SA7121A: 128 Bit Read-only Manchester Coded
Transponder
http://www.sames.co.za PRELIMINARY
FEATURES
§ EEPROM flexibility of data configuration
§ 128 bits of OTP data factory programmed and locked
§ Customer specific configuration of stored data
§ Data output in Manchester mode
§ Carrier frequency 100 to 300 kHz
§ On-chip resonance capacitor
§ No external charge storage capacitor required
§ On-chip full wave rectifier
§ On-chip data modulator
§ On-chip high voltage protection / regulation
§ On-chip RF frequency clock extractor / prescaler
§ Low power dissipation
DESCRIPTION
This device is manufactured in the SAMES 1.2µm N-well
EEPROM process. It has 128 bits, factory pre-programmed
and locked in EEPROM memory. Read data is Manchester
coded.
The device has an on-chip rectification circuit that converts
the incoming rf signal to DC power feeding V
DD
. There is
also an on-chip data modulator, which works in conjunction
with the rectifier. The time base is extracted by an on-chip
RF clock extractor. High voltage protection across the coil
inputs is provided internally. The energy is stored on
capacitance on chip due to low internal power consumption.
The device has an on-chip resonance capacitor connected
between the COIL1 and COIL2 pads. These features result
in a single external component count, comprised of, only the
coil.
Data is read at the RF interface by means of the on-chip
modulator. The stored bits are clocked out sequentially
during the read operation. An internal power-on reset is
provided which allows the device to start reading out data at
low voltages for improved tag range.
APPLICATIONS
§ Access Control
§ Industrial automation
§ Asset tracking
