The Texas Instruments LMX5252 Bluetooth Radio is a part of the third generation Bluetooth solution designed for use with short-range wireless applications.

The radio integrates a complete Bluetooth Class 2 transceiver, operating in the ISM frequency band (2.4-2.5 GHz). The modulation is Gaussian Frequency Shift Keying (GF- SK) with a Bluetooth product of 0.5 and a modulation index ranging from 0.28 to 0.35. Fast frequency hopping (1600 hops/s) is used over a total of 79 channels between 2.402 GHz up to 2.480 GHz. The channel bandwidth is 1 MHz.

The LMX5252 is designed in 0.18 µm RF CMOS technology for small die size and low power consumption. The LMX5252 is available in a 6.0 mm x 6.0 mm 36 pin thin quad flatpack no lead (WQFN) package.

• The LMX5252 provides a very compact radio solution for Bluetooth applications that put extra strong requirements on low cost and small form factors. In addition, the application benefits from very low signal loss between the antenna and the radio.
• The radio completely integrates the receiver and transmitter baluns, the antenna switch, and filter together with the voltage-controlled oscillator (VCO) tank on one single die. The fractional-N delta-sigma synthesizer and the crystal offer support for a wide range of external reference frequency clocks or crystals. The digital Received Signal Strength Indicator (RSSI) allows for efficient power control and communication with Bluetooth Class 2 devices. Several current saving modes are available.
• The baseband interface is completely digital and compatible with 8-pin bi-directional BlueRF using the RXMODE2 configuration. It can automatically adapt to the voltage levels used by different baseband controllers, independently of the supply voltage.