New ATX Breakout Board PCBs (with some improvements!)

Hello everyone, I’ve got some good news today!

I released a newer version of my ATX Breakout Board. After receiving a lot of requests, I also printed some PCBs (10x blue, 10x red) and will print more after thorough testing of the current revision.

Features and additions added from the older version:

  • Thickened many traces, removed pin headers in the middle of the board and added one behind each binding post (up to 5 output pins per voltage line, with no risk of burning any traces).
  • Added resistors to the USB ports (on the back of the board). You may want to use them for USB identification, as they are cheaper and easier to find than the TPS2513. Adafruit link for more info: https://learn.adafruit.com/minty-boost/icharging
  • Moved LM317 so that you can mount it horizontally + used a footprint with longpads, should you want to solder wires to an external voltage reg + heatsink.
  • Prototyping area added at the top left of the board. Not sure if it will ever come useful, but I had some empty space there. You have easy access to the 3V3 and 5V lines.
  • Moved/rearranged several parts (pot, switch, LEDs) in order to draw shorter and cleaner traces.

New parts list:

  • C1, C3: 0.1uF 0805 SMD capacitors.
  • C2: 1uF 0805 SMD capacitor.
  • F1, F2, F3, F4: 1812 SMD PTC resettable fuses. (Littelfuse ones should work just fine, I used Bourns instead which are a bit larger).
  • J1: 24-pin ATX connector.
  • JP1, JP2, JP3, JP4, JP5, JP6: 5-pin headers, male or female as you prefer.
  • JP7: 3-pin header (voltmeter output).
  • LED1, LED2, LED3, LED4, LED5, LED6, LED7: 0805 SMDs, choose the color you want but make sure to use appropriate resistors. You may not want full brightness and sure enough you don’t want magic smoke.
  • R1, R3, R4, R5, R7: 3.3K ohm, 0805.
  • R2: 330 ohm, 0805 (value may change – double check LM317 voltages or calculate your own).
  • R8: 10k ohm, 0805.
  • R9: 9/10W power resistor, not needed in my case.
  • R6: 1.2k ohm, 0805.
  • R10, R15: 43k ohm, 0805.
  • R12, R14, R17, R19: 51k ohm, 0805.
  • R11, R16: 75k ohm, 0805.
  • T1, T2, T3, T4, T5, T6: binding posts with 4mm hole. You may want some red ones for the positive lines and a black one for GND.
  • U1: LM-317, through hole.
  • U2: TPS2513 from Texas Instruments. If you don’t have it, install resistors R10-R19 for the same functionality (not both!).
  • VR1: 2k ohm, PCB mount potentiometer, 9mm (click)
  • X1, X2: USB female connectors, through hole.
  • SW1: 8x8mm pushbutton (got mine from Tayda.)

I bought all of my components from Tayda Electronics, except for the ATX connector and the PTC fuses (check Sparkfun or eBay!)

Time for some pictures:

Sexy, aren't they?

Sexy, aren’t they? Also, colors!

The whole batch.

The whole batch.

And here’s a fully assembled one (terrible soldering on fuses and LM317 because I recycled them from a previous build):

An assembled board.

An assembled board.

 

PCBs will be available in the store and on Tindie soon.

Cheers!

 

HDC1000 temperature and humidity sensor breakout, with Arduino library!

Some time ago I came across a new chip from TI, the HDC1000. It’s a temperature and humidity sensor with I2C interface and requires little to no additional components. It comes in an 8BGA package: we can all agree it’s pretty small.
Some of the peculiar characteristics of this chip are that it has a DRDYn pin which goes low any time there is a new reading from the chip (so you can precisely time your requests) and that the sensor is located on the bottom of the IC, so that it’s not exposed to dust and other agents that may false the readings. Also, it has an integrated heater that can remove humidity from the sensor.

So I developed a very small breakout board for this chip as well as an Arduino library (yay, my first one! raspberryPi and nodemcu might come next).

The breakout boards.

I learned quite a lot about PCB design and soldering, effectively putting my new hot air station to good use.

Board layout

The boards were again fulfilled by DirtyPCBs, perfect for this kind of small projects.

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LSF0204 breakout board: a bidirectional, multi-voltage level converter!

Hello everyone!

I needed a small, fast and reliable multi-voltage level translator (mainly for connecting ESP8266 boards to the Arduino, got tired of resistor networks pretty quickly) so I built a breakout board for TI’s LSF0204(D).

Datasheet and info here.

The LSF0204 is a nice little chip. It can translate up to 4 signals to and from the following values:

1.0 V ↔ 1.8/2.5/3.3/5 V.
1.2 V ↔ 1.8/2.5/3.3/5 V.
1.8 V ↔ 2.5/3.3/5 V.
2.5 V ↔ 3.3/5 V.
3.3 V ↔ 5 V.

Here’s a picture of the board design:

Board layout

 

It’s very easy to use: connect the reference voltages to VA (1.0-4.5V) and VB (1.8-5.5V), and your signals to A1/2/3/4 or B1/2/3/4. It will translate and output them to the opposite A or B pins.

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