Pin Description

Pin No.

Pin Name

I/O

Description

10~7, 2~1,

40~39, 29~22,

14~11

R0~R19

O

Keyboard matrix scanning output pins

6~3, 38~35

C0~C7

I

Keyboard matrix scanning input pins

15

VSS

¾

Negative power supply, ground

16

SCROLL

O

Scroll Lock indicator

17

NUM

O

Num Lock indicator

18

DATA

I/O

Bidirectional data transmission line

19

CLOCK

I/O

Synchronous clock signal. Used to clock the transmission data.

20

Fn Select

I

Mini-keyboard select, enables the function if connected to VSS.

21

Macro Key Select

I

Macro Key select, disables the function if connected to VSS.

30

CAPS

O

Caps Lock indicator

31

RESET

I

Chip reset input. Active low. Built-in power-on reset circuit to reset the en-

tire chip. Chip can also be externally reset via RESET pin.

32

VDD

¾

5.0V positive power supply

33

OSC1

I

System clock input; 58.3k

W resistor connected for RC OSC

34

NC

¾

No connection

Absolute Maximum Ratings

Storage Temperature ...........................

-50°Cto125°C

Operating Temperature ..........................

-25°Cto70°C

Note: These are stress ratings only. Stresses exceeding the range specified under

²Absolute Maximum Ratings² may

cause substantial damage to the device. Functional operation of this device at other conditions beyond those

listed in the specification is not implied and prolonged exposure to extreme conditions may affect device reliabil-

ity.

Electrical Characteristics

Ta=25

°C

Symbol

Parameter

Test Conditions

Min.

Typ. Max. Unit

Conditions

Operating Voltage

¾¾

3

5

5.25

V

Operating Current (RC OSC)

5V

¾

2.5

5

mA

Input Low Voltage

5V

¾

0

¾

1.5

V

Input High Voltage

5V

¾

3.5

¾

5V

Sink Current (C0~C7, R0~R19, DATA, CLOCK)

5V

16

25

¾

mA

Source Current (C0~C7, R0~R19)

5V

-8

-16

¾

mA

Source Current (Scroll, Num, Caps)

5V

-2.5

-4

¾

mA

LED Sink Current (Scroll, Num, Caps)

5V

10

18

24

mA

Internal Pull-high Resistance (C0~C7, R0~R19)

5V

¾

512

20

k

W

Internal Pull-high Resistance (DATA, CLOCK)

5V

¾

2

4.7

8

k

W

Internal Pull-high Resistance (RESET)5V

¾

25

50

75

k

W

System Clock (RC OSC)

5V

¾¾

4

¾

MHz

HT82K628A

Rev. 1.60

2

April 16, 2004