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RFID Circuits, Page 2
RFID Circuits:   #'s - N    M - Z

Last Updated on:
Thursday, April 07, 2016 01:01 PM


Circuits Designed by Dave Johnson, P.E.:

  • OPTICAL RFID TEST CIRCUIT
    I designed this test the concept of using light techniques to send identification data instead of RF. A more detailed discussion on this scheme can be found in the Imagineered new products section.
  • Wireless RFID Smart Key Detector
    Many cars now use a key with an imbedded RFID microchip.  The microchip is read when the key is inserted into the car’s ignition.  The keys containing a microchip often look the same as most other keys. People duplicating car keys will often not know of the microchip.  This circuit will light a LED if it detects a key containing a 125KHz RFID chip.

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Medium Power 125kHz Oscillator -  This circuit is similar to CMOS INVERTERS FORM 125KHZ OSCILLATOR but adds more inverters in parallel to deliver yet more power.  The values shown are for 125KHz.... [Designed by David A. Johnson]
Medium Power 125kHz Oscillator-2 -  This circuit is similar to MEDIUM POWER 125KHZ OSCILLATOR but adds even more inverters in parallel to deliver yet more power.  The values shown are for 125KHz.... [Designed by David A. Johnson]
Optical RFID Test Circuit -  I designed this test the concept of using light techniques to send identification data instead of RF. A more detailed discussion on this scheme can be found in the Imagineered new products section. …. [Designed by David A. Johnson]
Passive RFID Basics -  Microchip Application Note Published 13-Apr-99  (App Note - added 2/06)
RFID Coil Design -  Microchip Application Note Published 29-Sep-98  (App Note - added 2/06)
RFID Demokit 125kHz -  Transceiver including antenna for reading and writing, where possible, the 125kHz transponders EM4100, EM4102, EM4105, EM4150. Includes 2 tags each using the EM4150 and EM4100 and demonstration software. (added 3/05)
RFID Reader Handheld -  Intersil Application Block Diagram....[App Note - ]
RFID Smart Key Detector  -  Many cars now use a key with an imbedded RFID microchip.  The microchip is read when the key is inserted into the car’s ignition.  The keys containing a microchip often look the same as most other keys. People duplicating car keys will often not know of the microchip. This circuit will light a LED if it detects a key containing a 125KHz RFID chip. …. [Hobby Corner Circuit by Dave Johnson]
RFID Tag & COB Development Guide with Microchip's RFID Devices -  Microchip Application Note Published 21-Nov-02  (App Note - added 2/06)
RFID-Zapper -  Afraid the government is trying to track you? Want to disable your old credit cards wireless signal? Need to get that new backpack out of Macy’s without getting caught? You need to disable those RFID tags….(project added 6/07)
Transponder coils in an RFID system -  Coilcraft Power Magnetics Application Note (App Note - added 6/06)
Wideband RF ICs for Power Detection & Control -  DN335  Design Notes (Linear Technology) (App Note - added 1/06)
Wireless RFID Smart Key Detector  -  Many cars now use a key with an imbedded RFID microchip.  The microchip is read when the key is inserted into the car’s ignition.  The keys containing a microchip often look the same as most other keys. People duplicating car keys will often not know of the microchip. This circuit will light a LED if it detects a key containing a 125KHz RFID chip. …. [Hobby Corner Circuit by Dave Johnson]
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RFID Circuits:   #'s - N    M - Z


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