APGRD001 Microchip Technology, APGRD001 Datasheet - Page 6

• Manufacturer Part Number: APGRD001
• Description: REF DESIGN PKE PIC16F639
• Manufacturer: Microchip Technology
• Type: PKE, RKEr

Specifications of APGRD001

• Frequency: 125kHz
• Processor To Be Evaluated: PIC16F639
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PIC16F639, PIC16F636, PIC18F2680
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

AN1024
FIGURE 5:
The antenna orientation problem can be significantly
reduced if the three antennas are placed orthogonally
on the same PCB board. This increases the probability
that at least one of the transponder antennas faces
toward the base station antenna at a given incident
during application. Figure 6 shows a graphical
illustration
transponder board. A large air-core coil is used for LCZ
and two ferrite-core coils are used for LCX and LCY.
There are companies that make the ferrite coils
specifically for the 125 kHz RFID and low-frequency
sensing applications.
DS01024B-page 6
Effective Antenna Surface Area = S cos a
a
of
Magnetic field from the base station
placing
ANTENNA ORIENTATION
DEPENDENCY
Transponder’s LF antenna
with surface area S
three
Line of axis
antennas
on
the
FIGURE 6:
Note 1: Keep the size of the air-core antenna (LCZ)
2: Keep the separation between the antennas
as large as possible, given the PCB space
available.
as far apart as possible to reduce a mutual
coupling between them.
Ferrite-core Antenna
Air-core Antenna
(LCX Input Pin)
(LCZ antenna)
Transponder PCB
Ferrite-core Antenna
RECOMMENDED ANTENNA
PLACEMENT ON
TRANSPONDER BOARD
(LCY Input Pin)
© 2007 Microchip Technology Inc.