Silan
Semiconductors SC91710A/B
TONE / PULSE SWITCHABLE DIALER
WITH HANDFREE FUNCTION
DESCRIPTION
The SC91710A/B are Tone/Pulse switchable dialer which are
fabricated in COMS technology with wide operating voltage for both
DIP-16
tone and pulse mode, and consumes very low memory retention
current in ON-HOOK state.
FEATURES
*Tone/Pulse switchable dialer
*One 32-digit last number redial memory
*Pulse-to-tone (P→T) is provided for PBX operation
DIP-18
*Flash key is available
*Minimum tone duration is 98ms or 83ms
*Minimum intertone pause is 98ms or 83ms
*Redial Pause time (0ms)
*Mixed dialing
*Uses 3.579549MHz crystal or ceramic resonator
*Power on reset circuit is provided
*Many options can be selected
*Handfree function is provided for speaker
Mode (10PPS; 20PPS; Tone)
phone application
M/B ratio (40:60;33:66)
*Packaged in 16-DIP or 18-DIP
Pause time (3.6s)
*Flash function (RESET)
ORDERING INFORMATION
(P→T) pause time (3.6s)
SC91710A
SC91710B
Flash time (600ms; 300ms; 100ms; or 80ms)
DIP-16 Packaged
DIP-18 Packaged
PIN CONFIGURATION
16
R3
C3
2
15
R2
C4
3
14
R1
C1
4
OSCI
5
OSCO
13
C2
1
18
R3
C3
2
17
R2
C4
3
16
R1
15
R4
14
TONE
13
PO
C1
4
OSCI
5
OSCO
6
XMUTE
7
12
HKS
VSS
8
11
VDD
HFI
9
10
HFO
R4
12
TONE
6
11
PO
XMUTE
7
10
HKS
VSS
8
9
VDD
SC91710B
1
SC91710A
C2
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
1
2001-11-13
Silan
Semiconductors SC91710A/B
COLUMN
INTERFACE CKT.
COL3
COL4
PULSE
GENERATOR
OSCI
OSC.
DIVIDER
ROW
INTERFACE CKT.
OSCO
ROW1
ROW2
ROW3
PO
DECODER &
DATA LATCH
LNB MEMORY
ROW/COLUMN
PROGRAMMING
COUNTER
D/A CONVERTER
TONE
INPUT INTERFACE CKT.
HFI
HKS
ROW4
VDD
INPUT INTERFACE CKT.
KERNEL CONTROL CKT.
COL2
VSS
COL1
HFO
XMUTE
BLOCK DIAGRAM
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) P: Pause key.
3) F: Flash key
4) RD: Redial key
5) In pulse mode, execute P→T function.
In tone mode, execte “*” key
DIALING SIGNAL OPTION
A: Flash time
B:
MODE
PULSE RATE
M/B
Row3
Row4
Flash time(ms)
Row1
Row2
NR
NR
600
R
NR
TONE
--
--
NR
R
300
R
R
TONE
--
--
R
NR
100
NR
NR
PULSE
20PPS
40:60
R
R
80
NR
R
PULSE
20PPS
33:66
UR
NR
PULSE
10PPS
40:60
UR
R
PULSE
10PPS
33:66
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
2
2001-11-13
Silan
Semiconductors SC91710A/B
C: Tone function
Tone Duration
Col1
D: Key type select
Inter-Tone Pause
Col2
*or */T select
NR
98ms
98ms
NR
*
R
83ms
83ms
R
*/T
Note:
NR: no resistance
R:
A resistance connect to VSS (820kΩ typically)
UR: A resistance connect to VDD
ABSOLUTE MAXIMUM RATINGS
(Tamb=25°C, All voltage referenced to VSS, unless otherwise specified)
Characteristic
Symbol
Value
Unit
Power Supply Voltage
VDD
6.0
V
Input Voltage
VIN
-0.3~VDD+0.3
V
Power Dissipation
PD
500
mW
Operating Temperature
Topr
-25~+70
°C
Storage Temperature
Tstg
-55~+150
°C
ELECTRICAL CHARACTERISTICS
(Tamb=25°C, VDD=2.5V, fosc=3.579545MHz, unless otherwise specified)
Parameter
Symbol
Conditions
Min
Typ
Max
Tone
2.5
--
5.5
Pulse
2.0
--
5.5
Memory retention
1.0
Unit
DC Characteristics
Operating Voltage
VDD
Operating Current
IOP
V
5.5
Tone
OFF-HOOK,
--
0.6
2
Pulse
Keypad entry
--
0.2
0.5
mA
ON-HOOKNo keypad entry
--
0.1
1
µA
Memory Retention Current
