RF Transmitter-On-A-Chip Seeks FM Or FSK Modulated Apps

Integrating on a single chip all of the circuitry needed to implement a RF transmitter, the low-power TRF4900 IC is well-suited for use in portable, short-range wireless products, such as utility meters, security systems and electronic toys. This frequency hopping RF transmitter-on-a-chip is designed to work in the 850- to 950-MHz, industrial/scientific/medical (ISM) UHF band and can be used in either linear (FM) or digital (FSK) modulated applications. When used in datacomm apps, the IC supports transmission rates of 115 kbps (typ.). And with a tunable VCO, the chip allows a single design to be used in different parts of the world where different frequency bands have been set aside for ISM applications.
The transmitter chip also boasts of: a programmable direct digital synthesizer (DDS) that allows for fast frequency hopping; digital FSK modulation within the DDS, eliminating the need for external components here; hop-to-a-frequency times of just 30 µs; and support of both narrow- and wide-band operation. The TRF4900 requires a 2.2V-to-3.3V supply, has a low-power-dissipating sleep mode and fast wake-up time to active mode, and a serial port for interfacing to a wide range of processors. In 24-pin TSSOPs, TRF4900 costs $2.19 each/1,000.