Buffer amplifier increases signal bandwidth by 10×

Texas Instruments Inc. (TI) has claimed the industry’s widest-bandwidth high-input-impedance (Hi-Z) buffer amplifier that can support frequency bandwidths up to 3 GHz. Reporting a 10× increase in signal bandwidth in data-acquisition systems, the wider bandwidth and high slew rates of the BUF802 enable higher signal throughput and minimal input settling time. This enables designers to measure higher-frequency signals more accurately in test and measurement applications including oscilloscopes, active probes and high-frequency data-acquisition systems, said TI.

The bandwidth achieved by the BUF802 was previously only possible by using application-specific integrated circuits (ASICs), said TI. By eliminating the ASICs and simplifying the front-end designs by using the BUF802, designers can achieve a wide dynamic range “at a fraction of the cost,” said the company.

In addition, previous alternatives to ASIC-based design implementations required dozens of discrete components such as field-effect transistors (FETs), protection diodes and transistors, which added cost and system complexity and did not deliver the same bandwidth of ASICs, said TI.

Click for a larger image. (Source: Texas Instruments Inc.)

The BUF802 is called a single-chip alternative to ASICs or FET-input amplifier-based implementations. TI said the new solution integrates the features of discrete components and provides 10 times wider bandwidth than FET-input amplifiers, matching the performance of custom ASICs.

The BUF802 is reportedly the industry’s first buffer to enable quiescent current adjustment for a wide range of bandwidth and signal swing requirements, from 100 MHz to 3 GHz at 1-V peak to peak (VPP) and as high as 2 GHz at 2 VPP. This enables designers to scale their front-end designs across multiple data-acquisition applications.

In addition, the BUF802 can be used as a standalone buffer or in a composite loop with a precision amplifier like the OPA140 thanks to the integrated functional modes.

“As a stand-alone buffer, the BUF802 can help achieve high input impedance and high slew rates in applications that can tolerate 100-mV offsets or where the signal chain is AC-coupled,” said TI. “In a composite loop, the new buffer can achieve high DC precision and 3-GHz bandwidth in applications requiring 1 μV/°C maximum offset drift.”

TI BUF802 schematic (CL mode). Click for a larger image. (Source: Texas Instruments Inc.)

The BUF802, housed in a 3 × 3-mm, 16-pin VQFN package, is available for purchase on TI.com and is priced at $1.80 in quantities of 1,000. The BUF802RGTEVM evaluation module is available on TI.com for $25. Click here for additional resources and the reference design “Flexible 3.2-GSPS multi-channel AFE reference design for DSOs, radar and 5G wireless test systems.”