Highest-performing audio op amp, claims TI

December 23, 2015 // By Graham Prophet
Citing lowest distortion and noise, high linear output current, and low power, Texas Instruments says its latest audio amplifier pushes the boundaries for professional and portable audio.

The OPA1622 is the newest addition to the company's Burr-Brown Audio line and is the next generation of the widely adopted OPA1612. The OPA1622 delivers high output power of up to 150 mW and extremely low distortion of -135 dB at 10 mW, enabling the highest performance for professional audio equipment. The OPA1622's small size, low power consumption and low distortion can deliver high-fidelity audio in portable devices such as headphone amplifiers, smartphones, tablets and USB audio digital-to-analogue converters (DACs).The OPA1622 op amp, TI adds;

- Pushes the boundaries of audio quality: Headphone amplifier designers can take advantage of its low total harmonic distortion (THD) of -135 dB at 10-mW output power into a 32-Ω load – a claimed 12 times better than the nearest competitor. It also delivers maximum output power of up to 150 mW before clipping while maintaining the lowest THD and noise (THD+N), providing a clean signal path for professional audio applications.

- Optimised for high-fidelity portable audio devices: Consumes quiescent current of 2.6 mA per channel and delivers high linear output current of 80 mA rms in a 3 x 3-mm dual flat no-lead (DFN) package. Increased power-supply rejection ratio (PSRR) of -97/-123 dB at 20 kHz enables low distortion from switching power supplies with no low-dropout regulator (LDO), saving board space without compromising audio performance.

- Unique pinout simplifies design and improves distortion performance: The OPA1622's ground-referenced enable pin is directly controllable from the low-power processor's general-purpose input/output (GPIO) pins without level-shifting circuits. Its pinout improves printed circuit board (PCB) layout and enables exceptional distortion performance at high output power.

- Eliminates audible clicks and pops: An enable-circuitry design limits output transients when the OPA1622 is transitioning into or out of shutdown mode.

A TINA-TI SPICE macromodel is available for the OPA1622 to help designers verify board-level signal-integrity requirements. A TI Designs – Precision reference design for voltage-output audio DACs will be available in