Imr
ON-HOOKVDD=1.0V
--
0.1
0.2
µA
Control Pin Input Low Voltage
Vil
--
VSS
0.3VDD
Control Pin Input High Voltage
Vih
--
0.7VDD
VDD
XMUTE Pin Leakage Current
Imth
V XMUTE =6.0V
--
--
1
µA
XMUTE Pin Sink Current
Imtl
V XMUTE =0.5V
0.2
0.5
--
mA
µA
Standby Current
IS
HKS Pin Input Current
Ihks
Vhks=2.5V
--
--
0.1
Keyboard
Drive Current
Ikbd
Vn=0Vnote1
4
10
30
Scanning Pin
Sink Current
Ikbs
Vn=2.5note1
200
400
800
tDB
--
--
20
Key-in Debounce Time
V
µA
--
ms
(to be continued)
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
3
2001-11-13
Silan
Semiconductors SC91710A/B
(continued)
Parameter
Symbol
HFI pin input resistor
Rhfi
HFO pin drive current
Ihdoh
HFO pin sink current
Ihdol
Conditions
Min
Typ
Max
--
200
--
kΩ
Vhfo=2.0V
0.5
--
--
mA
Vhfo=2.5V
0.5
--
--
mA
VDD=2.5
Unit
Pulse Mode
Pulse Output Pin Leakage Current
Ipoh
Vpo=2.5V
0.1
--
--
µA
Pulse Output Pin Sink Current
Ipol
Vpo=0.5V
0.5
--
--
mA
Pulse Rate
fpr
--
10
--
--
20
--
--
40:60
--
--
33:66
--
M/B ratio=40:60
--
40
--
M/B ratio=33:66
--
33
--
Pulse rate=10pps
--
800
--
Pulse rate=20pps
--
500
--
Make/Break Ratio
tMtB
Pre-digit Pause
tPDP
Inter-digit Pause
tIDP
pps
%
ms
ms
Tone Mode
DC Level
Tone
Sink Current
Output Pin
AC level
Vdc
Itl
Vdtmf
Load Resistor
DTMF Signal
RI
Pre-emphasis
twist
Distortion(note 2)
0.5VDD
--
0.7VDD
V
Vdtmf=0.5V
VDD=2.0V~5.5V
0.2
--
--
mA
Row groupRL=10KΩ
130
155
170
mVrms
Dist.≤ -23dB
10
--
--
KΩ
1
2
3
dB
VDD=2.0~5.5 V,
Column-Row group
Dist.
RL=10KΩ
--
-30
-23
dB
Minimum tone duration Time
tTD
Auto redial
--
98/83
--
ms
Minimum Intertone Pause Time
tITP
Auto redial
--
98/83
--
ms
Note: 1. Vn: Input voltage of any keyboard scanning pin (Row group, Column group)
2Distortion (dB) = 20log{[V12+V22+V32+…Vn2)1/2]/[(VL2+VH2)1/2]}
VL,VH: Row group and Column group signal , V1V2…Vn: Harmonic signal (BW = 300Hz~3500Hz
ACTUAL FREQUENCY OUTPUT (fosc=3.579545MHz)
Keyboard Scanning Pin
Standard(Hz)
Output
Deviation(%)
R1
f1
697
699
+0.28
R2
f2
770
766
-0.52
R3
f3
852
848
-0.47
R4
f4
941
948
+0.74
C1
f5
1209
1216
+0.57
C2
f6
1336
1332
-0.30
C3
f7
1477
1472
-0.34
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
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2001-11-13
Silan
Semiconductors SC91710A/B
PIN DESCRIPTION
Pin No.
SC91710A SC91710B
4
4
Pin Name
C1
Description
*Provides keyboard scanning.
* HKS pin is LOW, the column group stays in “HIGH” state and row group
stays in “LOW” state.
*The keypad is compatible with the standard dual contact matrix keyboard
1
1
C2
(as figure1b), 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 &
2
2
C3
Column connection or by electronic input (as shown in figure 1c).
*Activation of two or more keys will result in no response, except for single
key.
3
14
3
16
C4
R1
*To avoid keyboard-bouncing error, this chip provides built-in debounce
circuit. (The debounce time = 20ms)
Row
Column
Row
Column
15
17
R2
Figure1a: Single contact form
keyboard configuration
Row
Figure1b: Dual contact form
keyboard configuration
VDD
VSS
16
18
R3
Column
VDD
VSS
13
15
R4
5
5
OSCI
Figure1c: Electronic signal input keyboard configuration
*Oscillator input & output pins.
