ELAN EM91240CK, EM91240BP, EM91240AP Datasheet

GENERAL DESCRIPTION

The EM91240 is a series of tone/pulse switchable dialers that is composed of T/P dialer and T/P dialer with
40-set memories. The EM91240 series provides necessary functions of telephone set for application in any
environment, such as Pulse dialing, Tone (DTMF) dialing, Handfree dialing, keying tone , mute and pulse
mute functions. Beside this, SDO (Serial Data Output) functions is provided in advance version that is designed
to drive LCD driver and voice synthesizer. In this application, the dialing numbers can be displayed on LCD
screen with EM32100 ( or EM32116 ).

FEATURES

•Tone/Pulse switchable.

• Wide operating voltage from 2.0 V to 5.5 V.

•Low operating current, 0.15 mA (Pulse) and 0.3 mA (Tone) typically.

•Adding resistor on keyboard scan pin that can select many telephone specifications, such as : Pulse rate,
M/B ratio, Flash time, Pause time, P-T wait time and keyboard type.

•SDO function supports LCD driver and voice synthesizer to indicate dialing numbers.

•Handfree function provides on-hook dialing and speakerphone application.

•40-set three touch repertory memory, each one can store data up to 16 digits.

•A 32-digit LNB (last number) redial memory.

•A 32-digit SAVE redial memory.

•Keytone function provides rapidly keying recognition.

•Pulse mute function supports pulse dialing application.

•Using 3.579545 MHz crystal or ceramic resonator.

•Package forms: PDIP, skinny.

EM91240 SERIES

TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE

TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE

EM91240 SERIES

ORDERING INFORMATION

Versions list

VERSION LNB KT SAVE HF SDO(LCD) PMUTE
EM91240A √√√ √

EM91240B √√√ √ √
EM91240C √√√ √ √ √

* This specification are subject to be changed without notice.

10.1.1997

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EM91240

Pin Assignment

EM91240 SERIES

TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE

COL5

COL4/KT

COL3
COL2
COL1

XOUT

XMUTE

Keyboard Arrangement

Type A Type B

COL1
ROW1
ROW2
ROW3
ROW4

1
4
7

*/T

EM91240AP

1
2
3
4
5
6

XIN

7
8
9

VSS

COL3

COL2

2
5
8
0

EM91240BP

20

1

18

PM

17

PO

16

ROW4

15

ROW3

14

ROW2

13

ROW1

12

HKS

11

VDD

10

DTMF

COL5

COL4/KT

COL3
COL2
COL1

XIN

XOUT

XMUTE

VSS

HFI

2
3
4
5
6
7
8
9

10

PM

19

PO

18

ROW4

17

ROW3

16

ROW2

15

ROW1

14

HKS

13

VDD

12

DTMF

11

HFO

EM91240CK

SDO

NC

COL5

COL4/KT

COL3
COL2
COL1

XIN

XOUT

XMUTE

VSS

HFI

SAVE

F
A

RD/P

COL5

ST

COL4/KT
3
6
9
#

22

1
2
3
4
5
6
7
8

9
10
11

21
20
19
18
17
16
15
14
13
12

ROW1
ROW2
ROW3
ROW4

PM
PO
ROW4
ROW3
ROW2
ROW1
HKS
VDD
DTMF
HFO

COL1

COL2

COL3

1

2

4

5

7

8

*

0

COL4/KT
3
6
9
#

SAVE

F
A

RD/P

COL5

P→T

ST

FUNCTIONAL BLOCK DIAGRAM

HFO

SDO

COL1
COL2
COL3

COL4/KT

COL5

XIN

XOUT

ROW1

~

ROW4

* This specification are subject to be changed without notice.

Keyboard

interface

(column)

Oscillator

Keyboard

interface

(Row)

Output circuit

Timing/Control circuit

VDD

PM

Memory

(Melody)

Input circuit

HKS HFI

XMUTE

VDD

Row/Column

programming counter

latch

&

decoder

Pulse

generator

D/A

converter

PO

DTMF

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EM91240 SERIES

TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE

PIN DESCRIPTIONS

Symbol Function

ROW1~ROW4 Keyboard scan pins of row group. In idle state (HKS is “High” and HFO is “Low”),

these pins stay “High impedance” level to prevent power consumption. Otherwise,
these pins switch to “High” level for detecting keyboard entry. These pins will output
600 Hz signal while keyboard is scanning.

