BOE VFD48-1202FN Assembly Instructions Manual

USB Powered

VFD48 Analog-style Unique Round VFD Clock

Assembly Instructions

V1.0

[e-mail]

HTTP://vfdclock.jimdo.com

2

Contents

Notice....................................................................................................................................................................................1

Building it .............................................................................................................................................................................2

Preparing.......................................................................................................................................................................2

Step 1: USB Power In and MCU part...........................................................................................................................2

Step 2: RTC part............................................................................................................................................................4

Step 3: Filament Driver part..........................................................................................................................................5

Step 4: Negative High Voltage part circuit....................................................................................................................6

Step 5: CDS and IR part................................................................................................................................................7

Step 6: VFD drive Chip.................................................................................................................................................8

Step 7: First Testing ......................................................................................................................................................9

Step 8: Cleaning Circuit Board...................................................................................................................................10

Step 9: Buzzer part......................................................................................................................................................11

Step 10: Buttons part...................................................................................................................................................12

Step 11: Test the buttons, buzzer, and VFD panel.......................................................................................................12

Step 12: Solder the VFD48 Panel...............................................................................................................................13

Step 12: Solder the Extras:..........................................................................................................................................13

Circuit and PCB..................................................................................................................................................................16

1

Notice

For assembling the VFD48 clock you need to have the skill of

soldering SMD components. We use a Hakko FX-888 Soldering Station

(with CF2 Iron Head) and a Hot air blower station. We use
183℃(degree C)low melt temperature solder wire S60, 0.5mm(Dia.),

Brand Almit.

For how to solder the SMD components, we recommend:

https://www.hakko.com/english/tip_selection/type_bc_c.html

https://www.hakkousa.com/video/

Please do not change any equipments of the KIT or you may not

be able to get the clock working.

If already have the skill of soldering the SMD components, it

is easy for you to assemble the clock, please check the circuit

diagram carefully and follow the steps shown blow.

We do not recommend you to solder the components in random order

or if it has problems you will need more time for de-soldering

and debug, we recommend you follow the steps in this instructions

that you can do part test after finished each step.

For more info & update, please visit HTTP://vfdclock.jimdo.com

Or contact us: [e-mail]

Thanks for choosing our product.

2

Building it

Well, because of the circuit is module based and not very

complicated, all you need to do is get all the components in the

right position and make sure no short before you plug the power

in. We will show the soldering steps blow.

Preparing

1. Please print out the PCB installation diagram by yourself,

the Circuit diagram is no need for soldering job, print it or

not depends on you(Note: May only have the paper circuit diagram

in the KIT with no digital version provide.);

2. Check all the components in the kit bag, make sure nothing

is missing (You can do this on a A4 white copy paper);

3. We recommend using a soldering station and small soldering

tip for soldering this kit (we use F2 or CF2 type tip). If you

have a hot air gun(or Hot air blower station) tool for soldering,
that will be great. We recommend using ~180℃ type soldering tin

for this job. Please do not use the high temperature soldering

tin in this project, you may damage a lot of SMD components or

the PCB;

Step 1: USB Power In and MCU part

Solder the [USB Power In] part first; This part contains a USB

socket and a 1206 size RESETTABLE fuse.

For soldering the USB socket, we recommend solder the 5 middle

3

Pins first, then flip the PCB to the other side and use long flat

nose pliers to band the two fixed legs of the USB socket a little

bit close then solder these two fixed legs.

Then solder the 1206 FUSE, usually in golden color with mark [4

]

on it, easy to find.

After soldering these two components, you can plug the USB power

in and measure the fuse output pad to see if it has 5V output.

The next part of this step is soldering the main MCU chip, it

is a LQFP32 package MCU with [105K6T6](or 005K6T6) mark on it.

Please check the first legs position. For soldering the QFP stuff

like this, we recommend that you use a short Polyimide Tape to

glue the chip on the correct location of the PCB first, then solder

one corner, if all fine, solder the other side pins in the next,

4

then the rest sides' pins.

After finish soldering the MCU chip, double check all the pins,

make sure no short. Then solder two capacitors blow the MCU

chip(1uF and 0u1F), the 1uF one is the key component, must be

installed or the MCU won't work.

Step 2: RTC part

In this step, you need to solder the RTC (Real Time Clock) part

components, it contains 3 components, the major one is the RX8025

RTC all in one chip in SOP14 package, it may have the mark RX8025AC

or RX8025T mark on the surface depends on the kit's version. Please

solder the chip in the correct direction, please control the

iron's temperature, and solder it fast, and take care of the

ESD(Electro Static Discharge) control.

Then solder the diodes D1 in sot-23 package with [5C6] mark and

the 0u1F capacitor.

(*Please note that RX8025AC and RX8025T are not the compatible

chips, if damaged the chip ,please use the same mark chip to

replace).

You can try to plug the 5V USB power, if the RTC chip and the

MCU in working, you can find the 1Hz(or 2Hz) signal in the 1Hz

testing pad(you can use oscillograph if you have).

If you want, you can install the CR1220 Battery Socket too at

this step, recommend to cut the left&right pads of the socket

a little bit short for easy to solder.(Note: The straight metal

pad part in the socket is the [+] pad, do not go invert;