典型應用電路

The MAX2063 high-linearity, dual digital variable-gain amplifier (VGA) operates in the 50MHz to 1000MHz frequency range. Each digital attenuator is controlled as a slave peripheral using either the SPI?-compatible interface or a 5-bit parallel bus with 31dB total adjustment range in 1dB steps. An added feature allows “rapid-fire” gain selection between each of four steps, preprogrammed by the user through the SPI-compatible interface. A separate 2-pin control allows the user to quickly access any one of four customized attenuation states without reprogramming the SPI bus.

Since each of the stages has its own external RF input and RF output, this component can be configured to either optimize noise figure (amplifier configured first) or OIP3 (amplifier configured last). The device's performance features include 24dB of amplifier gain (amplifier only), 5.6dB noise figure (NF) at maximum gain (including attenuator insertion losses), and a high OIP3 level of +41dBm. Each of these features makes the device an ideal VGA for multipath receiver and transmitter applications.

In addition, the device operates from a single +5V supply with full performance, or a +3.3V supply for an enhanced power-savings mode with lower performance. This device is available in a compact 48-pin thin QFN package (7mm × 7mm) with an exposed pad. Electrical performance is guaranteed over the extended temperature range, from T_C = -40°C to +85°C.