The ADL5570 from Analog Devices is a high-linearity power amplifier (PA) designed for mobile WiMAX terminals. The ADL5570 is optimized for operation in the 2.3-GHz to 2.4-GHz band and provides good performance across frequency bands from 2.5 GHz to 2.7 GHz. The device provides high levels of linearity, output power and efficiency to ensure seamless connectivity and reduce battery drain in portable devices.
High Levels of Linearity, Efficiency and Output Power
Battery life is a key consideration in the design of portable applications such as laptop computers, cellular handsets and PDAs. Compared to WiMAX PAs from other vendors, the ADL5570 consumes half the current and offers an industry-leading PAE (power-added efficiency) of more than 20 percent. This lower power consumption limits the need for heat sinks, increases system reliability and reduces size and cost. The exceptional output power of the ADL5570 is complemented by high linearity, which enables the higher data rates and increased signal propagation required for reliable WiMAX broadband connections. The output 1-dB compression point (P1dB) of 31 dBm allows the ADL5570 to operate in the linear region at output power levels of up to 26 dBm—at 3.5-V supply and 2.35 GHz—while maintaining an EVM (error vector magnitude) of less than three percent to minimize system-level signal noise. The combination of high output power, efficiency and signal fidelity provide users of WiMAX communications devices longer operation and fewer breaks in transmission, maximizing their mobile broadband experience. Additionally, the ADL5570 features a gain of 29 dB, which allows the device to be used with a wide variety of transceivers.
Additional Power Savings Modes
Operating with a single 3.2-V to 5.5-V supply, the ADL5570 consumes 250 mA RMS (root-mean-square). A low-power mode is also available for operation at levels less than 10 dBm, with optimized operating and quiescent currents of 100 mA and 70 mA, respectively. A standby mode is also available, which reduces the quiescent current to 10 mA and is useful when a time-division duplex terminal is receiving data.
Availability and Pricing
The ADL5570 is sampling now, with volume production scheduled for May 2007. Priced at $3.00 per unit in 10,000-piece quantities, it is available in a 16-pin 4 mm × 4 mm LFCSP (lead-frame chip-scale package). The device is specified over the extended industrial temperature range (–40 degrees C to +85 degrees C).