Programmable transceiver tackles Tyre-pressure monitoring

September 29, 2015 // By Graham Prophet
Melexis’ MLX73290-M is a multi-channel, low power RF transceiver IC addressing the sub-GHz ISM bands from 300 to 960 MHz: tit has two RF channels, each with a programmable RF PA and a sensitive RF receiver. It is fully programmable via its serial peripheral interface (SPI) and includes energy harvesting interface and transmit power detectors.

This IC is, according to Melexis (Tessenderlo, Belgium), suited to sub-GHz wireless applications such as home/building automation, tyre pressure monitoring (TPMS), automatic meter reading (AMR), alarm systems, passive keyless entry (PKE), medical diagnostics and telemetry. Its output power level ranges from -20 dBm to 13 dBm while its receiver sensitivity can attain -120 dBm in a 15 kHz bandwidth. With a maximum data rate of 250 kbps, the transceiver is also capable of handling heightened data throughputs. A wide variety of different RF parameters can be adjusted (number of channels, frequency resolution, output, frequency deviation, etc.), in order to satisfy specific application criteria. On-off keying (OOK), binary frequency shift keying (FSK), minimum shift keying (MSK), Gaussian minimum shift keying (GMSK) and Gaussian frequency shift keying (GFSK) modulation schemes are supported.

Two RF power detectors provide augmentation of radiated power performance during transmission. An energy harvesting interface allows battery-less power supply by using a solar cell in combination with a super capacitor. Evaluation boards and software tools are also available. In a 5 x 5 mm 32-lead QFN package, it operates over -40°C to 105°C.