Datasheet SC83702 Datasheet (SILAN)

Silan
Semiconductors





ALL IN ONE MOUSE CONTROLLER

DESCRIPTION

The SC83702 Mouse Controller is specially designed to control
mouse device. This single chip can interface three key-switches and
four photo-couple direct to RS-232C. The SC83702 does not need
any external power supply, so the mouse can go without a power
line. It is versatile with both microsoft and mouse system.
Debouncing circuit were provided to prevent false entry and to
improve the accuracy. In 1200 baud rate non-auto speed with 200
DPI wheels and photo-couples, the scanning is 650mm/sec without
missing a dot in microsoft mode, and the scanning speed can up to
770mm/sec in mouse system mode.

SC83702

SOP-16

DIP-16

FEATURES

*Built-in two zener diode between VDD and VSS, RTS and VDD

*Built-in noise immunity circuit

*CMOS DIP 16 pins package&SOP 16 pins package

*Low power dissipation

*Use 32.768KHz crystal or 3.58MHz resonator

*Oscillator circuits on-chip

*Serial output in 1200 baud rate

*Can be powered directly from RS-232C

*Can drive directly to RS-232C

*Three key-switches and four photo-couples inputs

*Both key-in and key-release debounce interval 13ms

PIN CONFIGURATIONS

RS

MS

OSCI

OSCO

RTS

RXD

VSS

R

1
2
3
4

SC83702A

5
6
7
8

16
15
14
13
12
11
10

VDD

OPT

Y2

Y1

X2

X1

L

M

9

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

1

*Through three key-switches input,

SC83702 can exert seven different output

*The sampling rate of motion detector is

65KHz

APPLICATIONS

*Optical mouse or pen-mouse
*Mechanical mouse or pen-mouse
*Optomechanical mouse or pen-mouse
*Mechanical track ball
*Optomechanical track ball

RS

OPT

MS

OSCI

OSCO

RTS

RXD

VSS

1
2
3
4

SC83702B

5
6
7
8

16
15
14
13
12
11
10

VDD

Y2

Y1

X2

X1

L

M

R

9

Rev: 1.0 2000.12.31







Silan
Semiconductors



BLOCK DIAGRAM

OPT

2

X1

12

X2

13

Y1

14

Y2

15

L

11

M

10

R

9

MS

3

RS

1

OSCO

5

OSCI

14

MOTION

DETECTOR

DEBOUNCE

SYSTEM

CLOCK

GENERATOR



NOISE

IMMUNITY

VDD Vss

16 8

SELECTOR

MODE

MULTI-

PLEXER

CONTROLLER

LEVEL

SHIFT

CIRCUIT

SC83702

P/S

TIMING

RXD

7

RTS

6

NOTE: The pin numbers refer to SC83702B.

ABSOLUTE MAXIMUM RATINGS

Characteristic Value Unit

Supply Voltage

Temperature Under Bias 0~70

Storage Temperature -65~+150

Power Dissipation 600 mW

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

(Tamb=25°C, unless otherwise specified)

V

Vss -0.3~+7.0 V

DD-

RTS-Vss -0.3~+14 V

Rev: 1.0 2000.12.31

2

°C
°C





Silan
Semiconductors





DC ELECTRICAL CHARACTERISTICS

Parameter Symbol Min Typ Max Unit

Operating Voltage

Operating Current (VDD=5.4V, RTS=VDD, 32.768kHz, No Load) Iop -- -- 0.6 mA
Operating Current (VDD=6.2V, RTS=VDD, 32.768kHz, No Load) Iop 3 -- -- mA
Operating Current (VDD=5.4V, RTS=VDD, 3.58MHz, No Load) Iop -- -- 1.6 mA
Operating Current (VDD=6.2V, RTS=VDD, 3.58MHz, No Load) Iop 4 -- -- mA
RTS Operating Current (VDD=5.6V, RTS=11V) I
RTS Operating Current (VDD=5.6V, RTS=11.8V) I
RXD High Output Current (Vrh=Vrts-2.6V) Irh 2.0 -- -- mA
RXD Low Output Current (Vrl=Vss+2.6V) Irl -- -- -2.0 mA
X1,X2,Y1,Y2 Low Input Voltage Vpl -- -- 0.7 V
X1,X2,Y1,Y2 High Input Voltage Vph 1.3 -- -- V
X1,X2,Y1,Y2 Input Current (Pull Low Resistor, Vds=1.0V) Ipi 57 -- 104
RTS High Input Voltage Vth 9.6 -- -- V
RTS Low Input Voltage Vtl -- -- 6.8 V
Low Input Voltage, Other Pins Vail -- -- 1.5 V
High Input Voltage, Other Pins Vaih 3.5 -- -- V
L,M,R,OPT Input Current (Pull LowResistor, Vds=5.6V) Imi 18.6 -- 56
Rs,Osc-In,L,M,R,X1,X2,Y2,Y2,Opt
Input Leakage Current (Vin=0V)
RS, OSC-IN Input Leakage Current (Vin=5.6V) Iih -1.0 -- 0

NOTE: *All voltages in above table are compared with VSS.

