Close

Even tinier

A project log for 7 Segment Hex Module using PIC16F18446

Two digit (8 bit) sevent Hex segment display using a microcontroller

John LonerganJohn Lonergan 04/06/2021 at 20:540 Comments

I got the boards for my new 7 seg modules, but whilst they are small and versatile I immediatley decided I also wanted a super "tiny" variant. Super tiny meaning no bigge than the necessary footprint of the two 7 seg displays themseves.

So last night I redrew the board so that the entire PCB sit's within the outline of the two 7 segment displays.

What had stopped me before was that the need to connnect the module to the breadboard meant using a further row of pins (and more real estate). My existing design used long stackable headers for that purpose and is as I say pretty versatile as the stackable headers mean I can wire up the modules from above using jumper wires. I'll solder one up to show later this weel.

But last night it occured to me that if I mount the PIC using wire wrap SIL turned pin headers then the pins of the "ic socket" itself would be long enough to make the breadboard connection. No need for further rows of long headers. 

I also decided to mount the two current limiting resistors underneath the PIC chip. If the the PIC is sitting in some SIL headers then there's loads of space for a couple of resistors sitting underneath the PIC. 

This meant that I could cram then entire thing into a 25mm x 19mm board.  

JLCPCB made another £10.62 out of me and I'm having a whiskey sour to celebrate. 

It' pretty tight but I like the look of this.... 

Discussions