PT6321

V1.0

5

August, 2009

PIN DESCRIPTION

Pin Name

I/O

Connects to

Description

Pin No

AD1~4

O

Fluorescent tube

anode electrode

Fluorescent display tube anode electrode drives output.

Directly connected to fluorescent display tube. No pull-down

1,2,79,80

SEG1~35

O

Fluorescent tube

anode electrode

Fluorescent display tube anode electrode drives output. Directly

connected to fluorescent display tube. No pull-down resistor is

3-37

Power supply

38,78

COM1~24

O

Fluorescent tube

grid electrode

Fluorescent display tube grid electrode drives output.

Directly connected to fluorescent display tube. No pull-down

39-62

PGND1~2

Power supply

High Voltage GND pin

63,76

LGND

Power supply

Logic GND pin

64

OSC0

I

Connect R and C externally. The RC time constant depends on

the VDD voltage used. Set the target oscillation frequency to 2

MHz.

65

OSC1

O

(RC oscillation circuit) See

Application Circuit)

66

Reset input.

Setting this pin to "Low" initializes all the functions.

The initial status is as follows.

• Address of each RAM….. address "00"H

• Data of each RAM….. Content is undefined

• Number of display digits….. 24 digits

• Contrast adjustment….. 8/16

• All lights ON or OFF….OFF mode

• All outputs….. "Low" level

/RESET

I

Microcontroller

(Circuit when R and C are

connected externally) See

application Circuit

67

/CS

I

Microcontroller

Chip select input

Setting this pin to "H" disables serial data transfer.

68

/CP

I

Microcontroller

Shift clock input.

Serial data is shifted on the rising edge of /CP.

69

DA

I

Microcontroller

Serial data input (positive logic).

Input from LSB.

70

Power supply

Logic Voltage Pin

71

P1~4

O

LED drive control

terminals

General port output.

Output of these pins in static operation, so these pins can drive the

72-75