Triad Semiconductor Reimagines Audio Signal Capture With ‘Universal AFE’
The audio capture chip leverages Triad's current conveyor architecture to deliver a 156-dB input capture range from dual inputs.
Triad Semiconductor recently announced the TS5510, a two-channel analog front-end (AFE) low-noise programmable-gain input amplifier. The TS5510 audio capture device is designed for both home and professional recording applications.
The TS5510.
It can match both high- and low-level inputs to conventional analog-to-digital converters (ADCs) while preserving signal-to-noise ratio (SNR) and offering gain control flexibility. The new part replaces voltage-control with current-control amplification to dramatically expand the dynamic range possible between the two input channels.
Solving the High-Level/Low-Level Signal Challenge
Mixed device audio recording comes with a number of significant challenges, not the least of which is the variability in input signal levels. Microphones, instrument preamplifiers, synthesizer line outs, and other signals can have widely varying dynamic ranges, upper and lower limits, and base levels.
Typically, this requires signal preconditioning before sending it to the mixing board. High-level signals may require resistive pads or other attenuation devices. Low-level signals may require external pre-amplifiers. Each additional device introduces the possibility of distortion and common-mode noise, as well as additional expense.
The Multi-Signal Current Conveyor Innovation
The TS5510 mitigates the issue by utilizing the current conveyor-based architecture. Conventional input sections often utilize op amps, which are voltage amplifiers with voltage feedback. Op amps are subject to clipping at or near their limits. The current conveyor amplifier, in contrast, uses current feedback, allowing much greater bandwidth than a voltage-feedback amplifier. With digital control, the two inputs in each TS5510 can match widely diverse signal levels without external components.
Block diagram of the TS5510.
The current conveyor circuit was invented in 1968 but did not gain widespread use until recently, due to the widespread adoption of voltage-mode amplifiers. However, recent attention to the circuit has brought it into devices like the new TS5510.
Current conveyor circuits exhibit lower delay between input and output, a higher dynamic range, lower power consumption at high frequencies, and lower switching noise. In a voltage-controlled op amp, delay and slew distortion can be reduced by decreasing the voltage swing (reducing the gain), thereby decreasing the charging and discharging times. However, doing so can also decrease the signal-to-noise ratio. Current conveyor circuits have lower parasitic capacitance, so delay can be reduced without increasing noise. The end result is an amplifier with improved noise characteristics, a wider dynamic range, and greater flexibility in the amplification stage.
Key Features of the TS5510
The TS5510 accepts dual audio signals and matches them for delivery to an audio ADC. The amplifier features dual fully differential XLR signal paths with a total input capture range (TICR) of 156 dB, supporting signal levels from +28 dBU down to -128 dBU per AES-17. It offers a wide programmable gain range from -18 dB to +47 dB in precise 1-dB increments, along with a common-mode rejection ratio (CMRR) of greater than 90 dB for excellent noise performance.
Typical application diagram.
The device provides a balanced full-scale output drive of either 2 Vrms or 3 Vrms and is digitally controlled via SPI mode 0. Its highly integrated QFN form factor (7 mm x 7 mm) minimizes the need for external passive components, enabling a smaller overall PCB footprint.
The 156-dB TICR defines the difference between the smallest signal that it can resolve and the highest signal it can accept without clipping. Triad calls this “unprecedented dynamic range.” It is designed for direct coupling to any differential-input audio ADC to reduce system complexity.
Application and Availability
Triad designed the TS5510 to simplify audio mixers in both professional and home settings. It can also be applied in computer USB audio input devices, stage boxes, and audio routers.
The TS5510 EVK is a customer evaluation board (CEVB) that helps users bench-test the TS5510.
Triad Semiconductor offers an evaluation module, the TS5510 EVK. It has also made available a sample schematic diagram and a suggested PCB layout. The TS5510 is scheduled for production-level deliveries in March 2026.
All images used courtesy of Triad Semiconductor.