The OPAx323 family of op amps includes single / dual / quad channel (OPA323, OPA2323, OPA4323), ultra low-voltage (1.7V to 5.5V), high-bandwidth (20MHz) amplifiers. This family of amplifiers feature a zero-crossover input stage and a rail-to-rail output stage that can be used for variety of applications across industrial and automotive markets. The input common-mode voltage range includes signal swing beyond the supply rails, and allows the OPAx323 to be used in many single-supply or dual supply configurations. Rail-to-rail output swing significantly increases dynamic range, especially in low-supply applications with the class AB output stage capable of driving smaller resistive loads.

The OPAx323 family of zero-cross input stage amplifiers achieve high linearity for input signals with rail-to-rail swing that are typical in ADC driver applications in comparison to the complementary input stage amplifiers. Gain-bandwidth of 20MHz helps provide a fast settling response for ADC sampling speeds between 0.5 to 5MSPS depending on the settling performance required. The OPAx323 easily supports precision performance in high gain voltage sensing applications (such as the wheatsone bridge), as the device features maximum offset of 1.25mV and drift of 1.8μV/°C. This unique combination of high precision and high gain-bandwidth enables use in multiple applications such as the motor rotary encoders, microphone audio pre-amplifiers and ultrasonic transducers.

The OPAx323 family consumes only 1.6mA supply current per channel for 20MHz gain bandwidth, thus providing a good AC performance at a very low power consumption. These devices achieve a high slew-rate of 33V/μs allowing for fast detection of faults in motor current sensing applications. The zero-cross over input stage provides identical AC and DC performance for both low and high-side sensing applications, thus making the OPAx323 the best choice for current sensing in a variety of end equipments such as the solar string inverters, power delivery, grid, and EV infrastructure. Precision transimpedance and voltage gain applications are well served with a low input bias current (0.5pA typical, 20pA maximum), a good PSRR (20μV/V maximum), CMRR (100dB minimum), and A_OL (114dB minimum). The device has 60° of typical phase margin with no load and drives up to 75pF with a phase margin of 35°.

The OPAx323 has an internal current limit that enables additional robustness when operating with high output current while driving smaller output impedance like 68Ω, 128Ω, and 256Ω loads in audio applications. The OPAx323 can swing very close to the rails and has a short circuit current of ±80mA minimum at 5.5V power supply. The OPAx323S devices provide shutdown functionality for additional power savings and help disable the amplifier when idle. These op amps feature an integrated radio frequency immunity (RFI) and electro-magnetic interference (EMI) rejection filter, unity-gain stability, and no-phase reversal in input overdrive conditions.