1 2 3 4 5 6 7 8

A

B

C

D

87654321

D

C

B

A

Title

Number RevisionSize

A3

Date: 2-Jan-2003 Sheet of File: M:\src\..\z8_vfd12_pulse_7805.sch Drawn By:

11 Digit VFD display with AC Filament drive

C021 EB1Kev

of 1

C1100n

RxD+ 1

RxD- 2

TxD+ 3

V+ 4

V+ 5

TxD- 6

GND 7

GND 8

CON1

Pow

er+C

omm

s

EC1220u/25v

+12v

EC2220uF/10V

R1470R

LED15V

D11N4004

VCC

GND

Vcc

5

GN

D14

P2015

P2116

P2217

P2318

P241

P25 2P26 3P27 4

P31 8

P32 9P33 10

PO0 11

PO1 12

PO2 13

Xtal17

Xtal26

U2

Z86E

08-1

2PSC

GNDVCCBP1100n

X110MHz

C622p

C722p

GND GNDR54K7

VCC

GND

VB

B1

SERIAL DATA OUT2

OUT 203

OUT 194

OUT 185

OUT 176

OUT 167

OUT 158

OUT 149

OUT 1310

OUT 1211

OUT 1112

BLANKING13

GN

D14

CLK15 STROBE 16OUT 10 17OUT 9 18OUT 8 19OUT 7 20OUT 6 21OUT 5 22OUT 4 23OUT 3 24OUT 2 25OUT 1 26SERIAL DATA IN 27VDD 28

U3 UCN5812AF(28)

GND

VCC

R6100R

GND

SBLANKSCLK

STROBE

SDIN

SBLANKSCLKSTROBESDIN

Cat

hode

04

Cat

hode

16

Cat

hode

28

Cat

hode

310

Cat

hode

412

Cat

hode

514

Cat

hode

616

Cat

hode

718

Cat

hode

820

Ano

de A

22

Ano

de B

19

Ano

de C

17

Ano

de D

11

Ano

de E

9

Ano

de F

7

Ano

de D

P15

Ano

de C

omm

a13

Ano

de H

yphe

n24

Ano

de G

5

NC

2

Cat

hode

921

NC

3

Cat

hode

10

23

NC

25

Vfil1 1

Vfil2 26

VFD1VFD_ZD1880

C2100n

C3100n

C4100n

C5100n

VCC

GND

EN1

C1+2

C1-4

V+ 3

C2+5

C2-6

V- 7

TX1 IN 12TX1 OUT15

TX2 IN 11TX2 OUT8

RX1 OUT 13

RX2 OUT 10

RX1 IN14

RX2 IN9

ON/OFF 18GND 16

VC

C17

U4MAX222

R7 33R

R8 33R

R9 33R

R10 33R

CO

M1

R1

2R

23

R3

4R

45

RS1RSIP5-1K

VCC

GND

R1133R

GND

EBLANKELATCH

ECLK

ERESET

BP2100n

GND

LED2Active R12

270RVCC

BLANKGNDLATCHGNDCLOCKGNDRESETGND

CON2

Control

R13820R

R2

470R

20-bit VFD Driver & Latch

5 Volt Regulator

RS232C COMMUNICATION INTERFACE

DISPLAY CONTROLLER DIGITAL COUNTER/LATCH SIGNALS

VFD CONTROL and DISPLAY

TRIG 2

Q3

R4

CVolt5

THR 6

DIS 7

VC

C8

GN

D1

U5LM555

R3470R

R4470R

C810n

C910n

GND

VCCVCC

f=61KHz

VCC

GND

69T51T

Xfmr1 Construction.

The transformer is wound onto a pressed ferrite powdered bobin measuring 15mm high, 5mm inner barrel and 10mm outer edges.

Primary winding: 69 Turns of 32 gauge enamelled wire or thinner.

Secondary winding: 51 Turns of 32 gauge enamelled wire or thinner over the top of the primary winding.

The ratio of 69:51 should be maintained. If twice as many winds can be applied to the bobin then drive current will be reduced and the need for the LM395 driving transistor can be removed. The NE555 will be capable of driving the transformer direct although a Back-EMF diode across the primary will be needed for the NE555's protection.

www.cate.com.au

U6LM395

T1VFD_XFMR

D312V

D4SM4T33CA

1

2

JP1DSP MODE

PS1

POLYSWITCH (0.5A)

Vin1

GN

D2

Vout 3

U1VOLTREG