I am finishing up a PCB design for my 16F877 based datalogger circuit =
and getting ready to submit an order to PCB Express.  I am using SMD and =
need solder mask and also want to have the board cut to shape so I am =
using the full production service but only have a guaranteed need for =
5-10 boards.  As such I am trying to make the board as generally useful =
as possible by putting extra pads in for future access to the PIC IO =
pins, etc. =20

In an effort to try to get my per board cost down I thought I would =
offer these boards to the PICLIST with the hope of being able to justify =
placing a larger order.

The board occupies the better part of a 2.5" square with mounting tabs =
and holes to mount into a Hammond 1590Z110 watertight aluminum =
enclosure.  It has through hole pads placed so as to hold a coin cell =
battery holder or use any other power source via wires. =20

The PIC USART is connected to an DB9 using a Maxim (or TI) MAX3221 for =
level shifting.  There is also a Microchip 24LC256 EEPROM and a Linear =
Technologies LT1790 Voltage reference connected to Vref+.  Vref- is =
connected to GND.  All ICs are powered from PIC I/O pins.

The board is designed with a 5 pin ICSP connector and an 8 pin connector =
with power (from PIC IO), ground, and the 6 (all except references) =
Analog inputs.  There are provisions for an RC-debounced 6mm push button =
switch and two (or one bi color) LEDs.  There are two Xtal oscillator =
circuits (Main OSC and T1OSC).  I am running at 4MHz and 32.768kHz, but =
other crystals are probably available that can use the same PCB =
footprints.

As I said, I am planning to be able to use this PCB for future projects =
so I have placed pads to access the PIC I/O pins as well as power and =
ground and the boards will be run using ExpressPCB's Production Service =
with silkscreen and solder masks.  If any of you are interested I will =
sell them for $20 each or $17 for 5+ plus actual USPS shipping costs.  =
If anyone is interested I'll gladly let you see the design so you can =
see if you think it will work for your desired application.  It would =
probably make a great start for someone just getting started in PICs =
that wants to learn to handle SMDs.  On the other hand, if anyone wants =
a starter board without the soldering I will figure up a price for a =
unit with components placed, adding component cost and something for my =
time. =20

I am going to finish adding the extra pads and doing some final labeling =
etc. before hopefully placing my order later tonight so if there is =
interest please let me know ASAP.

Thanks,
Nick

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body