*All parameters in above table are tested under V

AC ELECTRICAL CHARACTERISTICS

Parameter Symbol Min Typ Max Unit

Key debounce Tkd -- 13 -- ms

Transmission time mouse(1200) Tms -- 41.1 -- ms

Transmission time microsoft(1200) Tmx -- 24.7 -- ms

Start bit time (1200) Ts -- 0.85 -- ms
Data bit time (1200) Td -- 0.82 -- ms
Stop bit time (1200) Tp -- 0.82 -- ms

Mode code delay time (1200) Trd 11.9 -- 14 ms
Rising edge crossed width Tr 15 -- -­Falling edge crossed width Tf 15 -- --

(Tamb=25~70°C, VDD=5.6V)

V

DD

V

RTS

RTS
RTS

Iil 0 -- 1.0

=5.6V

DD

(Tamb=25~70°C)

-- -- 6.5 V

-- -- 13 V

-- -- 0.6 mA
3----mA

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

3

SC83702

µA

µA

µA

µA

µs
µs

Rev: 1.0 2000.12.31





Silan
Semiconductors



AC TIMING TEST POINT

OUTPUT: RXD pin



V

RTS

-2.4V

SC83702

Vss+0.8V

INPUT:X1,X2,Y1,Y2 pins

RTS pin

Other pins

X1,X2,Y1,Y2 INPUT IMPEDANCE

UNIT:KΩ

MAX.

17.0

16.0

15.0
TYP.

14.0

13.0

12.0

MIN.

11.0

10.0

9.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0
0 1.0 2.0 3.0 4.0 5.0

INPUT VOLTAGE

PIN DESCRIPTION

Pin Name I/O Description

RS I

RXD O

Crystal type select: "0" or floating. select 32.768KHz crystal. "1" select 3.58MHz
resonator.
There are 8 or 7 bits in each data byte.
Using parallel-in and serial-out components, the databytes are shifted out from bit 0
through the high bits. SC83702 will transmit the data while the status of three key
switches or the state of the horizontal counter or vertical counter is changed.

2V

1.3V

0.7V

Vss

V

Vss

DD

DD

(to be continued)

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

4





Silan
Semiconductors



(continued)

Pin Name I/O Description

MS I

OSC.IN I

OSC.OUT O

RTS I

V

SS

RI

M I/O

L I/O

X1

X2

Y1

Y2

OPT I Whenever OPT is connected to VDD, the chip will enter testing mode.

V

DD

-- Negative power input.

I

-- Power



When this pin is connected to V
microsoft mode only. If the pin is connected to Vss, then SC83702 will operate
under the mouse system mode.
However if this pin is "floating", then SC83702 is on the "power on initiation"
situation and if any one of three buttons is chosen, then SC83702 will operate under
the mouse mode. And while the whole system is on "power on initiation", no key is
chosen then operation will be under microsoft mode.
A built-in inverter provides oscillation with 32.768KHz crystal or 3.58MHz resonator.
Several counters used to decrease the frequency of oscillation and create 1200
baud rate, key-switches debounce and photo-couple sensor scanning clock, etc.
Positive power input. The signal is sent by mouse driver from computer to the
mouse to select a mode. During the reset time, SC83702 echoes the selected mode
to the RXD line after the reset pulse signal of the RTS line. RXD will send out CD
(H) code if it is under the microsoft mode. RXD will send out two-byte C8 (H) code if
it is under the mouse system mode in SC83702.

Three key-switches exert seven different combinations totally.
Both key-pressed and key-released signals will besent accompanied with horizontal
and vertical state. The status of the key-switches will be preserved, whenever the
value of horizontal or vertical counters will present at RXD. And the debounce
interval for both key-press and key-release is 13ms.
In testing mode, L and M are the outputs of motion detector. Using R key can select
the two outputs X1, X2 or Y1, Y2. This feature can help manufacturer to adjust the
phase of four photo-couples for improving the yield.
Four photo-couple signals denote UP, DOWN, LEFT and RIGHT state. If SC83702
is in 1200 baud rate on non-auto speed mode, the system provides 40 transmission
cycles per second in microsoft mode to the utmost. In mouse system mode, the
cycles are 24 maximum. During the scanning period, as long as the photo couples
change their states, the value of vertical or horizontal counter will increase or
decrease accordingly.

