This part is a kind of semiconductor called LT8900.
Function of this product has Low Cost 2.4GHz Radio Transceiver.
Manufacturers : ETC
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Some of the text within the PDF file :
LT8900 Datasheet Revision 1.2 LT8900 Low Cost 2.4GHz Radio Transceiver FEATURES z Complete 2.4 GHz radio transceiver includes fully integrated RF PLL and channel filtering z Supports Frequency-Hopping Spread Spectrum z Supports SPI and I2C bus interface z Built-in smart auto-acknowledge Tx/Rx protocol simplifies usage z Packet data rate 1 Mbps over-the-air z FIFO flag signal permits continuous streaming data at 1 Mbps over-the-air z Power management for minimizing current consumption z Digital readout of RSSI and temperature z Lead-free 4x4mm QFN Package & SOP16 for best RF performance GENERAL DESCRIPTION The LT8900 is a low-cost, fully integrated CMOS RF transceiver, GFSK data modem, and packet framer, optimized for use in the 2.4 GHz ISM band. It contains transmit, receive, RF synthesi [ ... ]