*The 3.579545MHz oscillator is formed by a built-in inverter inside of this
chip and by connecting a 3.579545MHz crystal or a ceramic resonator
across the OSCI and OSCO pins. (built-in feedback resistor and capacitor)
6
6
OSCO
*When HKS is “LOW”, a valid key-in may turn on this oscillator and
generates a 3.579545 MHz clock.
(to be continued)
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
5
2001-11-13
Silan
Semiconductors SC91710A/B
( continued )
Pin No.
Pin Name
SC91710
SC91710B
A
Description
*Mute output pins.
*NMOS open drain output structure.
7
7
XMUTE
*The output is in “LOW” state during dialing sequence (both Pulse and
Tone
mode) otherwise this pin is “high-impedance”.
*Long (continue) Mute.
8
8
VSS
*Negative power supply pin.
9
11
VDD
*Positive power supply pin.
*Hook switch input pin.
*When the handset is in ON-HOOK state, this pin must be pulled “high” in
10
12
HKS
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.
11
13
PO
*NMOS open drain output structure.
*The output is “LOW” during pulse dialing and Flash operation, otherwise
this output is “floating”.
*Dual Tone Multi-frequency output pin.
*In TONE mode, when an entry of digit key (include *, # key), this pin will
send out a corresponding DTMF signal.
12
14
TONE
*The TONE pin provides minimum tone duration and minimum intertone
pause time to support rapid key-in. If key-in time is less than 100ms,
DTMF signal will last for 100ms; otherwise the tone duration will last as
long as the key is pressed.
* Handfree input control pin.
* Toggle input structure, falling edge trigger.
9
HFI
* 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 down resistor is 200k typical.
* Handfree output control pin.
* Inverter output structure (normally ‘low’, active ‘high’).
10
HFO
* When a HFI pin is active, Handfree function will be enabled (HFO=1) or
disable (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.
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
6
2001-11-13
Silan
Semiconductors SC91710A/B
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)
D1~Dn
:
Digit key1, 2, 3, 4, 5, 6, 7, 8, 9, 0, *, #, (C1~Cn is same as D1~Dn).
f)
Dp1~Dpn
:
Pulse digit1, 2, 3, 4, 5, 6, 7, 8, 9, 0, (Cp1~Cpn is same as Dp1~Dpn).
g)
Dt1~Dtn
:
Tone digit1, 2, 3, 4, 5, 6, 7, 8, 9, 0, *, #, (Ct1~Ctn is same as Dt1~Dtn).
h)
tF
:
Flash time.
i)
tP
:
Pause time.
j)
tPT
:
Pulse to Tone wait time.
k)
tFP
:
Pause time for flash.
l)
tRP
:
Pause time for redial.
m)
LNB
:
Last number redial buffer.
ANormal Dialing
1. Digit Dialing
Procedure
↑
Dial out
Dt1,
Dt2…,
Dial out
Dp1,
Dp2,…, Dpn (in Pulse mode)
LNB
D1,
D2…,
D1,
D2…, Dn↓
Dtn (in Tone mode)
Dn
2. Dialing with flash key
Procedure
↑
Dial out
t F,
tFP,
Dt1,
Dt2…,
Dial out
t F,
tFP,
Dp1,
Dp2,
LNB
D1,
F, D1, D2…, Dn
D2…,
↓
Dtn (in Tone mode)
…,
Dpn (in Pulse mode)
Dn
3. Dialing with P→T key
Procedure
↑
Dial out
Dp1,
LNB
D1,
D1,
D2
…,
Dp2, …,
D2 …,
P→T , …,
Dn
↓
tPT, …, Dpn (in Pulse mode)
P→T , …,
Dn
Note: If key in digit over maximum digit stored in LNB, then RD is inhibit even after on/off hook.
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
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Silan
Semiconductors SC91710A/B
BMixed dialing
Procedure
↑D1,
D2…,
Dial out
Dp1,
Dp2, …,
LNB
D1,
LNB
D1,
Procedure
↑
Dial out
tRP,
Dt1,
Dt2…,
Dial out
tRP,
Dp1,
Dp2,…,
P→T ,
tPT,
D2…, P→T ,
D9,
Dt9,
D10 …,
Dt10…,
Dn↓
Dtn
D9,
D10 …,
Dn
Dtn
(in Tone mode)
CRedial
D2…,
Dn
↓
RD
Dpn
(in Pulse mode)
Note: If key in digit over maximum digit stored in LNB, then RD is inhibit.
