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Embedded Modules
© Tibbo Technology Inc.
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C1 and C2 capacitors: Do not use SMD capacitors -- use regular through-hole
aluminum capacitors. This really helps reduce noise produced by the power supply.
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This is an analog circuit, so layout matters. Apply reasonable "good layout" effort.
Ideally, one should use an oscilloscope to see what sort of "square wave" the
power supply generates, both at low and high input voltages, as well as light
and heavy loads. There are no recipes here -- just try and see what works for
your circuit.
Mechanical Dimensions
Notes:
Standard EM1000 devices do not have a wireless add-on connector (a.k.a. "SPI
port") and the "landing" PCB area for the connector is left empty (cross-section A).
Compatible wireless add-on modules (such as the
optionally be soldered into the connector pads (cross-section B).
Option "-A" EM1000 devices feature a 10-pin wireless add-on header (cross-section
C). The pins on this header are identical to all other pins of the EM1000 and face
the host PCB. This way the wireless add-on port of the EM1000 can be connected
to some other circuitry on the host PCB. For example, instead of mounting onto the
EM1000, the WA2000 can be mounted directly onto the host PCB. Option "-A"
EM1000 module is then required to facilitate the connection between the EM1000
and the WA2000.
Finally, option "-T" devices have a female wireless add-on port connector, which the
WA2000 can be plugged into. EM1000 modules of "-T" variety (cross-section D) are
intended for convenient testing of the WA2000 and are not recommended for use in
production devices.