MAX7044, Crystal-Based, ASK Transmitter

Analog Devices' MAX7044, crystal-referenced, phase-locked-loop (PLL), VHF/UHF transmitter is designed to transmit OOK/ASK data in the 300 MHz to 450 MHz frequency range. The MAX7044 supports data rates up to 100 kbps, and provides output power up to 13 dBm into a 50 Ω load while only drawing 7.7 mA at 2.7 V.

The crystal-based architecture of the MAX7044 eliminates many of the common problems with SAW-based transmitters by providing greater modulation depth, faster frequency settling, higher tolerance of the transmit frequency, and reduced temperature dependence. The MAX7044 also features a low supply voltage of 2.1 V to 3.6 V. These improvements enable better overall receiver performance when using the MAX7044 together with a superheterodyne receiver such as the MAX1470 or MAX1473.

A simple, single-input data interface and a buffered clock-out signal at 1/16th the crystal frequency make the MAX7044 compatible with almost any microcontroller or code-hopping generator. The MAX7044 is available in an 8-pin, SOT23 package and is specified over the -40°C to 125°C automotive temperature range.