TOPRO TP6312 User Manual

TP6312

1/4 TO 1/11-DUTY VFD CONTROLLER/DRIVER

General Description

The TP6312 is a VFD (Vacuum Fluorescent Display)
controller/driver that is driven on a 1/4 to 1/11-duty
factor. It consists of 11 segment output lines, 6 grid
output lines, 5 segment/grid output drivelines, a
display memory, a control circuit, and a Key scan
circuit. Serial data is input to TP6312 through a
three-line serial interface. This VFD controller/driver
is ideal as a peripheral device of a single-chip
microcomputer.

Ordering Information

TP 6312

Footprint
Version
Package Type

Features

 Multiple display modes (11-segment & 11-digit to

16-segment & 4-digit)

 Key scanning (6 × 4 matrices)
 Dimming circuit (eight steps)
 High-voltage output (V
 LED ports (4 chs, 20 mA max)
 General-purpose input port (4 bits)
 No external resistor necessary for driver outputs

(P-ch open-drain + pull-down resistor output)

 Serial interface (CLK, STB, D

Package Type

Footprint

F: LQFP
S: 2.0 mm
L: 3.2 mm

– 35V max)

DD

IN

, D

OUT

)

Block Diagram

DIN

DOUT

CLK

STB

R

Key1

to

Key4

4

Serial I/F

OSC

Command decoder

Display memory
16bit x 11 word

Timing generator key

scan

Key data memory

(4x6)

Dimming circuit

16 11

16-bit output latch16-bit output latch

11 6

Seg1

Segment driverSegment/grid driverGrid driver

5

5

Data selector

5

Seg11

Seg12/Gird11

Seg16/Gird7

Grid1

Grid6

SW1

to

SW4

4

4 bit latch

4 bit latch

1

LED

LED

VDD VSS VEE

(+5V) (0V) (-30V)

4

Version 1.1 Page 1 of 9 http://www.topro.com.tw
September 2003

TP6312

Pin Configuration (Top View)

Grid 4

Grid 3

Grid 2

Grid 1

DD

V

LED 4

LED 3

LED 2

LED 1

VSS

OSC

44 43 42 41 40 39 38 37 36 35 34

Use all the power pins.

1/4 TO 1/11-DUTY VFD CONTROLLER/DRIVER

EE

Grid 6

Grid 5

33

1

SW 1

Seg15 / Grid 8

Seg16 / Grid 7

30

31

32

2

3

4

SW 2

SW 3

SW 4

V

Seg14 / Grid 9

Seg13 / Grid 10

Seg12 / Grid 11

26

27

28

29

5

6

7

8

OUT

DIN

CLK

VSS

D

Seg9

Seg10

Seg11

23

24

25

Seg8

Seg7

Seg6 / KS6

Seg5 / KS5

Seg4 / KS4

Seg3 / KS3

Seg2 / KS2

Seg1 / KS1

V

DD

KEY 4

KEY 3

12 13 14 15 16 17 18 19 20 21 22

9

10

11

STB

KEY 1

KEY 2

Pin Description

Pin No Symbol Pin Name Description

6 DIN Date input

5 D

Date output

OUT

9 STB Strobe

8 CLK Clock input

44 OSC Oscillator pin

/KS1 to

Seg

Seg

Seg

1

Seg

6

/Grid11 to

11

16

/KS6

/Grid7

High-voltage output
High-voltage output

(Segment)

High-voltage output

(Grid)

High-voltage output

(Segment/grid)

15 to 20
21 to 25 Seg7 to Seg11
37 to 32 Grid1 to Grid6

26, 28 to 31

42 to 39 LED1 to LED4 LED output CMOS output. +20 mA max.
10 to 13 Key1 to Key4 Key data input

1 to 4 SW1 to SW4 Switch input

14, 38 VDD Logic power

7, 43 VSS Logic ground Connect this pin to system GND.

27 VEE Pull-down level VDD – 35 V max

Inputs serial data at rising edge of shift clock,
starting from the lower bit.
Outputs serial data at falling edge of shift clock,
starting from the lower bit. This is N-ch open-drain
output pin.
Initializes the serial interface at rising or falling edge
to make TP6312 waiting for reception of command.
Data input after STB has fallen is processed as
command. While command data is processed,
current processing is stopped and serial interface is
initialized. While STB is high, CLK is ignored.
Reads serial data at rising edge, and outputs data at
falling edge.
Connects a resistor to this pin to determine the
oscillation frequency to this pin.
Segment output pins (Dual function as Key source).

Segment output pins.
Grid output pins.
These pins are selectable for segment or grid

driving.
Data input to these pins is latched at the end of

display cycle.
These pins constitute 4-bit general-purpose input
port.
5V ± 10%

Version 1.1 Page 2 of 9 http://www.topro.com.tw
September 2003

TP6312

1/4 TO 1/11-DUTY VFD CONTROLLER/DRIVER

Functional Description

Display RAM Address and Display Mode

The display RAM stores the data transmitted from an
external device to TP6312 through the serial interface,
and is assigned addresses as follows, in units of 8
bits:

Seg

Seg4 Seg8 Seg

1

00HU 01HL 01HU DIG1

00H

L

02HL 02HU 03HL 03HU DIG2
04HL 04HU 05HL 05HU DIG3
06HL 06HU 07HL 07HU DIG4

08HL 08HU 09HL 09HU DIG5
0AHL 0AHU 0BHL 0BHU DIG6
0CHL 0CHU 0DHL 0DHU DIG7
0EHL 0EHU 0FHL 0FHU DIG8
10HL 10HU 11HL 11HU DIG9
12HL 12HU 13HL 13HU DIG10
14HL 14HU 15HL 15HU DIG11

b

b

0

b

3 b4

7

XX HL XX HU

Lower 4 bits Higher 4 bits.

12

Seg16

Key Matrix and Key-Input Data Storage
RAM

The Key matrix is of 6 × 4 configuration, as shown
below.

KEY1

KEY2

The data of each Key is stored as illustrated below,
and is read by a read command, starting from the
least significant bit.

Key

Key4Key1 Key4

1

/ KS1 Seg2 / KS2

Seg

1

Seg3 / KS3 Seg4 / KS4

Reading s eque nce

Seg5 / KS5 Seg6 / KS6

b0 b3 b4 b7

LED Port

Data is written to the LED port by a write command,
starting from the least significant bit of the port.
When a bit of this port is 0, the corresponding LED
lights; when the bit is 1, the LED goes off. The data
of bits 5 through 8 is ignored.

---- ---- ---- ---- b3 b2 b1 b0

LED1

Don't care

LED2
LED3
LED4

On power application, all LEDs are unlit.

SW Data

The SW data is read by a read command, starting
from the least significant bit. Bits 5 through 8 of the
SW data are 0.

MSB LSB

0 0 0 0 b3 b2 b1 b0

KEY3

KEY4

SW1
SW2
SW3
SW4

Commands

Seg1/KS1

Seg2/KS2

Seg3/KS3

Seg4/KS4

Seg5/KS5

Seg6/KS6

A command sets the display mode and status of the
VFD driver.
The first 1 byte input to TP6312 through the D

IN

pin
after the STB pin has fallen is regarded as a
command.
If STB is high while a command/data is transmitted,
serial communication is initialized, and the
transmitting command/data is invalid; however, the

Version 1.1 Page 3 of 9 http://www.topro.com.tw
September 2003