one sided pcb

[Probedude]

Nice job oPossum - nice thick traces from the battery to the IR leds and the emitters of the transistors. Traces feeding IR LED's not also feeding the MCU.

Is there enough voltage with 2AA's to do a emitter follower to boost the base drive to the transistors? If so that would be a nice boost to the IR output.

Edit: doesn't look like it. Need to go to 3AA's.

Hey, you could with a single lipo cell!

[jasonx]

Nice work oPossom
Great idea to have the option of on or off board switch & led.
This is probably going to sound a bit stupid but what is meant by "Split supply capable " ?

Is an "emitter follower" like the ehp version where a transistor drives the other transistors ?

If we used surface mount components could we use three battery's ?

[oPossum]

Split supply would be one battery for the LEDs and another for the microcontroller.

The emitter follower (AKA common collector amplifier) is the transistor between the microcontroller and all the other transistors.

[oPossum]

Compact Hi Power (CHiP)

0.52 x 2.03 inches (AA size)

Drill IR LED holes in the centerline of the battery case to facilitate easy installation and removal.





EAGLE files

[jasonx]

WOW
Your eagle skills never fail to impress me oPossom
Edit : there is no capacitor (unless I missed it ) in this design is it unnecessary with 3 AA's ?

[Probedude]

Nice job as usual!

Now everyone should get together, vote on which one they want a batch of boards made for and then someone get them made!

Having a board house make them the design could then be double sided.

So is there a particular layout/design that's a winner?

[oPossum]

There is no capacitor (unless I missed it ) in this design is it unnecessary with 3 AA's ?

There wasn't room for the 100 uF cap and I am not sure how much benefit there is to having it, so it was omitted.

Here is a board with the 100 uF cap. Some work with a Dremel will be required to make it fit. The cap is smaller than the one used by the EHP (5mm vs 11mm) - see included parts list.

0.52 x 2.09 inches



EAGLE files

[jasonx]

I will have a go at etching the first one at the weekend

[oPossum]

Double sided

0.50 x 2.00 inches (1 sq. in.)





EAGLE files

[magician13134]

Someone (Ladyada I guess) should start a sticky with all the different PCB designs in it, and them pictures of the final if anyone's made it. That'd be pretty helpful to anyone looking to make their own

[Probedude]

oPossum,
You've got two pads really close together where the electrolytic cap is between the IR leds. What's the other pad for?

[caitsith2]

If you look in the schematic, he is covering for 2mm (79mil) lead spacing caps, as well as 2.54mm (100mil) lead spacing caps.

[Probedude]

If you look in the schematic, he is covering for 2mm (79mil) lead spacing caps, as well as 2.54mm (100mil) lead spacing caps.

Thanks, didn't notice that. Some board houses will complain about 2 holes being too close together due to possible breakout and then bit breakage. At first glance these adjacent holes jumped out at me.

I just looked up ExpressPCB's specs and it's:

> A minimum of 0.021" space must remain between adjacent holes. For example, the center-to-center distance between two pads with 0.020" holes must be 0.041" or greater.

[CJM]

Hello,

I would like Opossums board etching,
because of the ISP problem, however, I would like to be the jumper resistors.

I have the whole thing with EAGLE tried, but due to lack of experience nothing.

Could you please according to the circuit times for me?

Maybe the Jasonx?


Thank you






PS:
I hope you understand that G00gl € - English