-140

-120

-100

-80

-60

0.00001

0.0001

0.001

0.01

0.1

10

100

1k

10k

Frequency (Hz)

Gain = 10 V/V

Gain = 1 V/V

Gain = -1 V/V

C002

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An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.

OPA1678, OPA1679

SBOS855A – FEBRUARY 2017 – REVISED MAY 2018

OPA167x Low-Distortion Audio Operational Amplifiers

1

1 Features

1

•

Low Noise: 4.5 nV/

√Hz at 1 kHz

•

Low Distortion: 0.0001% at 1 kHz

•

High Open-Loop Gain: 114dB

•

High Common-Mode Rejection: 110 dB

•

Low Quiescent Current:

–

2 mA Per Channel

•

Low Input Bias Current: 10 pA (Typical)

•

Slew Rate: 9 V/μs

•

Wide Gain Bandwidth: 16 MHz (G = 1)

•

Unity-Gain Stable

•

Rail-to-Rail Output

•

Wide Supply Range:

–

±2.25 V to ±18 V, or 4.5 V to 36 V

•

Dual-Channel and Quad-Channel Versions

•

Small Package Sizes:

–

Dual-Channel: SO-8, MSOP-8, SON-8

–

Quad-Channel: SO-14, TSSOP-14, QFN-16

2 Applications

•

Analog Signal Conditioning

•

Analog and Digital Mixers

•

Audio Effects Pedals

•

A/V Receivers

•

Car Audio Systems

3 Description

The OPA1678 (dual-channel) and OPA1679 (quad-

channel) operational amplifiers offer higher system-

level performance over legacy op amps commonly

used in audio circuitry. The OPA167x amplifiers

achieve a low 4.5-nV/

√Hz noise density and low

distortion of 0.0001% at 1 kHz which improves audio

signal fidelity. They also offer rail-to-rail output swing

to within 800 mV with a 2-kΩ load, which increases

headroom and maximizes dynamic range.

The OPA1678 and OPA1679 operate over a very

wide supply range of ±2.25 V to ±18 V or (4.5 V to 36

V) on only 2 mA of supply current to accommodate

the power supply constraints of many types of audio

products. These op amps are unity-gain stable and

provide excellent dynamic behavior over a wide range

of load conditions allowing them to be used in many

audio circuits.

The OPA167x amplifiers use completely independent

internal circuitry for lowest crosstalk and freedom

from interactions between channels, even when

overdriven or overloaded.

The OPA167x temperature ranges are specified from

–40°C to +85°C.

Device Information(1)

PART NUMBER

PACKAGE

BODY SIZE (NOM)

OPA1678

SOIC (8)

4.90 mm × 3.91 mm

VSSOP (8)

3.00 mm × 3.00 mm

SON (8)

3.00 mm × 3.00 mm

OPA1679

SOIC (14)

8.65 mm × 3.91 mm

TSSOP (14)

5.00 mm × 4.40 mm

(1) For all available packages, see the orderable addendum at

the end of the data sheet.

Simplified Internal Schematic

THD+N vs Frequency (2-kΩ Load)