Maxim Integrated Products has released high-performing RF variable-gain amplifiers (VGAs) in monolithic form. Designed specifically for 2.5G/3G wireless-infrastructure applications, the MAX2056/MAX2057 deliver over 40 dB of linearly controlled dynamic range while maintaining up to 39 dBm of OIP3 and 64 dBm of OIP2 over all attenuation settings.

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The VGAs are tailored for 800 to 1000 MHz/1700 to 2500 MHz (respectively) WCDMA, GSM/DCS/PCS/EDGE, cdma2000, iDEN and WiMAX(s) wireless infrastructure applications. In these applications, high linearity and low noise figure are critical for maintaining high levels of ACLR and EVM transmitter performance. The MAX2056/MAX2057 also enhance receiver sensitivity and blocker immunity when they are used as IF VGAs within WiMAX and microwave terrestrial-link applications.

As complete SiGe VGAs, the amplifiers integrate two state-of-the-art, voltage-variable attenuators with a low-noise, high-linearity two-stage RF amplifier. The analog attenuators yield infinite control and high attenuation accuracy over selectable 22 dB or 44 dB control ranges. Cascading one attenuator of the MAX2056 low-band VGA with the on-chip amplifier yields 15.5 dB of gain, a noise figure of 4.5 dB, an OP1dB of 23.5 dBm, and an OIP3 level of 39 dBm. The MAX2057 high-band version similarly offers 15.5 dB of gain, a noise figure of 6 dB, an OP1dB of 23.8 dBm, and an OIP3 level of 37 dBm.

According to Maxim, because these amplifiers are monolithic solutions, significantly tighter gain and linearity spreads are realized over the closest competing GaAs multichip modules, or MCMs. When compared to the closest MCM competitor, the MAX2056/MAX2057 provide as much as 4 times less gain drift over -40°C to +85°C, 11 times better gain flatness over a 100 MHz bandwidth, 5 times less OIP3 degradation over the stated P-OUT range, and 10 times less OIP3 degradation over temperature, said the supplier. Each of these advantages translates directly into tighter system-level tolerances.

The MAX2056/MAX2057 come in pin-pin compatible, compact 6 mm x 6 mm, 36-pin thin QFN packages. Lead-free packaging is also available. Prices start at $5.96, in 1000-piece quantities.