, then SC83702 is assigned to operate under the

DD

SC83702

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

5





Silan
Semiconductors





FUNCTION DESCRIPTIONS

1.OPERATING MODE

A) Mouse System Mode

Anytime the mouse changes its state, includingthe key-switches and the photo-couple sensors, SC83702 will
detect the result and transmit to RS-232C. Mouse system transmits the result w ith five bytes in 1200 baud rate.
Each byte contains 10 bits, one start bit, one stop bit and eight data bits. The first byte represents the key­switches status. The second byte denotes the number counted by the horizontal counter. The third byte conveys
the number accumulated by the vertical counter. If the mouse is moved faster, the photo-couple sensors detect
the "change state" and output the record, excessive horizontal counter will be transported through the fourth byte
and vertical counter through the fifth byte. Otherwise, the fourth and fifth byte are zero. Output bytes arrange:

Bit No. 76543210
1st Byte 10000L’*M’*R’*
2nd Byte H7 H6 H5 H4 H3 H2 H1 H0

3rd

Byte V7 V6 V5 V4 V3 V2 V1 V0
4th Byte H7 H6 H5 H4 H3 H2 H1 H0
5th Byte V7 V6 V5 V4 V3 V2 V1 V0

*

: “ ’ ” denotes complement

B) Microsoft Mode

In microsoft mode, the transmission cycle consists of three bytes. Each byte is divided into one start bit, seven

data bits and two stop bits. The first byte contains "L", "R" switch status and four bits of the two most significant
bits in horizontal counter and vertical counter. The next byte represents the value accumulated by horizontal
counter, the last byte is the data of the vertical counter. Notice that "M" key-switch is not active in the microsoft
mode and the vertical data is transmitted in 2's complement.

Bit No.

1st Byte 1LRV7'V6'H7H6

2nd Byte 0 H5H4H3H2H1H0

3rd Byte 0 V5' V4' V3' V2' V1' V0'

2.TESTING MODE

Whenever OPT is connected to VDD, the chip will enter buyer's testing mode. The X direction output signal

generators will present to L and M pin. Pressing "R" key can toggle the output from X direction to "Y" direction.

6543210

SC83702

3.ECHO MODE

RXD will send out CD (H) code when RTS rise from low to high under microsoft mode. Under mouse system

mode, when RTS rise from low to high, the RXD pin SC83702 willsend out two byte C8 (H) code.

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

6





Silan
Semiconductors



TIMING DIAGRAM

(A) P/S Output



Key in/release

SC83702

Mouse RXD

Microsoft RXD

(B) Bytes Structure

Mouse RXD

Microsoft RXD

(C) Bits Structure

(1) Mouse

(2) Microsoft

RXD LINE

Data bitno.

RXD LINE

Data bitno.

(D) Mode Select Timing

(1) Mouse system

RTS

RXD

Reset code
"C8" Bit no.

two byte

"C8" code

Tms Tms

Tmx Tmx

1st 4th2nd 3rd 5th

1st 2nd 3rd

0Td1Td2Td3Td4Td5Td6Td7

Ts

0Td1Td2Td3Td4Td5Td6

Ts

Trd

01234567

Ts Tp

Td Tp

Td Tp

Tp

01

01

(2) Microsoft

RTS

Trd

RXD

Reset code
"CD" Bit no.

"CD"
code

0123456

Ts Tp

7

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

7





Silan
Semiconductors



(E) Photo-couples pulse width

X1(Y1)

X2(Y2)



SC83702

SC83702 I/O PIN EQUIVALENT CIRCUIT

RS,R,M,L,OPT

INTERNALSIGNALRS(R,M,L,OPT)

L,M,R,MS

L
M
R

POWER ONRESET

TEST MODE ENABLE

X1(Y1) PHASE DIGITAL SIGNAL

X2(Y2) PHASE DIGITAL SIGNAL

DQ

CLK

VCC

Tr Tf

OSCI,OSCO

OSC-IN OSC-OUT

RTS,RXD

RTS

VDD

RXD CONTROL SIGNAL

INTERNAL SYSTEM CLOCK

RXD

RTS INTERNAL SIGNAL

X1,X2,Y1,Y2

X1(X2,Y1,Y2)

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

MS

MODE SELECTION

V

CC

R

+

-

PHASE DIGITAL SIGNAL

Rev: 1.0 2000.12.31

8





Silan
Semiconductors



OPTOMECHANICAL MOUSE APPLICATIONS



SC83702

TXD

32768Hz

(3.58MHz)

RTS

RXD

32768Hz

(3.58MHz)

RTS

RXD

RS

1

MS

2

OSCI

3

OSCO

4

RTS

5

RXD

6

V

SS

7

R

8 9

RS

1

MS

3

OSCI

4

OSCO

5

RTS

6

RXD

7

DD

V

OPT

Y2

Y1

X2

SC83702A

X1

L

M

DD

V

OPT

Y2

Y1

X2

SC83702B

X1

16
15
14
13
12
11
10

16

15
14
13
12

SG

10µF

R

SG

2

10µF

R

TXD

V

SS

8

R

9 10

L

11

M

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

9





Silan
Semiconductors





PACKAGE OUTLINE

DIP-16-300-2.54 UNIT:mm

2.54

SC83702

0.25

6.40

3.51

19.4

1.50

0.46

7.62

15 degree

5.083.30

SOP-16-225-1.27 UNIT:mm

0.41

3.95

6.00

5.72

1.27

10.20

9.80

1.95



HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

10



