5-GHz Differential Amp Solves The Drive Problem

Jun 15, 2010 11:22 AM, Louis E. Frenzel, Editor in Chief

Every modern digital wireless device begins with a fast analog-to-digital converter (ADC). But the performance of that ADC depends on the input circuits, which include amplifiers, matching circuits, and protection. Get these wrong, and everything else is compromised. Analog Devices solves this problem with the ADA4960-1.

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This 5-GHz differential amplifier drives ADCs with signals from dc to 1 GHz. This high-performance, low-distortion, ultra-high-speed device is designed for driving a wide variety of high-speed ADCs with 10-bit linearity to 500 MHz and 8-bit linearity up to 1 GHz. For example, it’s a good fit with the Analog Devices AD9626 12-bit ADC and AC9211 10-bit ADC.

The ADA4960-1 consumes just 60 mA of quiescent current when operating up to 1 GHz. It features a 7000-V/µs slew rate (AV = 6 dB, 2-V p-p output) and wideband, low-distortion performance for frequencies up to and beyond 1 GHz, making it effective for radio-frequency and immediate-frequency wired communications applications in industrial and instrumentation, defense electronics, and aerospace designs.

With its gain-adjust and bandwidth extension features, the ADA4960-1 can be configured for line driver and channel equalization applications. The amplifier also offers –3-dB bandwidth of 5 GHz (AV = 6 dB), single-resistor programmable gain of 0 to 18 dB, differential or single-ended input to differential output, and a fast settling time of 1 ns to 1% and overdrive recovery of 10 ns.

Furthermore, the ADA4960-1 boasts 5-V single-supply operation and 0.1 gain flatness to 300 MHz. Its low harmonic distortion (HD2/HD3 at AV = 6 dB) is –88/–69 dBc at 250 MHz, –77/–66 dBc at 500 MHz, –73/–72 dBc at 1 GHz, and –63 dBc IMD3 at 1 GHz. The ADA4960-1 can operate from –40°C to 105°C as well.