Rabbit RabbitCore RCM2200, User Manual

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User’s Manual 69
B.4.1 Adding Other Components
There is room on the Prototyping Board for a user-supplied RS-232 transceiver chip at
location U2 and a 10-pin header for serial interfacing to external devices at location J6. A
Maxim MAX232 transceiver is recommended. When adding the MAX232 transceiver at
position U2, you must also add 100 nF charge storage capacitors at positions C3–C7 as
shown in Figure B-7.
Figure B-7. Location for User-Supplied RS-232 Transceiver
and Charge Storage Capacitors on Back Side of Prototyping Board
NOTE: The board that is supplied with the DeviceMate Development Kit already has the
RS-232 chip and the storage capacitors installed, and is called the DeviceMate Demon-
stration Board.
There are two sets of pads that can be used for surface mount prototyping SOIC devices.
The silk screen layout separates the rows into six 16-pin devices (three on each side).
However, there are pads between the silk screen layouts giving the user two 52-pin (2×26)
SOIC layouts with 50 mil pin spacing. There are six sets of pads that can be used for 3- to
6-pin SOT23 packages. There are also 60 sets of pads that can be used for SMT resistors
and capacitors in an 0805 SMT package. Each component has every one of its pin pads
connected to a hole in which a 30 AWG wire can be soldered (standard wire wrap wire can
be soldered in for point-to-point wiring on the Prototyping Board). Because the traces are
very thin, carefully determine which set of holes is connected to which surface-mount pad.
There is also a space above the space for the RS-232 transceiver that can accommodate a
large surface-mounted SOIC component.
MAX232
100 nF
storage
capacitors
ry
ON