MAX7044

19-3221; Rev 0; 1/04 KIT ATION EVALU E L B A AVAIL www.DataSheet4U.com 300MHz to 450MHz High-Efficiency, Crystal-Based +13dBm ASK Transmitter General Description Features ♦ +2.1V to +3.6V Single-Supply Operation ♦ OOK/ASK Transmit Data Format ♦ Up to 100kbps Data Rate ♦ +13dBm Output Power into 50Ω Load ♦ Low 7.7mA (typ) Operating Supply Current* ♦ Uses Small, Low-Cost Crystal ♦ Small 3mm x 3mm 8-Pin SOT23 Package ♦ Fast-On Oscillator: 250µs Startup Time * At 50% duty cycle (315MHz, 2.7V supply, +13dBm output power) MAX7044 The MAX7044 crystal-referenced phase-locked-loop (PLL) VHF/UHF transmitter is designed to transmit OOK/ASK data in the 300MHz to 450MHz frequency range. The MAX7044 supports data rates up to 100kbps, and provides output power up to +13dBm into a 50Ω load while only drawing 7.7mA at 2.7V. 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 +2.1V to +3.6V. 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 ...