ib technology

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Micro RWD MF (Mifare) LP (low-power) specification

The MicroRWD MF (Mifare) LOW-POWER version is a complete read/write system for

13.56 MHz Mifare 1k, 4k and Ultralight cards. The module is pin-compatible and virtually

identical in operation and features to the “standard” version (NOTE differences in EEPROM

parameters and the three polling rates).

However the LOW-POWER version uses a different specification microcontroller offering

lower voltage operation and is designed to be powered from four alkaline battery cells.

During the Polling Delay period the microcontroller enters SLEEP mode with the RF device

in hard power-down mode to reduce the current consumption to a very low level.

The module wakes up after the polling delay period and the process repeats. The RWD-

MIFARE “low-power” Windows applications can be used to configure the parameters and

read/write data.

Parameter

Typical Value

Supply Voltage (performance optimised for 5 volt operation)

4 – 6 volts DC (operation

from 4 x alkaline cells)

Operating temperature

-40 deg C to + 85 deg C

AVERAGE current consumption. (1 second polling)

Less than 150 µ

µ

µ

µA

Active period for RF AND host communication (each

polling cycle).

Up to 20 mS

Peak antenna voltage (optimum tuning)

30 volts peak-to-peak

Peak antenna current (optimum tuning) for short period each

polling cycle (up to 10 mS burst)

150 mA

Polling Delay (SLEEP / Power-down mode)

4 mS to 8 seconds

Current consumption during Polling delay / SLEEP

Less than 20 µA

Current consumption during RF ON each polling cycle

Less than 20mA

Maximum data rate (between card and RWD)

106k baud

Range (dependent on antenna dimensions and tuning)

25-50 mm

Auxiliary output drives

Up to 25mA

Serial Interface

TTL level RS232

Serial Communication Parameters

9600 baud, 8 data bits, no

parity, 1 stop bit protocol

with CTS handshake

Basic electrical specification with LEDs pins and auxiliary outputs NOT connected.

Note that the MicroRWD MF (Mifare) LOW-POWER version is designed for optimum

performance and range at 5-volt operation. Performance will be reduced at maximum and

minimum operating voltage.

During the “Polling Delay” SLEEP/Power-down period the logic levels on the RWD pins

remain active and so for minimum current consumption, the LEDs and the auxiliary output

drives must be disconnected (and the Beep output delay set to zero).