Overview
Using a prototype board for microcontroller hardware and firmware testing is quicker and safer than solely placing and wiring all components on breadboard. We can design and make our own simple prototype board by hand with a conventional single side PCB.
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| Finished PCBA |
I have some PIC microcontrollers and a dozen of components that left from previous projects. So I decide to make my own test board for PIC18F4550 microcontroller with those components. Conventionally I use a single sided PCB with toner transfer method to make a PCB. However PCBWay offers sponsors PCB projects for electronics hobbyists and students. So it's possible to make a standard multilayer PCB.
I designed a small size PCB for PIC18F4550 or other 40-pin compatible PIC microcontrollers with an on-board PICKit2 device programmer because I have a dozen of PIC18F2550 for making a PICKit2 USB programmer.
On this board I putted some major functional blocks,
- +5.0VDC and +3.3VDC regulated power supply
- clock and reset pin
- RS-232 to TTL converter using max232
- USB connector for USB communication for PIC18F4550
- ADC inputs using variable resistors and LM35 analog temperature sensor
- I2C RTC (ds1307) and AT24C08 EEPROM
- Four-bit LCD (HD44780 compatible)
- output LEDs
- input switches
- 40-pin male header for external circuit connections.
I also placed a male rectangle box header for programming any AVR microcontrollers using PICKit2 and AVRDude IDE.
Schematic
I use protues VSM to design schematic for this PCB because it's light-weight, user-friendly and simple to use. Its schematic contains three A4-size sheets.
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| Schematic Sheet #1 |
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| Schematic Sheet #2 |
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| Schematic Sheet #3 |
Some components are duplicated because they are IC socket and IC.
Printed Circuit Board
Protues also has PCB design with many device symbols and footprints. However we can install our preferred device from third party company such as snapeda.
This double-sided PCB is no worry about DIY fabrication because it's sponsored by PCBWay. The size of this PCB is 15cmx20cm that is affordable to fabricate.
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| Top Side |
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| Bottom Side |
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| Top Silk |
Some electronics hobbyists can fabricate this double PCB at home but it's complex and hazardous.
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| Top 3D View |
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| Front 3D View |
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| Back 3D View |
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| Left 3D View |
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| Right 3D View |
Some devices doesn't exist in Protues VSM. Hence I download them from snapeda. Snapeda has over one million device libraries including schematic symbols, footprints and 3D objects. Their libraries are compatible with Protues, Cardence, Altium, KiCAD, Eagle etc. Their 3D objects are compatible with Solidwork, FreeCAD, etc. They are free of charge but we have to register an account before we get it.
PCB Fabrication
This PCB is offered by PCBWay since it's a sponsor project. PCBWay is a long term and well known one-stop service provider including PCB fabrication, PCB assembling (PCBA) etc. Their service and price are reasonable. Beside their standard PCB they offer advanced PCB, flex PCB, CNC parts and 3D printing parts.
Most of PCBs are fabricated within 24 hours with a few days of delivery time. All PCB are checked and verify before sending to fabrication process (pre-production check). Their engineer contact us very soon if their are any problem or doubt.
PCBWay also offer a low cost PCB fabrication of the size 10cmx10cm. We can order it between 5 and 10 units for only 5USD. They are standard double sided PCB with solder mask, silkscreen, circuit testing etc.
For a large scale demand we can order their PCB assembly service at reasonable price for any projects.
It took no more than one week to get my PCB order. It was shipped using DHL.
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| DHL package |
The package is well prepared and the PCBs are well protected.
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| PCB Package from pcbway.com |
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| Received PCBs |
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| Received PCBs |
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| Five Units of PCB |
We can choose other solder mask and silk screen colors.
PCB Assembling
It takes one day of solder this board by hand with some tools, electrical solder iron, tin lead, etc. After I finished soldering I need to clean all flux residue left from tin lead soldering, using gasoline or thinner with a smooth brush.
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| PCB pre-soldering |
I already test the circuit but the firmware has not yet been tested. So need to write some sample codes for this prototype board.
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| Finished PCBA #1 |
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| Finished PCBA #2 |
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| Finished PCBA #3 |
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| Finished PCBA #4 |
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| Finished PCBA #5 |
