25 July 1996
23 mm Transponder Reference Manual
Page 5 of 22
2. Transponder Packaging
The dimensions of the transponder are given in Figure 3.
The 23 mm shape offers several advantages:
1. The transponder is hermetically sealed.
2. The transponder is robustly constructed to withstand vibration (IEC68-2-6) and shock
(IEC68-2-6).
3. For Applications where read range is not the most critical point the transponder can be
mounted or used in such a way that the orientation is not controlled.
Figure 3: Dimensions of the TIRIS 23 mm Transponder (in mm)
3. Product Codes
64 bit Read Only device:
RI-TRP-RRHP
64 bit Read/Write device:
RI-TRP-WRHP
4. Function
The Pulsed FM System uses a sequential function principle separating the transponder powering
(charge) and transponder data transmission mode. The advantages of the sequential mode are
described in Section 5.1 "Basic System Data".
4.1 Read (Reading of RO and R/W Transponders)
During the charge (or powering phase) of between 15 and 50 ms the interrogator generates an
electromagnetic field using a frequency of 134.2 kHz. The resonant circuit of the transponder is
energized and the induced voltage is rectified by the integrated circuit to charge the capacitor.
The transponder detects the end of the charge burst and transmits its data using Frequency Shift
Keying (FSK), utilizing the energy stored in the capacitor.