DPause Function
Procedure
↑
Dial out
Dt1,
Dt2 ,…,
Dial out
Dp1,
Dp2, … Dpn , tP, Cp1 …,
LNB
D1, D2…, Dn, P , C1, C2 …, Cn
D1,
D2…,
Dn, P, C1 …,
Dtn, tP, Ct1,
↓
Cn
Ctn
(in Tone mode)
Cpn
(in Pulse mode)
EFlash Function
1. Reset
Procedure
↑
Dial out
Dt1,
Dial out
Dp1,
LNB
C1,
D1,
D2…,
Dn,
F,
Dt2,…, Dtn , t F,
Dp2,…, Dpn ,
C2 …,
C1 …, Cn
tFP,
t F,
↓
Ct1 …, Ctn
(in Tone mode)
tFP, Cp1 …, Cpn
(in Pulse mode)
Cn
Handfree Function operation:
A) To execute Handfree function: When HFO = ’low’, HFI pin is active, the Handfree function will be enabled (HFO
= ’high’)
B) Reset Handfree function:
a. OFF-HOOK action.
b. When HFO = ’high’, a HFI pin is active again, the Handfree function will be reset (HFO=’low’).
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
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Silan
Semiconductors SC91710A/B
Operating flow chart of Handfree
ON HKS
(0)
INITIAL
OFF
HF
HF
ON HKS
(1)
HF LINE
ON
OFF HKS
(2)
LINE
OFF
HF
ON
HF
OFF HKS
(3)
HF LINE
Note:
STATE NO.
ON: ON HKS; OFF: OFF HKS; HF: Pressed HF key
PO
XMUTE
HFO
(0) INITIAL STATE
F
F
0
(1) ON HKS HF LINE
F
F
1
(2) OFF HKS LINE
F
F
0
(3) OFF HKS HF LINE
F
F
1
* F: Floating
(Hi-impedance)
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
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2001-11-13
Silan
Semiconductors SC91710A/B
TEST CIRCUIT
1
Operation
current
V+
Standby
current
2
A
DP
DP
DT
VDD
keyboard
MODE
HKS
VSS
V+
A
VDD
VSS
3 Tone output voltage
4
Tone distortion
V+
V+
counter
and
AC meter
VDD
keyboard
HKS
TONE
VSS
10KΩ
6
Pulse output sink current
(open drain structure)
HKS
V
10KΩ
Pulse output sink current
(inverter structure)
V+
V+
VDD
Flash
key
Spectrum
analyzer
VDD
keyboard
TONE
VSS
5
HKS
VSS
HKS
VDD
A
PO
V
VEXT
HKS
PO
VSS
7 Keypad input current (row group)
VDD
V
VEXT
8 keypad input current (column group)
V+
A
A
V+
VDD
R*
R*
COLUMN
ROW
C*
A
HKS VSS MODE
C*
HKS VSS MODE
Note: 1. Dist. (dB)=20log{[V12+V22+V32+…Vn2)1/2]/[(VL2+VH2)1/2]}
a. V1…Vn are extraneous frequencies (ie, inter modulation and harmonic), components in the 500Hz
to
3400Hz band.
b. VL,VH
are the individual frequency components of DTMF signal.
c. Whether keyboard is pushed refer to the TONE mode time diagram.
