1 Features
• Ultra-low noise:
– Voltage noise: 2.9 nV/√Hz at 10 kHz
– Current noise: 6 fA/√Hz at 1 kHz
• Low distortion:
– 0.000029% (–131 dB) at 1 kHz
– 0.000035% (–129 dB) at 20 kHz
• High open-loop gain: 150 dB
• High output current: 100 mA
• Low input bias current: 10 pA
• Slew rate: 24 V/μs
• Gain bandwidth product: 53 MHz
• Rail-to-rail output
• Wide supply range:
±2.25 V to ±18 V or 4.5 V to 36 V
• Quiescent current: 3.9 mA per channel

2 Applications
• Professional microphones and wireless systems
• Professional audio mixer/control surface
• Guitar amplifier and other music instrument
amplifier
• A/V receiver
• Bookshelf stereo system
• Professional audio amplifier
• DJ equipment
• Turntable
• Special function module

3 Description
The OPA1655 and OPA1656 (OPA165x) are Burr-
Brown™ op amps designed specifically for audio
and industrial applications, where maintaining signal
fidelity is crucial. The FET-input architecture achieves
a low 2.9‑nV/√Hz voltage noise density and 6‑fA/√Hz
current noise density, allowing for very-low noise
performance in a wide variety of circuits. The high
bandwidth and high open-loop-gain design of the
OPA165x delivers a low distortion of 0.000035%
(–129 dB) at 20 kHz, and improves audio signal
fidelity across the full audio bandwidth. These devices
also feature excellent output current drive capability,
offering rail-to-rail output swing to within 250 mV of
the power supplies with a 2‑kΩ load, and can deliver
100 mA of output current.
The OPA165x operate over a very wide supply range
of ±2.25 V to ±18 V or (4.5 V to 36 V) on 3.9 mA
of supply current to accommodate the power-supply
constraints of many types of audio products. The
temperature range is specified from –40°C to +125°C.