Technical Projects








The adapter board is pretty simple, one chip, one USB port, a few capacitors and resistors and 2 LEDs


For the chip, use either FT232BM or FT232AM, the former has replaced the latter. They can be purchased and sampled for very little from Saelig--and they wont rip you off for shipping either! None of the parts are that stringently specified. The LED's and their corresponding resistors can be left off if you don't want blinking lights every time.

Soldering the chip on is nontrivial, and requires fine solder or solder paste, a conical tip and solder braid. The pin-pitch is 35mil. Chances are, if you've ever done smd soldering you can do it. The rest of the components are 1206 or larger.

The red electrical tape was necessary to keep the metal case from shorting to one of the traces on this prototype version, and will not be necessary in the future (traces have been moved).

Bill Of Materials
The board costs approximately $10 in components. In quantity, the PCB can be as little as $2 (if done thru 4pcb's barebones service) to as much as $5 if ordered with mask and legend. Assembly for a single sided board is approx. $5 per board, but theres a minimum of 50.
B.O.M. Item Manufacturer desc # req per in qty 1 per in qty 50


FT232BM FTDI USB/Serial chip 1 $5.80 $4.65 saelig
CSTLS6M00G53-B0 Murata 6MHz oscillator 1 $0.35 $0.30 digikey
897-30-004-90-000000 Mill-Max USB connector 1 $1.23 $1.04 digikey
311-27ECT-ND Yageo 27 ohm 2 $0.16 $0.08 digikey
311-1.5KECT-ND Yageo 1.5k 3 $0.24 $0.12 digikey
311-10KECT-ND Yageo 10k 1 $0.08 $0.04 digikey
399-1234-1-ND Kemet 10nF 1 $0.12 $0.12 digikey
311-1176-1-ND Yageo 22nF 1 $0.10 $0.10 digikey
399-1249-1-ND Kemet 0.1uF 3 $0.36 $0.21 digikey
399-1551-1-ND Kemet 10uF 1 $0.19 $0.17 digikey
67-1695-1-ND Lumex LED 2 $0.48 $0.36 digikey
240-1027-1-ND Steward ferrite bead 1 $0.12 $0.10 digikey
Components Total       $9.25 $7.60  
PCB Cost       N/A $2-$5  
Assembly Cost       N/A $5