MLX90109 Datasheet, PDF (8/9 Pages) List of Unclassifed Manufacturers – 125kHz RFID Integrated Transceiver

MLX90109
125kHz RFID Integrated Transceiver
Unique Features
Use of a parallel antenna offers multiple
advantages:
- maximum power efficiency.
- minimum system components
Ease of use thanks to:
- self resonating principle avoids zero
modulation
- flexible system configuration with higher Q's
- High level of integration.
A complete reader can be integrated on an ultra
small PCB thanks to:
- small body (150mills) SOIC8 package
- limited amount of external components
- Integrated decoding minimize demands on
microcontroller side.
Cross Reference
The MLX90109 can replace any integrated front-
end base station chip for read write operation to
125kHz transponders in the 125kHz range.
All competitive products are with serial antenna,
e.g. Marin p4092, or TEMIC U2270B.
Absolute Maximum Ratings
Supply Voltage, VDD (Overvoltage)
Storage Temperature Range, TS
ESD Sensitivity
VSS-0.3V to
VSS+6V
[-55, 125]°C
2kV
ESD Precautions
Electronic semiconductor products are sensitive
to Electro Static Discharge (ESD).
Always observe Electro Static Discharge control
procedures whenever handling semiconductor
products.
Disclaimer
Melexis reserves the right to periodically make
modifications to product specifications. The
information included herein is believed to be
accurate and reliable. However, Melexis
assumes no responsibility for its use; nor for
any infringements of patents or other rights of
third parties which may result from its use.
Melexis
FAQ
1. Since the MLX90109 under the specified
working conditions does not influence the
antenna resonance frequency, the spread
and temperature drift are determined by the
discrete antenna components only.
2. The same feature allows significantly
detuned transponders to change the
resonance frequency in case of good
coupling. This can be used to tune the
MLX90111 after assembly, to allow use of
high Q factors at minimum assembly cost.
3. Q = quality factor of the antenna reflects the
ratio between the stored electromagnetic
energy vs. the ohmic dissipated energy.
Without degrading Rpar:
Qreader = (2*pi*Fres*Lr)/Rr
Else Rr can often be neglected resulting in:
Qreader = Rpar*sqrt(Cr/Lr)
4. Zero Modulation
Due to mistuning of the resonance
frequency of transponder and reader
antennas compared to an external oscillator
frequency, the amplitude modulation
induced by the transponder on the reader
antenna is a mixture of amplitude and phase
modulation. At special combinations of the
three frequencies a pure phase modulation,
or zero (amplitude) modulation occurs.
Since the MLX90109 clock is extracted from
the antenna resonance frequency it is not
susceptible to this phenomenon.
5. The MLX90109 is insensitive to DC
magnetic levels.
6. Modudepth
=
(VPPmax+VPPmin)
(VPPmax-VPPmin)/
Glossary of Terms
1. Base station = reader IC + microcontroller
2. Transceiver = Write (Transmitter) and read
(receiver) unit
3. Q = antenna quality factor.
4. Modulation depth = ratio between the
antenna amplitudes that are used for
sending data with amplitude modulation.
MLX90109 Parallel Resonant transceiver
Page 8 of 9
Rev 1.4 19-Dec-00