Gain block amp delivers linearity with low noise

The LTC6433-15 – a wideband 15dB gain block amplifier delivering linearity of 47dBm OIP3 (output third order intercept) and 3.22dB noise figure at 150MHz – has been launched by Linear Technology.

The amplifier has an output 1dB compression point of 19.2dBm. The amplifier core is built using high frequency SiGe bipolar technology. As a result, the amplifier exhibits a low 1/f noise corner, typically less than 10kHz, making it usable at frequencies to 100kHz without significant noise rise. The LTC6433-15’s performance is stable over temperature and from device to device, and is insensitive to power supply voltage variations.

Applications include cable networks, broadband signal sources, radar receiver IF amplifiers, VHF/UHF broadcast radios and RF test instrumentation.

The LTC6433-15’s input and output are 50O wideband matched from 100kHz to 1GHz with 1dB flatness over that frequency range. It has a -3dB bandwidth of 1.4GHz. The amplifier needs an input and output DC blocking capacitor, plus a choke to bias its open collector output, and one feedback capacitor to set the matching and gain flatness at low frequencies. The DC2168A evaluation circuit covers the 100kHz to 1GHz band with flat gain, low noise and industry leading distortion performance.

The LTC6433-15 operates from a single 5V supply. It draws a nominal 95mA supply current. The device is specified for operation in temperatures ranging from -40 to 85°C. The amplifier is available in a 4 x 4mm plastic QFN package.