1
EM91810A/B
TONE/PULES SWITCHABLE DIALER WITH LCD INTERFACE
* This specification are subject to be changed without notice.
10.1.1997
GENERAL DESCRIPTION
The EM91810A/B are Tone/Pulse switchable dialer which are fabricated in CMOS technology with wide
operating voltage for both tone and pulse mode, and consumes very low memory retention current in ON-HOOK
state. EM91810A/B also provide SDO (serial data output) function to drive LCD driver (EM32100, EM32116,
EM32117) and voice synthesizer.
FEATURES
Tone/pulse switchable dialer.
One 32-digit last number redial memory.
Pulse to tone (P
T) is provided for PBX operation.
Flash key is available.
Minimum tone duration is 98ms or 83ms.
Minimum intertone pause is 98ms or 83ms.
Uses 3.579545 MHz crystal or ceramic resonator.
Many options can be selected.
Mode (10 PPS ; 20 PPS ; Tone)
M/B ratio (40 : 60 ; 33 : 66)
Pause time (3.6s)
Flash function (RESET)
P
T pause time (3.6s)
Flash time (600ms; 300ms; 100ms; or 80ms).
Mixed dialing.
Handfree function is provided for speaker phone application.
Power on reset circuit is provided.
Package in DIP18 or DIP20.
SDO function that is supported to drive LCD driver (EM32100) and voice synthesizer to indicate dialing
number.
Key tone function is provided.
PIN ASSIGNMENTS
EM91810A/B
TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE
C2
C3
C4
C1
OSCI
OSCO
XMUTE
SDO
EM91810A
18
17
16
15
14
13
12
11
10
1
2
3
4
5
6
7
8
9
R3
R2
R1
R4
TONE
PO
HKS
V
KT
DD
SS
V
C2
C3
C4
C1
OSCI
OSCO
XMUTE
HFI
SDO
20
19
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
9
10
EM91810B
SS
V
DD
R3
R2
R1
R4
TONE
PO
HKS
V
HFO
KT
* This specification are subject to be changed without notice.
EM91810A/B
TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE
2
10.1.1997
KEYBOARD ASSIGNMENT
C1
C2
C3
C4
R1
1
2
3
P
T
R2
4
5
6
F
R3
7
8
9
P
R4
*or*/T
0
#
RD
1). P
T : In pulse mode, execute P
T function.
2). F
: Flash key.
3). RD
: Redial key.
4). P
: Pause key.
5). */T
: In pulse mode, execte P
T function
In tone mode, execte "*" key.
FUNCTIONAL BLOCK DIAGRAM
ROW2
OSC.
COLUMN
INTERFACE CKT.
DIVIDER
KERNEL CONTROL CKT.
ROW/COLUMN
PROGRAMMING
COUNTER
ROW
INTERFACE CKT.
LNB MEMORY
DECODER &
DATA LATCH
PULSE
GENERATOR
D/A CONVERTER
INPUT INTERFACE CKT.
OUTPUT INTERFACE CKT.
COL1
COL2
COL3
COL4
OSCI
OSCO
ROW1
ROW3
ROW4
HKS
HFI
V
SS
TONE
PO
XMUTE
HFO
V DD
SDO
KT
DIALING SIGNAL OPTION :
(820K
typically)
R
NR
R
R
NR
NR
NR
R
Row3 Row4 flash time(ms)
600
300
100
80
a]:Flash time:
Note: NR:no resistance.
R : A resistance connect to Vss
UR: A resistance connect to V
DD
MODE
PULSE RATE
M/B
R
NR
TONE
R
R
TONE
NR
NR
PULSE
20PPS
40:60
NR
R
PULSE
20PPS
33:66
UR
NR
PULSE
10PPS
40:60
UR
R
PULSE
10PPS
33:66
Row1 Row2
b).
c]:Tone function:
Tone Duration
inter-Tone
Pause
NR
R
98 ms
83 ms
98 ms
83 ms
Col1
*
R
*/T
NR
Col2
*or*/T
select
d]:Key type select
3
EM91810A/B
TONE/PULES SWITCHABLE DIALER WITH LCD INTERFACE
* This specification are subject to be changed without notice.
10.1.1997
PIN DESCRIPTION
Symbol
Function
C1
C2
C3
C4
R1
R2
R3
R4
OSCI
OSCO
XMUTE
V
SS
V
DD
HKS
PO
Figure 1a : Single contact form keyboard configuration
Row
Column
V
DD
VSS
VDD
VSS
Figure 1b : Dual contact form keyboard configuration
Figure 1c : Electronic signal input keyboard configuration
Row
Column
Row
Column
Provides keyboard scanning .
a. Keyboard scanning:
HKS pin is LOW, the column group stays in "HIGH" stays and row group stays in "LOW" state.
The key pad is compatible with the standard dual contact matrix keyboard (as Figure 1b.), the
inexpensive single contact keyboard (as Figure 1a.), and electronic input (as Figure 1c.).
When HKS is "low", a valid key entry is defined by related Row & Column connection or by
electronic input; (as show in Figure 1c).
Activation of two or more keys will result in no response, except for single key.
To avoid keyboard bouncing error, this chip provides built-in debounce circuit. (The debounce
time = 20 ms.)
Oscillator input & Oscillator output pins.
The 3.579545 MHz oscillator is formed by a built-in inverter inside of this chip and by connecting a
3.579545 MHz crystal or a ceramic resonator across the OSCI and OSCO pins. (built-in feedback
resistor and capacitor)
When HKS is "low", a valid key-in may turn on this oscillator and generates a 3.579545 MHz clock.
Mute output pins.
NMOS open drain output structure.
The output is in "low" state during dialing sequence (both Pulse and Tone mode) otherwise this pin
is "high-impedance" .
