4
JP6 - Header 2x2
JP10, JP12, JP13 - installed as one Header 3x2
JP14 - Header 3x2
JP18 - Header 2x1
JP19 - Header 2x1
Note:
If you have the one piece Finger Board with attached Communications board, you do not have to
install JP14. There are already pcb traces connecting JP14 to JP15.
You can omit JP6 and use the solder pads J1 and J2. By bridging solder pad J1, A/D ref input VRH
will be connected to VCC. Bridging solder pad J2 will connect A/D ref input VRL to ground. These two
pads are located on the bottom side of the board, near JP6.
Step 10
The following headers are normally installed on the bottom side of the Finger Board so that
prototyping boards can be used. Depending on your actual application, these headers can be placed
on top. Trim any excess lead lengths at this time before installing the headers.
JP4 - Header 4x2
JP7 - Header 8x2
JP9 - Header 10x2
JP11, JP8, JP17, JP16 - installed as one Header 12x2
Step 11
Install reset IC U1 and 5 volt regulator U2. Observe the silkscreened symbols on the PCB for proper
placement.
U1 - Dallas Semiconductor DS1233m (Note: DS1233 can be used, but its pins are different from the
DS1233m and will need to be oriented correctly)
We are currently replacing mc34064 with Dallas DS1233 from JDR Microdevices. We are still looking
for a source for the DS1233m, this is an equivalent part but has the same pin configuration as the
mc34064. The DS1233 is a far superior reset chip, we are very happy with the results and highly
recommend it over the mc34064. It will also reduce your parts count. If you are using the DS1233, you
will need to put the part in backwards and move the center pin to pin 1-square pad on the board. You
should also put a sleeve to prevent the wires from touching. (ie. pin1 now goes to pin 3 on the pcb
board, 2=>1, 3=>2). If you have the DS1233m, no changes are needed since it is a replacement for
the mc34064. We have provided a picture of this on our web page, under What's New.
U2 - LM7805
Note:
A low drop-out (LDO) voltage regulator can be substituted for the standard LM7805 regulator.
Applications that require low current use such as a solar cell powered Finger Board or running off 4
cell batteries may need a LDO regulator. If you install a LDO regulator, omit diode D2 and bridge
solder pad J4. The diode voltage drop will interfere with the LDO lowest voltage regulation. J4 is
located on the bottom side of the board, near JP1.
Step 12
Install crystal Y1. Cut a small piece of Mylar or thin cardboard insulation to prevent a short on the pc
board. Punch two small holes for the crystal leads so the insulator can fit against the bottom.
Y1 - 8Mhz crystal
