1 Features
1• Gain Bandwidth: 20 MHz
• Low Noise: 8.5 nV√Hz at 1 kHz
• Slew Rate: 10 V/μs
• Low THD+N: 0.0005%
• Rail-to-Rail I/O
• Offset Voltage: 2 mV (maximum)
• Supply Voltage: 1.8 V to 5.5 V
• Supply Current: 1.5 mA/ch
– Shutdown: 0.1 μA/ch
• Unity-Gain Stable
• Small Packages:
– SOT-23, SON, VSSOP, TSSOP

2 Applications
• Sensor Signal Conditioning
• Consumer Audio
• Multi-Pole Active Filters
• Control-Loop Amplifiers
• Communications
• Security
• Scanners

3 Description
The OPAx322x series consists of single, dual, and
quad-channel CMOS operational amplifiers featuring
low noise and rail-to-rail inputs and outputs optimized
for low-power, single-supply applications. Specified
over a wide supply range of 1.8 V to 5.5 V, the low
quiescent current of only 1.5 mA per channel makes
these devices well-suited for power-sensitive
applications.
The combination of very low noise (8.5 nV√Hz at
1 kHz), high-gain bandwidth (20 MHz), and fast slew
rate (10 V/μs) make the OPAx322x family ideal for a
wide range of applications, including signal
conditioning and sensor amplification requiring high
gains. Featuring low THD+N, the OPAx322x series is
also excellent for consumer audio applications,
particularly for single-supply systems.
The OPAx322S models include a shutdown mode
that allow the amplifiers to be switched from normal
operation to a standby current that is typically less
than 0.1 μA.
The OPA322 (single version) is available in 5-pin
SOT-23 and 6-pin SOT-23, while the OPA2322 (dual
version) is offered in 8-pin VSSOP, 10-pin VSSOP, 8-
pin SOIC, and 8-pin SON packages. The quad
version OPA4322 comes in 14-pin TSSOP and 16-pin
TSSOP packages. All versions are specified for
operation from –40°C to +125°C.