User's Manual

Table Of Contents

MReX Transceiver User Manual v1.92 Firmware

OEM Integration

The use of the MReX as a module must obey the following OEM (Original Equipment Manufac-

turer) instructions in order to comply with FCC regulations.

Power Supply

The power supply circuit affects the RF compliance and must comply with the followings:

When connected to the “Power IN +” pin 12 of the MReX:

• VCC nominal voltage must be 5 to 9 Vdc

• VCC voltage drop during Tx slots must be lower than 100mV

• VCC voltage ripple during Tx in the supply pins must be minimized. High supply

voltage ripple values during RF transmissions directly affect the RF compliance.

• VCC under/overshoot at start/end of Tx slots should be absent or at least minimized.

When connected to the “Power IN + Battery (3V) “ pin 18 of the MReX:

• VCC nominal voltage must be 3Vdc

• VCC voltage drop during Tx slots must be lower than 100mV

• VCC under/overshoot at start/end of Tx slots should be absent or at least minimized.

Generic Digital Interfaces

When connecting inputs and outputs, documented connection guidelines in this manual must be fol-

lowed while considering specified electrical limits.

The MReX UART interface is a 3-wire (TX, RX and GND) 3.3V unbalanced asynchronous serial

interface, supporting:

• Device configuration,

• Data TX and RX, when operated as serial link,

• Firmware upgrades.

Antenna RF interfaces requirements

The MReX module must be connected to an antenna with an impedance of 50 Ohms, through the

SMA female connector. The antenna must not have a gain greater than 6dBi.