ATSAM4S-WPIR-RD Atmel, ATSAM4S-WPIR-RD Datasheet - Page 19

• Manufacturer Part Number: ATSAM4S-WPIR-RD
• Description: Development Boards & Kits - ARM SAM4S16 W.PIR CAMERA REF. DESIGN
• Manufacturer: Atmel

Specifications of ATSAM4S-WPIR-RD

• Rohs: yes
• Product: Reference Designs
• Tool Is For Evaluation Of: ATSAM3S4BA
• Core: ARM Cortex M3
• Interface Type: JTAG, USB
• Operating Supply Voltage: 5 V
• Data Bus Width: 32 bit
• For Use With: RF231USB-RD

5.
PCB layout description
This chapter describes critical layout details to be carefully considered during a PCB design. The PCB design requires
an optimal solution for the following topics:
The RF231USB is a four-layer FR04-PCB with a thickness of 1.0mm. All layers are used as ground planes, except
midlayer two, which is used as supply voltage plane.
Figure 5-1. PCB layer stack.
The RF section layout is shown in
RF transceiver (1), the 16MHz crystal routing (2), the ground plane routing, feed line design (3), the ceramic antenna (4)
with matching network (5) and finally the coaxial connector for test measurements (6).
Each of them is described in detail in one of the following sections.
Mid 1
Mid 2
Bottom
•
•
•
•
Create a solid ground plane for the antenna. The PCB has to be considered as a part of the antenna; it
interacts with the radiated electromagnetic wave
Isolate digital noise from the antenna and the radio transceiver to achieve optimum range and RF performance
Isolate digital noise from the 16.000MHz reference crystal to achieve optimum transmitter and receiver
performance
Reduce any kind of spurious emissions below the limits set by the individual regulatory organizations
Atmel AVR2030: ATRF231USB – Hardware User Manual [APPLICATION NOTE]
Figure 5-2
where critical sections are marked by numbers: the RF pin fan out of the
380μm
100μm
380μm
Figure 5-1
shows its layer stack:
42018A−AVR−08/2012
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