2. Sink current Isink=I/(1-Duty Cycle), I is the net DC current measured from ampere meter.
3. R*, C* mean other column and row.
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
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Semiconductors SC91710A/B
TIMING DIAGRAMS
HKS
3
2
3
KEY IN
tDB
XMUTE
PO
TONE
tTD
tITP
tITP
tITP
OSCO
......High impedance
Normal dialing
Tone Mode Timming Diagram
HKS
3
2
3
KEY IN
tDB
XMUTE
tPDP
PO
TONE
tM
tB
tTD
tIDP
tIDP
tIDP
OSCO
Normal dialing
......High impedance
Pusle Mode Timming Diagram
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
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Semiconductors SC91710A/B
TIMING DIAGRAMS (continued)
HKS
3
2
3
P→T
KEY IN
tDB
XMUTE
tPDP
PO
TONE
tIDP
tPT
tIDP
tITP
OSCO
......High impedance
Timming Waveform for mixed dialing Operation
(by P→T key entry)
HKS
KEY IN
F
tDB
XMUTE
PO
TONE
tF
OSCO
......High impedance
Flash key operating timming
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
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Semiconductors SC91710A/B
TIMING DIAGRAMS(continued)
HKS
3
2
RD
KEY IN
tDB
XMUTE
PO
tITP
tITP
tITP
tITP
TONE
tD
OSCO
......High impedance
Tone Mode Redial Timming Diagram
HKS
3
2
RD
KEY IN
tDB
XMUTE
tRP
tIDP
tIDP
PO
tIDP
tIDP
TONE
OSCO
......High impedance
Pulse Mode Redial Timming Diagram
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
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2001-11-13
Silan
Semiconductors SC91710A/B
TIMING DIAGRAMS(continued)
HKS
KEY IN
*PULSE MODE
XMUTE
3
2
P
3
tDB
tPDP
tIDP
tIDP
tP
tIDP
PO
TONE
OSCO
*TONE MODE
tDB
XMUTE
PO
tITP
tITP
tP
tITP
TONE
OSCO
......High impendance
Pause key operating timming
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
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2001-11-13
SC91710A/B
TYPACAL APPLICATION CIRCUIT
ON/OFF
HOOK
22MΩ 100kΩ
P→T
15 R2
14 R1
1N4004x4
MPSA92
3
F
16 R3
1N4148
330kΩ
11
PO
1µF
1
4
9
VDD
5.1V
470kΩ
SC91710A
6
2kΩ
10
HKS
C945
1µF
TONE 12
XMUTE 7
8
OSCO VSS
3.579545MHz
5
OSCI
100µF
16V
240kΩ
2.2kΩ
2
6
P
2
1N4148x2
100µF
16V
Tip
ZNR
120V
1
5
9
13 R4
Ring
4
8
R/P
3
VDD
100kΩ
2 wrie to 4 wire
Speech network
TO HANDSET
15
MPSA42
7
#
100kΩ
C4 C3 C2 C1
0
820kΩx5
*
TONE
20pps
10pps
Silan
Semiconductors 2001-11-13
Rev: 2.0
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
SC91710A/B
TYPACAL APPLICATION CIRCUIT
4
1
8
5
2
#
9
6
3
R/P
P
F
P→T
1N4004x4
ZNR
120V
MPSA92
C954
100kΩ
330kΩ
3
13
47kΩ
2
1
200kΩ
C945
4
1N4148
5.1V
470kΩ
12
HKS
5
OSCI
SC91710B
1µF
100µF
16V
6
11
2.7kΩ
14
1µF
0.2µF
HFO 10
VDD TONE
9
XMUTE 7
8
HFI
OSCO VSS
3.579545MHz
C954
200kΩ
2 wrie to 4 wire
Speech network
& Audio amplifier
TO HANDSET
HF
KEY
2001-11-13
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
22MΩ
100kΩ
HOOK ON/OFF
240kΩ
3.3kΩ
13 R4
16 R3
15 R2
14 R1 PO
47kΩ
Tip
7
0
1µF
C4 C3 C2 C1
VDD
16
Ring
*
820kΩx6
TONE
20pps
10pps
Silan
Semiconductors Silan
Semiconductors SC91710A/B
CHIP TOPOGRAPHY
Size: 1.45 x 1.54 mm
2
PAD COORDINATES (Unit: µm)
No.
Symbol
X
Y
No.
Symbol
X
Y
1
P1
-542.6
-238.0
10
P10
562.4
88.5
2
P2
-542.6
-468.1
11
P11
562.4
252.4
3
P3
-542.6
-602.5
12
P12
562.4
445.8
4
P4
-315.0
-602.5
13
P13
562.4
603.8
5
P5
-134.8
-602.5
14
P14
P6
85.5
-602.5
15
P15
148.6
-22.4
603.8
6
7
P7
562.4
-439.1
16
P16
-251.0
8
P8
562.4
-277.6
17
P17
-542.6
124.7
9
P9
562.4
-93.6
18
P18
-542.6
-102.9
603.8
603.8
Note: The original point of the coordinate is the die center.
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
17
2001-11-13
Silan
Semiconductors SC91710A/B
PACKAGE OUTLINE
DIP-16-300-2.54
UNIT: mm
7.62
6.40
0.25
2.54
1.50
15 degree
3.30
5.08
3.51
19.4
0.46
DIP-18-300-2.54
UNIT: mm
6.40
7.62
0.25
2.54
1.50
15 degree
3.30
5.08
3.51
22.95
0.46
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.0
18
2001-11-13