COL1~COL3 and COL5 Keyboard scan pins of column group. In idle state, these pins stay “High impedance”

level. Otherwise these pins switch to “Low” level for detecting keyboard entry. These
pins will output 600 Hz signal while keyboard is scanning.

COL4/KT The fourth column group pin of the keyboard that also provides the keytone output

. Normally, this pin stays “Low” level for detecting keyboard entry. After a valid
keyboard entry, this pin will output keying confirmation tone that is 600 Hz signal and
30 ms duration. While DTMF output, the key tone will be disabled. To prevent signal
interference, while DTMF issue, it will disable key tone output except function key.

XIN and XOUT Oscillator input and output pins. A 3.579545 MHz crystal or ceramic resonator must

be crossed connection to XIN and XOUT pins which generate system clock.

XMUTE The Tone/Pulse MUTE signal output pin that is NMOS open-drain output structure.

This pin will switch to “Low” level during Tone/Pulse dialing.
Otherwise, this pin stays “High impedance” level.

V

and V

DD

SS

HFI Handfree inputs pin which accepts falling edge signal to turn “on” or turn “off”

HFO Handfree outputs pin that is designed to control telephone line for on-hook dialing or

DTMF The DTMF (Dual Tone Multi-Frequency) output pin. Normally, this pin stays“Low”

HKS Control signal inputs pin that is corresponding hook switch status. When handset was

PO Pulse signal outputs pin that is NMOS open-drain output structure. Normally, this pin

PM Pulse signal outputs pin that is CMOS inverter output structure. Normally, this pin

SDO SDO function output that is NMOS open-drain structure. When there is a valid entry

NC No connection.

Positive and negative power supply input pins. Recommended operating voltage from

2.0Vdc to 5.5Vdc.

handfree function. This pin is hysteresis input structure and built-in pull up resistor
(typically 200 Kohms).

control speakerphone circuit for handfree conversation. When handfree function is
executed, this pin will switch to“High”. Otherwise, this pin stays “Low” level.

level. In Tone dialing mode, this pin will output DTMF signal that is corresponding
to keyboard 0..9, * and # keys.

left from cradle, this pin must be connected to “Low” level to operate all functions.
Otherwise, this pin must be connected to “High” level to disable all function and

prevent power consumption.

stays “High impedance” level. In Pulse dialing mode and keypad was entry. This pin
will output pulse trains signal that is corresponding to keyboard 0 .. 9 keys.

stays “Low” level. During pulse signal dialing or flash function executing, this pin will
switch to “High” level to control the external circuit.

on keyboard, this pin will output a serial data. This serial data is designed to drive LCD
driver to display dialing number on LCD screen or drive voice synthesizer to announce
dialing number to speaker.

* This specification are subject to be changed without notice.

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FUNCTION DESCRIPTIONS

Dialing signal selection

The EM91240 series incorporated a special keyboard scanning function that is connecting a resistor (typically
is 560 Kohms) on keyboard scan pin to select many telephone specifications. The specifications are described
as following :

a. Mode b. M/B ratio

ROW1 Mode ROW2 MBR (%)
R-Vdd 20 PPS NR 40:60

NR Tone R-Vss 33:66

R-Vss 10 PPS

c. Flash time d. DTMF signal

ROW3 ROW4 Tf (ms) COL1 Td (ms) Titp (ms)

NR NR 600 R-Vdd 90 90

NR R-Vss 100 NR 98 98
R-Vss NR 80 R-Vss 83 83
R-Vss R-Vss 300

e. Pause time and P-T wait time f. Keyboard operate type

COL2 Tp (sec) Tpt (ms) COL3 Type

NR 3.6 3.6 NR A
R-Vss 2.0 2.0 R-Vss B

EM91240 SERIES

TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE

Normal dialing

Directly keying digital key on keyboard which number can be dialing output and stored in LNB memory
automatically. Operating procedure described as follow :

• To select Pulse or Tone mode.

• Off-hook or turn on HF function.

• Keying d1, d2, .. , dn. The “d” expressed digital keypad that included 1~9, *, 0, #, P, and P→T keys. The “n”
expressed unlimited.

• The numbers d1, d2, .. , dn will be dialed out in Pulse or Tone mode as selection.

LNB redial memory

Storing:

In normal dialing mode, every digital key was entry which number will be stored in LNB memory
automatically. If entry digits are more than 32 digits, the redial function of LNB memory will be disabled.
Otherwise, these numbers stored in LNB memory can be redial output.

Redialing:

After normal dialing, directly keying
numbers that are stored into LNB memory will be dialed output.

