This list contains awesome pcb-design related things. If you know some cool thing that's related to electronics design automation (EDA) or PCB design, feel free to add it. Pull requests welcome.
- LM317T variable linear power supply, widely available
- LM78xx fixed voltage linear power supply, available in 3.3V, 5V and 12V (and many other voltages)
- LM2596 Buck Converter, variable output voltage 1.23V - 37V, 3A max output, 40V max input
- LT1767 Monolithic 1.5A Step Down Regulator, 1.25 Mhz Switching frequency, Fixed output voltages of 1.8V, 2.5V, 3.3V and 5V, 2% output tolerance
- HT7333/HT7833 Battery-friendly LDO (low Iq)
- LM1117 One of most popular "jellybean" SMD LDO, available from many vendors
- TPS61021 Step-up that can work from single cell (up to 1.5A)
- TLV61220 Step-up that can work from single cell (more efficient, but less current)
- ME7660 Cheap charge pump for negative rail (opamp, analog switches, etc)
- MIC2920 Low Dropout Regulator with 40mV dropout voltage at light load and 370mV @ 250mA, current and thermal limiting, -20V reverse polarity protection, 60V transient protection
- W25Q series SPI flash memory
- STM32F103C8T6 Cheap microcontroller, same as on bluepills, 48 Mhz, ADC, I2C, SPI, USB
- STM32F417 Bigger and faster alternative for the F103, F417/F427 have crypto hardware, F407 does not, 168 Mhz, ADC/DAC, I2C, SPI, USB, Ethernet
- STM32F767 Bigger and even faster than the F417, Nucleo Board available
- STM32G0 series Next generation alternative for STM's F0 series.
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FQP30N06L Beefy logic level mosfet VDSS 60V, ID 32A, Ron 35mOhm, Vgsth < 2.5V, around 10A @ 3.3V Vgs
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BSS806NE Super low threshold voltage, small package, Vgsth < 0.75V, VDS 20V, ID 2.3A
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LTC2950 Pushbutton On/Off controller, adjustable turn on/off timers, debounced, µController interrupt & turn off pins, 2.7V - 26.4V
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IS31FL3741 39x9 dot matrix led driver, drives 351 leds or 117 rgb leds, I2C interface
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IRFP260 Really super enormously beefy Mosfet. Suitable for linear operation, e.g. in electronic loads. TO-247 package
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FQL40N50 Linear Mosfet, but even beefier than the IRFP260
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KIA50N03/KIA50N06 Very cost efficient beefy (30/60V and 50A!) and reasonably low Rds(on) N-FET in DPAK case
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AON7418 High-Current, Low Rds(on), N-Channel Mosfet
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IXTA10P50P Beefy DC-rated P-Channel Mosfet, 500V, 10A (IXTA, ISTH, ISTP, IXTQ for various packages)
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FQB8N60C Similar rating to IXTA10P50P, both used in Agilent SMU
- ADL5544 Wideband RF gain block, 30 MHz - 6 GHz, fixed gain of 17.4 dB
- SKY13345-368LF 0.1-3.5 GHz SP3T Switch
- AS211-334 0.1 to 4.0 GHz pHEMT SPDT Switch
- LM358 Simple dual OpAmp, not great, not terrible
- OPA2206 ±40V Precision OpAmp, similar to LM358, but better in every way
- LMV611 Rail-2-Rail OpAmp up to +5V
- OPA2277 Dual Precision OpAmp, 10µV Offset, 0.1µV/°C Drift, +36V/±18V Supply Range, affordable at ~1€
- MCP9700 Temperature Sensor
Distributors sell all sorts of connectors. There is a special connector for almost any application you could think of. However most of the time you don't need anything special, you just need something that works. Often a simple pin header/socket does the job. But sometimes your applicaiton is just a tiny bit more demanding. The connectors in this category fulfil such purposes. They're not special-purpose, but they do have some advantages over regular pin headers.
- Molex 6410 Series PCB pin headers (mates with 2695 Series connectors) are polarized connectors that are somewhat compatible with pin headers (both have a 2.54mm spacing). If you use both socket and connector you can't plug things in the wrong way. Connector Part Number: 22012xx1 where xx is the number of pins e.g. 04 to get 4 Pins. Pin header part number is 22272xx1, where xx is the number of pins. They can also be found under the name KF2510 on LCSC. The crimping contacts require this tool.
- Ningbo Kangnex Elec WJ15EDGK-3.81 Series They are pluggable screwterminals and can deal with quite a bit of current (5A and more per pin). They are also polarized so plugging them in the wrong way is impossible. The PCB-side receptacle is called WJ15EDGRC-3.81-4P, where 4P gives the number of pins (4 in this case). The screw-terminal-plug is called WJ15EDGK-3.81-4P. Once again the 4P means 4 pins. They are also availble in right-angle versions (WJ15EDGVC-3.81-4P and WJ15EDGKA-3.81-4P). There is also a version that can be locked in place with screws (WJEDGKM-3.81-4P and WJ15EDGRM-3.81-4P). They are available in many pin counts at lcsc.com. Phoenix Contact (and many other companies) has a similar product, but their product numbering sucks, so it isn't listed here.
