RFID Tag - Credit Card Datasheet

1023_1_Product_Manual created: 10/12/07 Page 9
Multiple Tags
The PhidgetRFID offers no capability for collision detection or collision avoidance. If two tags
are brought within the read field of a PhidgetRFID reader at the same time, neither tag will be
read. An RFID tag should be removed from the read field before a second tag is introduced.
Controlled Outputs
The PhidgetRFID has four outputs - two of which are available to the user, and two of which
are for internal control of the Phidget board only.
Output 0 is a +5V source from the USB bus through a P-Channel MOSFET with less than one
ohm impedance. This can be used to switch a TTL or CMOS device, or it can be used to drive
a 5VDC relay such as the Aromat JS1-5V. Output 1 is an LED drive output at 5VDC with
approximately 20mA of available current (250 ohm CMOS output). Both Output 0 and 1 are
available in hardware at the terminal blocks on the PhidgetRFID board. If Output 0 is used to
drive a relay, a fast clamping diode must be placed across the relay drive pins as shown in the
diagram below. Not doing so can result in permanent damage to the PhidgetRFID board.
The PhidgetRFID comes equipped with an on-board LED that can be controlled using the
LED property in software. Additionally, the on-board antenna can be enabled or disabled in
software by using the RF Enable property. The antenna must be enabled for the PhidgetRFID
to detect and read an RFID tag.
Output Function Connection
0 +5VDC Source Terminal Block
1 External LED Drive Terminal Block
LED Internal LED Drive Internal Only
RF Enable RF Antenna Enable Internal Only
5VDC RELAY
PhidgetRFID
5V
G