AS3993-DK FERMI ams, AS3993-DK FERMI Datasheet - Page 14

• Manufacturer Part Number: AS3993-DK FERMI
• Description: RFID Transponder Tools AS3993 Demo Board Fermi
• Manufacturer: ams

Specifications of AS3993-DK FERMI

• Rohs: yes
• Product: RFID Readers
• Description/function: Demonstration Reader
• Frequency: 20 MHz
• Interface Type: SPI, USB
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Operating Supply Voltage: 5 V
• Tool Is For Evaluation Of: AS3993
• For Use With: AS3993 UHF RFID Reader IC

AS3993 – AN13 – Received Signal Strength Indicator (RSSI)
Balun Section:
Figure 10 - Schematic Balun Section
The output impedance of the 0 dBm (low power) outputs are 100 ohm differential. Therefore a
2:1 Balun is used to convert the RF track impedance to 50 ohm single ended. In case the ouput
power should be very low the resistor R8, R9 and R10 (Pi-Pad) can be used to attenuate the RF
signal. It would be also possible to reduce the output power via reader IC register settings but
this should be done only down to -6 dB as the local oscillator signal inside the IC would become
too low. Per default the Pi-Pad is not installed.
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Revision 2.0 / 6/22/12
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