3.4GHz to 3.8GHz SiGe Low-Noise Amplifier/PA Predriver

The MAX2645 is a versatile, high-linearity, low-noise amplifier designed for 3.4GHz to 3.8GHz wireless local loop (WLL), wireless broadband access, and digital microwave radio applications. The device features an externally adjustable bias control, set with a single resistor, that allows the user to meet minimum linearity requirements while minimizing current consumption. The amplifier's high-gain, low-noise performance and adjustable input third-order intercept (IP3) allow it to be used as a low-noise amplifier (LNA) in the receive path, a PA predriver in the transmit path, or as an LO buffer.

The MAX2645 features a logic-level gain control that provides a 25dB step reduction in gain, which improves IP3 performance for operation during high input signal level conditions. Supply current is reduced from 9mA in high-gain mode to 3mA in low-gain mode. The device also includes a logic-controlled shutdown mode, which reduces supply current to 0.1µA. The MAX2645 operates from a +3V to +5.5V supply and is offered in the miniature 10-pin µMAX® package (5mm x 3mm) with an exposed paddle. Its performance has been optimized for use with the MAX2683/MAX2684 3.5GHz SiGe mixers to provide a complete high-performance, front-end solution for 3.5GHz applications.

Applications

* Digital Microwave Radios * Wireless Broadband Access * Wireless Local Loop (WLL)

* 3.4GHz to 3.8GHz Frequency Range

* LNA Performance (High/Low-Gain Modes)

* Gain: +14.4dB/-9.7dB

* NF: 2.3dB/15.5dB

* Input IP3: +4dBm/+13dBm

* Supply Current: 9.2mA/2.7mA

* Highly Versatile Application

* Receive Path 1st and 2nd Stage LNA

* Transmit PA Predriver

* LO Buffer

* Adjustable IP3 and Supply Current

* 0.1µA Supply Current in Shutdown Mode

* +3.0V to +5.5V Single-Supply Operation

* 10-Pin µMAX-EP Package (5.0mm x 3.0mm)