- NHD-12232KZ-NSW-BBW-P Graphic LCD, 128x32 Pixels, fairly cheap ~14€, similar form factor to 16x2 text LCDs, 8800/6800 compatible
- PCA9306 I2C Level shifter IC
- MT6815 by Magn Tek Fairly affordable, (but difficult to source) absolute magnetic rotary encoder IC
- Digikey they have pretty much everything, US based
- LCSC very cheap and good assortment of parts, from China
- Mouser another distributor
- Farnell another distributor
- RS Components They also sell lots of mechanical parts such as motors, industrial automation equipment, etc
- PCB Shopper compares many pcb manufacturers
- JLCPCB Super affordable PCBs from China, multiple colors including matte black, 2$ for 5 PCBs
- Aisler High Quality PCBs from Germany
- Oshpark High Quality PCBs from the US, "After Dark" style, can do Flex-PCB at $10/square inch
- Elecrow
- Seeed
- PCBWay
- PCB Shopper compares many pcb assemblers
- JLCPCB
- Elecrow
- Seeed
- PCBWay
- KiCAD free and open source EDA software, had some pretty big updates and improvements recently
- geda free and open source
- Fritzing free and open source if you compile it yourself. A binary download costs 9 €.
- EAGLE free for smaller boards
- Target 3001! not open source, but free for small personal boards
- Altium Designer, not free or open source
- Orcad, not free or open source
- TopoR Free license for small boards of hobbyists, very funny curvy traces autorouter
- Wireviz Open source tool to visualize wire harnesses
- wavedrom Open source tool to draw timing diagrams
- bitfield open source bit field/register diagram renderer
Please note that the following guidelines/recommendations are the result of my own experience designing pcbs.
- Add test pads or preferably actual test-pins for power, ground and important signals
- Mark important test pins with a descriptive name if possible (e.g. "temperature", "V_out", "threshold set")
- mark all pin names on the PCB
- mark all important connectors, e.g. "Sensor-Input", "UART", "I2C", even obvious things such as "USB"
- mark polarity of all polarized components such as diodes, connectors, electrolytic capacitors
- add 3 fiducials for better PCBA using computer vision, worst case 2 is sufficient
- clearly mark pin 1 of all ICs and connectors, preferably additionally mark IC footprints the same way the IC itself is marked (e.g. chamfered edges or pin 1 marking)
- Put reference designators for every component on the PCB if you have the space. Otherwise create a pdf or printout of the board that contains reference designators.
- Don't use text smaller than 0.8mm
- Add more test pads for ground (and other voltages/signals)
- Put polarity icon(s) on the silkscreen next to power connections. In particular Barrel Jacks.
- Put minimum and maximum input/output voltage on the silkscreen next to power connections. E.g. "12-24 VDC" or "48 VAC". If you have tighter voltage tolerances than 10% add it to the silkscreen.
- Put max current draw or max current sourcing capability on the silkscreen next to power connections. e.g. "3A"
- Put version number and date on the silkscreen. E.g. "v1.0 November 2020" or "V2 07/2015"
- Add even more ground test pads
- Round all external pcb corners to prevent injury. Your PCB WILL be handled by humans at some point. Don't skimp on this. Any injuries from sharp edges will be your fault.
- Depending on PCB size and weight, place M2.5, M3 or M4 mounting holes on opposite ends of the PCB or preferrably in all 4 corners
- More. Ground. Testpads.
- Use 0603 SMD components whereiver possible for automated assembly.
- avoid traces under components (risk of short due silkscreen wearout during prototyping/rework) which is hard to debug, interference
- Try to use E12-series resistor, capacitor and inductor values first, bevore going to E24, E48, etc.
- Create a BOM containing each part's reference designator, part name/number and resistance/capacitance value, manufacturer part number, seller link
- When designing break-away sections, use a slot of at least 2mm width, for tabs add mousebites/vias in line with the board edge do not recess them into the board. Make sure whoever breaks it sands it down.
- Create at least an A4 summary documentation, which should include a picture of the assembled board.
- For microcontroller boards add a UART/JTAG/SWD pinout for debugging somewhere on the board
- Make LEDs as dark as possible and as bright as necessary. Status LEDs should not be bright enough to illuminate anything, only bright enough to recognize they're on.
- Status LEDs should emit diffuse light, if possible add a diffusor like milky-white acrylic glass to your enclosure
- Add a power LED that shows when the device is receiving power
- Add red LEDs that indicate devices that record things such as video, audio or GPS tracks. Bonus points for devices that record other data such as acceleration data, voltage, current and others. Continuous red means its recording.
- Don't let LEDs blink unless there is a fault. Faults should always be indicated by blinking LEDs. One exception to this guideline are status LEDs for things like UART TX/RX line or Ethernet Connections.
| Color | Meaning |
|---|---|
| green (continuous) | - status is nominal - device/function is turned on |
| yellow (continous) | - abnormal status - device pausing abnormally - possible fault indication - warning |
| red (continuous) | - camera/microphone/device is recording - error state, immediate attention is not required |
| red (blinking) | - device is stopped or stopping due to critical fault (e.g. emergency stop was pressed). Immediate Attention is required. |