F key (or On-Off hook once) and keying RD key on keyboard. The

SAVE redial memory

The SAVE meomry is designed in EM91240 series to support 32 digits capacity buffer for second redial,

* This specification are subject to be changed without notice.

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EM91240 SERIES

TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE

pager, Memory and other system applications.

Storing : EM91240 series support two operating methods to store numbers into SAVE redial memory.

Method 1

• To select Pulse or Tone mode.

• Off-hook (or turn on HF function), push

d1, d2, .. , dn. The numbers d1, d2, .. , dn will be dialed out in Pulse

or Tone mode as selection.

• After dn had been dialed out and push

[ST], Save key. If the keying numbers are more than 32 digits that
content of SAVE memory can not be updated. Otherwise, these numbers will be stored into SAVE memory.
In the [] key allows to be omitted.

Method 2

Off-hook (or turn on HF function), push ST, d1, d2, .. , dn, [ST], Save. If the keying numbers are not over 32
digits, the numbers d1, d2, .. , dn will be stored in SAVE redial memory automatically.

Dialing :

• To select Pulse or Tone mode.

• Off-hook (or turn on HF function), push Save key. The numbers stored in SAVE memory will be dialed out
in Pulse or Tone mode as selection.

Repertory memory

The EM91240 series incorporated several sets repertory memory and each one can store number up to 16 digits.
In memory storing, if stored numbers are more than 16 digits that only the previous 16 digits can be stored into
specific memory. Otherwise, these numbers can be stored entirely. After memory dialed out, the content of
LNB is keeping to current data.

Storing of 40 sets memory

Indirect (three-touch) operation

Off-hook (or turn on HF function), push
into memory location “n n”. The “n n” expressed digital number from 01 to 40.

Dialing (after memory dialed out, the content of LNB is keeping to current data)

Indirect (three-touch) memory

• To select Pulse or Tone mode.

• Off-hook (or Turn on HF function), push
location “n n” will be dialed out in Pulse or Tone mode as selection . The “n n” expressed digital number
from 01 to 40.

ST, d1, d2, .. , dn, ST, n, n. The numbers d1, d2, .. , dn will be stored

A, n , n key. The numbers that are stored in indirect memory

* This specification are subject to be changed without notice.

10.1.1997

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EM91240 SERIES

TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE

Pause (P) key operation

The Pause (P) key is designed to support pause operation in dialing duration. “P” key can be stored in memory
and it will occupy one digital position.

• To select Pulse or Tone mode.

• Off-hook (or turn on HF function), push
out as following sequence:

d1, d2, .. , dn, Tp, k1, k2, .. , kn.

d1, d2, .. , dn, RD/P, k1, k2, .. , kn . These numbers will be dialed

Pulse to Tone (*/T or P-T) key operation

The Pulse to Tone (*/T or P-T) key is designed to support toll dialing (long distance call) or PABX system
operation. The "*/T (or P-T)" key can be stored in memory and it will occupy one digital position.

• To select Pulse mode.

• Off-hook (or turn on HF function), push
out as following sequence:

d1, d2, .. , dn, */T, (or P-T) k1, k2, .. , kn. These numbers will be dialed

d1, d2, .. , dn, Tpt, k1, k2, .. , kn.

(pulse mode) (tone mode)

Flash (F) key operation

The Flash (F) key is designed to break telephone line temporarily. After F key is depressed, this dialer will send
a flash signal to break line 600 ms, 300 ms, 100 ms or 80 ms as ROW3 and ROW4 selection.

Handfree (HF) function

The handfree function is designed to support on-hook dialing and loudspeaker application which can be turn “on”
or “off” with falling edge signal from HFI pin. During handfree function is executed, the HFO pin is switched
to “high”. Otherwise the HFO pin stays “low” level.

Truth table

Operating state Input/Output pin level

HKS PO XMUTE PM HFO
(0) On-hook, idle state H F F L L
(1) Off-hook line L F F L L
(2) Off-hook, HF line L F F L H

(3) On-hook, HF line H F F L H

Note : F=floating (high impedance); H=logic “High”; L=logic “Low” level.

SDO (Serial Data Output) function

The SDO is serial data output which format is same as UART protocol. SDO function is designed to drive LCD
driver and voice synthesizer. So the dialing numbers can be display on LCD screen with EM32100 (or EM32116
). The SDO signal consists of two start bits, six data bits and two stop bits. Each bit time is about 3.9 ms (256 Hz)

and output sequences are following by start bits, data bits (LSB to MSB) and stop bits.

* This specification are subject to be changed without notice.

10.1.1997

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