MAX7057 300MHz to 450MHz

MAX7057 300MHz to 450MHz

MAX7057 300MHz to 450MHz ASK/FSK Transmitter Supports Multiple TI ple Opera TI ng frequencies with one crystal

The MAX7057 is a crystal-referenced phase-locked loop VHF/UHF transmitter designed to transmit TI ng ASK/FSK data over a wide frequency range.
The device supports any frequency from 300MHz to 450MHz using a single crystal reference and ensures that the output of the power amplifier remains matched to the antenna or load.
To achieve these advantages, the MAX7057 integrates a programmable frac TI onal-N PLL at the output of the power amplifier, as well as internal tuning capacitors that can be programmed to match the antenna or load.
The MAX7057 is ideal for power-sensitive applications such as home security systems, remote controls, and garage door openers.
Introduced the MAX7057 crystal-referenced, phase-locked loop (PLL) VHF/UHF transmitter for transmitting OOK/ASK/FSK data over a wide range of frequencies. The device can operate at any frequency in the 300MHz to 450MHz range with appropriate crystal frequencies and can transmit data at up to 100kbps NRZ (50kbps Manchester encoded).

To achieve this flexibility, the MAX7057 integrates a programmable fractional-N PLL synthesizer and a wideband VCO. Additionally, it has internal capacitors that can be programmed to match the imp eda that connects the power amplifier (PA) to the antenna. This topology ensures efficient transmission over multiple operating frequencies, making the MAX7057 ideal for power-sensitive applications such as home security systems, remote controls, and garage door openers.

To further improve performance, the MAX7057 integrates an envelope-shaping resistor between the PA output and the power supply. This resistor slows the on/off time of the PA in ASK mode, thereby reducing the spectral width of the PA modulated output signal.

The MAX7057's crystal-based architecture, eli mi, addresses many of the common problems with SAW transmitters by providing greater modulation depth, faster frequency settling, tighter transmit frequency tolerance, and reduced temperature dependence. Therefore, the device provides better overall receiver performance when using a superheterodyne receiver with a narrow IF (ie lower noise) bandwidth.

The MAX7057 operates from a single 2.1V-3.6V supply and draws less than 1µA in standby mode and less than 8.4mA in transmit mode. The device is available in a 16-lead SO package and is fully specified over the -40°C to +125°C automotive temperature range.