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BOARD LAYOUT CONSIDERATIONS

If you are at all familiar with RF devices, you may be concerned about

specialized layout requirements. Fortunately, because of the care taken by

Linx in the layout of the module’s PCB, integrating a TR-XXX-SC-PA

transceiver into your design is very straightforward. By adhering carefully to a

few basic design and layout rules, you can enjoy a trouble-free path to RF

success.

Figure 8 shows the suggested PCB footprint for the TR-XXX-SC-PA.

A groundplane (as large as possible) should be placed directly under the TR-XXX-

SC-PA. This groundplane can also be critical to the performance of your antenna.

The SC-PA should, as much as reasonably possible, be isolated from all other

components on your PCB. Specifically, high-frequency circuitry such as crystal

oscillators should be kept as far away as possible from the module.

0.100" Typ.

1.3 "

50 mil pad w/

Groundplane on Lower Layer

Figure 8: Recommended PCB layout

POWER SUPPLY CONSIDERATIONS

The user must provide a clean source of power

to the module to ensure proper operation.

Power-supply noise will manifest itself as AM

and FM noise and can significantly affect

transceiver performance. Providing a clean

power supply for the module should be a high

design priority.

The TR-XXX-SC-PA incorporates an on-board

Low-Dropout Regulator allowing the module to

operate over an input voltage range of 2.7 to 13

volts DC. The module’s power-supply line should have bypass capacitors

configured as shown in figure 7. Actual capacitor values will vary depending on

noise conditions.

.1

µF

>22

µF

module

Figure 7: Suggested supply filter