Texas Instruments VCA2612Y/2KG4

Overview

VCA2612Y/2KG4 from Texas Instruments is a dual-channel, highly integrated variable gain amplifier subsystem comprising a low-noise preamplifier (LNP) and a voltage-controlled attenuator/programmable gain amplifier (VCA/PGA) per channel. It delivers 1.25nV/√Hz input-referred noise at 25dB LNP gain, 40MHz VCA bandwidth, differential I/O, and 24dB–45dB programmable VGA gain - optimized for ultrasound front-ends requiring high dynamic range and low crosstalk.

For engineers reviewing the VCA2612Y/2KG4 datasheet, VCA2612Y/2KG4 pinout, VCA2612Y/2KG4 application, or VCA2612Y/2KG4 equivalent, key selection criteria include its dual-channel active termination capability, 52dB crosstalk at 5MHz, analog gain control interface (0.2V–3.0V), TQFP-48 package compatibility, and support for both differential and single-ended signal paths in medical imaging and test equipment signal chains.

Technical Context

The VCA2612Y/2KG4 implements a cascaded architecture: each channel integrates an LNP with switchable active termination (via FB/SWFB pins), followed by a VCA stage controlled by VCACNTL and MGS bits, then a digitally programmable PGA. The LNP provides four strappable gains (5/17/22/25dB) and accepts single-ended or differential inputs while generating differential outputs.

The VCA section uses shunt-connected FETs modulated by VCACNTL to achieve dB-linear attenuation (0–45dB), while the PGA's gain range (24–45dB) is selected via three MGS bits (pins 40–42). Both channels share a common VCA control voltage and internal reference (VCM = 2.5V), enabling matched gain tracking and low interchannel crosstalk (68dB typical).

Key Specifications

Pinout & Package

TQFP-48 package with exposed thermal pad; 7mm × 7mm footprint, 0.5mm pitch, RoHS-compliant lead finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar variable gain amplifier applications.

Compared with VCA2612Y/2KG4, the VCA2615Y/2K offers identical per-channel performance in a smaller footprint but sacrifices channel-to-channel matching required for beamforming, while the LMH6514MA/NOPB trades 3.25× higher input noise for 17.5× greater bandwidth - making VCA2612Y/2KG4 uniquely suited for precision medical and test instrumentation demanding ultra-low noise and dual-channel coherence.

Availability

VCA2612Y/2KG4 is available at Aetrix Electronics and suitable for ultrasound systems, wireless receivers, and high-fidelity test equipment requiring stable component supply, consistent parametric performance across production lots, and long-term lifecycle support.

Supply support for VCA2612Y/2KG4 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with over 50 years of innovation in precision signal chain components.

The VCA2612Y/2KG4 belongs to TI's high-performance analog front-end product line, designed specifically for medical ultrasound, communications infrastructure, and automated test equipment where low-noise amplification, programmable gain, and channel matching are critical.

FAQ

What is the maximum differential output swing supported by the VCA2612Y/2KG4?

The VCA2612Y/2KG4 supports a 2VPP differential output swing from the LNP stage and a 2VPP differential output from the VCA/PGA stage when driving ≥500Ω loads per side to ground. This swing is maintained across the full 24dB–45dB gain range and enables direct interfacing with high-performance ADCs such as TI's ADS5500 series without additional buffering.

How does active termination reduce noise figure in the VCA2612Y/2KG4 LNP?

Active termination in the VCA2612Y/2KG4 LNP replaces passive shunt termination with a feedback network that avoids signal current loss in the termination resistor. This technique improves noise figure by up to 4.6dB compared to conventional 75Ω shunt termination, as confirmed in TI's SBOS117C datasheet under "Active Feedback With the LNP" section.

Can the VCA2612Y/2KG4 operate with single-ended inputs and outputs?

Yes, the VCA2612Y/2KG4 supports both differential and single-ended configurations. The LNP accepts single-ended inputs (e.g., from coaxial transducer cables), and the VCA output can be used in single-ended mode by terminating one side to ground - though this incurs a 6dB signal amplitude reduction versus differential operation, as documented in the Electrical Characteristics table.

What is the purpose of the MGS1–MGS3 pins on the VCA2612Y/2KG4?

The MGS1–MGS3 pins (pins 40–42) are digital inputs that select the maximum gain ceiling of the PGA stage: 24dB, 27dB, 30dB, 33dB, 36dB, 39dB, 42dB, or 45dB. These bits define the upper bound of the swept-gain curve and are latched on power-up; they must be held static during operation to maintain gain stability across both channels of the VCA2612Y/2KG4.

Does the VCA2612Y/2KG4 include internal power supply regulation?

Yes, the VCA2612Y/2KG4 integrates an internal reference circuit (VCM = 2.5V, pin 19) supplied from VDDR, which regulates critical bias points and reduces sensitivity to power supply ripple. Separate VDDA/VDDB supplies and GNDA/GNDB grounds further isolate analog domains, contributing to the device's 68dB crosstalk performance and PSRR >45dB up to 1MHz.