–12.5 –11.5

1

2

dBm

*1

dB

Transmit Frequency Deviation

Transmit Signal Distortion Rate

DTG1 to DTG4 Input Data Setup Time

DTG1 to DTG4 Input Data Hold Time

Receive Detect Level Receive Reject Level

Receive Frequency Detect Band

Receive Frequency Reject Band

Allowable Receive Level Difference

Allowable Receive Noise Level ratio

f

DDT

THD

t

SDT

t

HDT

V

DETDT

V

REJDT

f

DETDT

f

REJDT

V

TWIST

V

N/S

With respect to the nominal frequency

Harmonics/Fundamental frequency

DT

See Fig. 2.

For each single tone For each single tone

With respect to the nominal frequency

High-group tone/low-group tone

Noise (0.3 kHz to 3.4 kHz) level/tone level

–1.5

—

250

–46

—

±3.8

–6

—

— —

—

–12

+1.5

–23

—

–10 –60

±1.5

—

+6

—

%

dB

ns

dBm

*1

%

dB

Dial Tone Reject Ratio

Signal Repetition Time

Tone Time for Detect

Tone Time for No Detect

Output Delay Time

Interdigit Pause Time

Acceptable Drop Out Time

SP Delay Time

Output Trailing Edge Delay Time

V

REJ400

t t t t

t t

t

G11

t

G12

t

G21

t

G22

t t t t

t

SP1

t

SP2

t t

D1

D2

C1

C2

S1

S2

P1

P2

B1

B2

380 Hz to 420 Hz

DTTIM = "1" DTTIM = "0" DTTIM = "1"

37

120

70 49

— — — —

See Fig. 1

DTTIM = "0"

I1

I2

Normal condition *2 Just after mode change *3

DTTIM = "1" DTTIM = "0" DTTIM = "1" DTTIM = "0" DTTIM = "1" DTTIM = "0" DTTIM = "1" DTTIM = "0" DTTIM = "1" DTTIM = "0" DTTIM = "1" DTTIM = "0"

> 80 ms

t

S

> 44 ms

t

S

DTTIM = "1" DTTIM = "0"

34 — — 30 20 42

30 21 — —

6

1 21 15 27

— — — 45 32 4830 77 3520 62 — — — —

8

1.7 29 21

— 24

9

57

ms

— — 10

3

10

3

35

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