Long (continue) Mute.
Negative power supply pin.
Positive power supply pin.
Hook switch input pin.
When the handset is in ON-HOOK state, this pin must be pulled "high" in order to disable the dialing
operation and decrease the power consumption.
When in OFF-HOOK state, the HKS pin must be pulled "low" state for all function operation.
Pulse output signal pin.
NMOS open drain output structure.
The output is "low" during pulse dialing and Flash operation, otherwise this output is "floating".
* This specification are subject to be changed without notice.
EM91810A/B
TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE
4
10.1.1997
Symbol
Function
TONE
HFI
HFO
SDO
KT
Dual Tone Multi-frequency output pin.
In TONE mode, when a entry of digit key (include * , # key), this pin will sent out a corresponding
DTMF signal.
The TONE pin provides minimum tone duration (t
TD
),& minimum intertone pause time to support rapid
key-in. If key-in time is less than t
TD
, DTMF signal will last for t
TD
, otherwise the tone duration will
last as long as the key is pressed.
Handfree input control pin.
Toggle input sturcture, falling edge trigger.
It is used to enable and disable Handfree function.
With waveshaped by a built-in Schmit trigger, the bounce of input can be eliminated by external R,
C debounce circuit.
A built-in pull up resistor is 200K typical.
Handfree output pin.
Inverter output structure (normally "low", active "high").
When a HFI pin is active, Handfree function will be enabled (HFO=1) or disabled (HFO=0).
When the Handfree function is enable (HFO=1), after OFF-HOOK action, it can reset Handfree
function and HFO pin return to "low" state.
Serial data output pin.
NMOS open drain output structure.
When there is a valid entry 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.
Key tone output pin for key pad input. The key tone duration is the same as the key pressed time.
No matter at Tone mode or pulse mode.
Inverter output structure.
FUNCTION DESCRIPTION
Keyboard Operation
Symbol definitions:
a).
: OFF-HOOK or enable Hand Free function.
b).
: ON-HOOK or disable Hand Free function.
c).
: Input level from low to high.
d).
: Input level from high to low.
e). D
1
.....D
n
: Digit key; 1,2,3,4,5,6,7,8,9,0,*,# (C
1
.....C
n
is same as D
1
.....D
n
).
f). D
P1
... D
Pn
: Pulse digit ; 1,2,3,4,5,6,7,8,9,0, (C
P1
... C
Pn
is same as D
P1
... D
Pn
).
g). D
t1
....D
tn
: Tone digit ; 1,2,3,4,5,6,7,8,9,0,*, # (C
t1
....C
tn
is same as D
t1
....D
tn
).
h). t
F
: Flash time.
i). t
P
: Pause time.
j). t
PT
: Pulse to Tone wait time.
k). t
FP
: Pause time for flash.
l). t
RP
: Pause time for redial.
m). LNB
: Last number redial buffer.
5
EM91810A/B
TONE/PULES SWITCHABLE DIALER WITH LCD INTERFACE
* This specification are subject to be changed without notice.
10.1.1997
A. Normal Dialing
1. Digit Dialing
Procedure :
D1,D2 . . . . . ., Dn
Dial out
: Dt1, Dt2 . . . . . . ., Dtn in tone mode
Dial out
: Dp1, Dp2 . . . . . ., Dpn in pulse mode
LNB
: D1, D2 . . . . . . Dn
2. Dialing with flash key
Procedure :
F,D1,D2 . . . . . ., Dn
Dial out
: t
F
, Dt1,Dt1 . . . . . . ., Dtn in tone mode
Dial out
: t
F
,Dp1,Dp1 . . . . . . ., Dpn in pulse mode
LNB
: D1, D2 . . . . . . . Dn
3. Dialing with P
T key
Procedure :
D1, D2 . . . . . .,P
T, . . . . . , Dn
Dial out
: Dp1, Dp2, . . . . t
PT
, . . . . . , Dtn in pulse mode
LNB
: D1, D2 . . . . . ,P
T, . . . . Dn
Note : If key in digit over maximum digit stored in LNB, then RD is inhibited even after on/off hook.
B. Mixed dialing
Procedure :
D1, D2 . . . . . .,P
T, D9,D10, . . . . . , Dn
Dial out
: Dp1, Dp2, . . . . t
PT
, Dt9,Dt10 . . . . . , Dtn
LNB
: D1, D2 . . . . . ,P
T, D9,D10 . . . . Dn
C. Redial
LNB
: D1, D2 . . . . . Dn
Procedure :
RD
Dial out
: Dt1, Dt2, . . . . Dtn in tone mode
Dial out
: Dp1, Dp2, . . . . Dpn in pulse mode
Note : If key in digit over maximum digit stored in LNB, then RD is inhibited.
D. Pause Function
Procedure :
D1, D2, . . . .Dn, P, C1 . . . . .Cn
Dial out
: Dt1, Dt2, . . . . Dtn , tp, Ct1 . . . . . . . . . Ctn in tone mode
Dial out
: Dp1, Dp2, . . . . Dpn,tp, Cp1 . . . . . . . . .Cpn in pulse mode
LNB
: D1, D2 . . . . . Dn, P, C1, C2 . . . . . . . . . .Cn
E. Flash Function
1. Reset
Procedure :
D1, D2, . . . .Dn, F, C1 . . . . .Cn
Dial out
: Dt1, Dt2, . . . . Dtn , t
F
,Ct1 . . . . . . . . . Ctn in tone mode
Dial out
: Dp1, Dp2, . . . . Dpn, t
F
,Cp1 . . . . . . . . .Cpn in pulse mode
LNB
: C1, C2 . . . . . Cn
PDF 
ZIP