Complete 450MHz Quadrature Transmitter

The MAX2370 integrated quadrature transmitter is designed for 450MHz applications. The device takes a differential I/Q baseband input and converts it up to intermediate frequency (IF) through a quadrature modulator and IF variable-gain amplifier (VGA). The signal is then routed to an external IF filter and upconverted to RF through an image-reject mixer and RF VGA. The signal is further amplified with an on-chip power amplifier (PA) driver. An IF synthesizer, an RF synthesizer, a local oscillator buffer, and an SPI™/QSPI™/MICROWIRE™-compatible, 3-wire programmable bus complete the basic functional blocks of this IC.

The MAX2370 is available in a 48-pin TQFN package with exposed paddle and is specified for the extended temperature range (-40°C to +85°C).

Applications

* 450MHz CDMA/WCDMA Phones * OFDM, cdma2000®, WCDMA, NMT * Wireless Data Links

* 450MHz Operating Frequency

* +8dBm Output Power

* -64dBc Typical ACPR at ±885kHz Offset

* -66dBc Typical ACPR at ±1.125MHz Offset

* 100dB Power-Control Range

* Dual Synthesizer for RF and IF Local Oscillators

* SPI/QSPI/MICROWIRE-Compatible 3-Wire Interface Bus

* Single-Sideband Upconverter

* Directly Drives External Power Amplifier