TH/SMD Protoboard, Adj Reg, 9V Battery

I just released a new prototyping board. It features an SMD/TH prototyping
area, adjustable regulator and a receptacle for a 9V battery.
Pictures are at

The schematic is basically the same as the adjustable regulator on
the PICO. I will have the datasheet and schematic on the site in
the next couple of days.

(* jcl *)


Price/mAh the worst possible choice for a power supply. Would be nice with a holder for 4 AA batteries, though.

Yeah, yeah, I know that would make it larger.

For 3.3V and 5V it is very wasteful. It can be used at higher voltages by changing
a resistor (although most people will do 3.3V and 5V systems).

If the 4AAs are on the PCB the majority of the PCB area is consumed by the holder.
I figured that running two wires to the battery holes would be better. Maybe I
should add a two pin header in parallel with the 9V battery.

I was thinking of the following additions –

2AAs and a simple TH boost converter (3.3V or 5V)
Add a TH inverter for a negative voltage – ±5V, ±3.3V
Add a low Iq converter (SMD)

(* jcl *)

Add a low Iq converter

I think one of the posters over the weekend used one of these. Seems to have worked quite well on him/her.

Since I was doing a design panel I decided to prototype a new version of the
board with two AAs and a boost converter. The boost converter is 88-94% efficient
and runs at 1.2MHz.

Preliminary webpage is at --

(* jcl *)