Wideband 15dB Gain Block Amplifier Launch, Low Noise Across 100kHz to 1.4GHz Range

Linear Technology Korea (CEO Hong Sa-kwak) has announced the launch of a wideband 15dB gain block amplifier (product name: LTC6433-15) that delivers outstanding linearity by providing 47dBm OIP3 (output third order intercept) and a noise figure of 3.22dB at 150MHz.

This amplifier offers outstanding OP1dB (output 1dB compression point) of 19.2dBm. The LTC6433-15 is completely different from other gain block amplifier products typically designed using GaAs or pHEMT processes. FET technology has a high 1/f noise corner in the 20MHz to 30MHz band, which can result in elevated noise floor. This means it cannot be used at lower frequencies.

In contrast, the LTC6433-15 amplifier core is designed using high-frequency SiGe bipolar technology. As a result, the amplifier's 1/f noise corner is much lower, typically below 10kHz. Therefore, with no significant noise rise, it can be used at low frequencies, even at 100kHz.

Additionally, the performance of GaAs and pHEMT type devices varies significantly depending on the internal FET bias voltage, and this variation can differ widely from device to device. However, the LTC6433-15 exhibits stable performance variation with temperature and between devices, and is not sensitive to power supply voltage variations.

The low-frequency performance of the LTC6433-15 expands the product's application scope and improves performance in a wide range of amplifier applications including cable network broadband signal sources, radar receiver IF amplifiers, VHF/UHF broadcast radio, and RF test instrumentation. The LTC6433-15 is an excellent product that can replace numerous operational amplifier solutions in amplifier applications that do not require DC coupling.

The LTC6433-15 input and output are matched to 50Ω wideband across the 100kHz to 1GHz range with 1dB flatness. This product has a –3dB bandwidth of 1.4GHz. The amplifier requires only input and output DC blocking capacitors, a choke to bias the open-collector output, and a feedback capacitor to set matching and gain flatness at low frequencies. Therefore, the LTC6433-15 simplifies wideband design and can be easily cascaded with minimal external components. The DC2168A evaluation board demonstrates this performance with flat gain, low noise, and industry-leading distortion performance covering the 100kHz to 1GHz band.

The LTC6433-15 operates from a single 5V power supply. This product consumes only 95mA of current. The device is designed to operate in a temperature range of –40°C to 85°C. The amplifier is available in a 4mm x 4mm plastic QFN package. Grade A products with guaranteed performance are priced at $4.98 per unit based on 1,000-unit quantities, while Grade B products are priced at $1.89 per unit. Both products are available for immediate purchase.