300MHz to 450MHz Low-Power, Crystal-Based +10dBm ASK/FSK Transmitter

The MAX1479 crystal-referenced phase-locked-loop (PLL) VHF/UHF transmitter is designed to transmit ASK, OOK, and FSK data in the 300MHz to 450MHz frequency range. The MAX1479 supports data rates up to 100kbps in ASK mode and 20kbps in FSK mode (both Manchester coded). The device provides an adjustable output power of more than +10dBm into a 50Ω load. The crystal-based architecture of the MAX1479 eliminates many of the common problems of SAW-based transmitters by providing greater modulation depth, faster frequency settling, higher tolerance of the transmit frequency, and reduced temperature dependence. These improvements enable better overall receiver performance when using the MAX1479 together with a superheterodyne receiver such as the MAX1470, MAX1471, MAX1473, or MAX7033.

The MAX1479 is available in a 16-pin TQFN package (3mm x 3mm) and is specified for the automotive temperature range from -40°C to +125°C.

Applications

* Garage Door Openers * Radio-Controlled Toys * Remote Keyless Entry (RKE) * RF Remote Controls * Security Systems * Tire-Pressure Monitoring (TPM) * Wireless Computer Peripherals * Wireless Game Consoles * Wireless Sensors

* ETSI-Compliant EN300 220

* +2.1V to +3.6V Single-Supply Operation

* Supports ASK, OOK, and FSK Modulations

* Adjustable FSK Shift

* +10dBm Output Power into 50Ω Load

* Low Supply Current (6.7mA in ASK Mode, and 10.5mA in FSK Mode)

* Uses Small Low-Cost Crystal

* Small 16-Pin TQFN Package

* Fast-On Oscillator—200µs Startup Time

* Programmable Clock Output