High-linearity dual mixers reduce power consumption, size for 4G MIMO Rx

High-linearity dual mixers reduce power consumption, size for 4G MIMO Rx

Suitable for MIMO and diversity wideband receivers, the LTC5590/1/2/3 family of high dynamic range dual downconverting mixers covers the 600-MHz to 4.5-GHz wireless infrastructure frequency range. The family offers an IIP3 of more than 26 dBm, low noise figures of less than 10 dB, and high conversion gain of 8.5 dB.

Unlike other dual mixers in their class, the LTC559x family can operate on a single 3.3-V supply, drawing a total supply current of 380 mA with both channels on. The LTC5590/1/2/3 consume 1.25/1.26/1.34/1.31 W, respectively — claimed to reduce power consumption by more than 24% compared to the closest competing solution.

Their low power consumption eases the thermal challenge associated with implementation of remote radio head, which can pack as many as 8 or 16 channels of receivers in weather-sealed housings. In addition, each channel of the LTC559x contains an integrated IF amplifier, LO buffer, and RF balun transformers on chip. Each mixer’s RF input is single ended, 50 Ω matched.

Each mixer can be independently shut down with a separate enable control. When disabled, the IC consumes a maximum of 500-µA standby current. In low-power mode, the IIP3 reduces from 26.2 dBm to a usable 21.4 dBm (at 1.95 GHz). Offered in a 24-lead 5 x 5-mm plastic QFN package, the parts are specified for a case operating temperature from –40° to 105°C. (LTC5591, $9.50 ea/1,000 — prod qty, LTC5591, available now; LTC5590, July; LTC5592, August; LTC5593, September.)

By Christina Nickolas

Linear Technology , Milpitas , CA
Sales Office 408-428-2050
www.linear.com