The OPA2333 is a dual, ultra-low power, precision zero-drift CMOS operational amplifier utilizing proprietary auto-calibration technology. It provides near-zero offset voltage and drift over time and temperature, alongside rail-to-rail input and output (RRIO) performance. Operating on a micro-power quiescent current of just 17µA per channel, the OPA2333 is ideal for high-precision, low-power portable instrumentation, battery-powered medical equipment, and precise sensor signal conditioning.

Specifications

• Brand / Manufacturer: Texas Instruments
• Part Number: OPA2333 / OPA2333AIDGKR / OPA2333AIDGKT
• Amplifier Type: Zero-Drift Dual Operational Amplifier
• Supply Voltage Range: 1.8V to 5.5V (Single Supply) or ±0.9V to ±2.75V (Dual Supply)
• Low Offset Voltage: 10µV (Maximum at 25°C)
• Offset Voltage Drift: 0.05µV/°C (Maximum)
• Quiescent Current: 17µA per channel (Typical)
• Gain Bandwidth Product (GBW): 350 kHz
• Slew Rate: 0.16 V/µs
• Input Bias Current: 70 pA (Typical)
• Common-Mode Rejection Ratio (CMRR): 130 dB (Typical)
• Power-Supply Rejection Ratio (PSRR): 130 dB (Typical)
• Input / Output Configuration: Rail-to-Rail Input and Rail-to-Rail Output (RRIO)
• Operating Temperature Range: -40°C to +125°C
• Package / Case: MSOP-8 (VSSOP-8) Surface Mount

Features

• Zero-Drift Architecture: Employs continuous auto-zero calibration to virtually eliminate offset voltage and 1/f (flicker) noise, delivering exceptional DC accuracy.
• Micro-Power Operation: Consumes only 17µA of supply current per amplifier, significantly extending battery life in energy-sensitive applications.
• Rail-to-Rail Input & Output: Allows input signals to swing 100mV beyond the power supply rails and maximizes output dynamic range across low-voltage supplies.
• Low 1.8V Operation: Fully specified and operational down to 1.8V, making it fully compatible with low-voltage single-cell and multi-cell battery systems.
• High Precision DC Performance: Outstanding CMRR and PSRR ratings of 130 dB minimize errors introduced by power supply fluctuations and common-mode voltage swings.
• EMI Hardened Inputs: Features integrated electromagnetic interference (EMI) filtering to reduce sensitivity to external RF noise and high-frequency interference.

Common Applications

• Precision Current Sensing: Low-side and high-side shunt current measurement in battery management systems (BMS).
• Transducer & Sensor Conditioning: Amplifying thermocouple, RTD, strain gauge, and pressure bridge sensor signals.
• Portable Medical Instrumentation: Handheld blood glucose monitors, pulse oximeters, and patient health monitors.
• Battery-Powered Test Equipment: Precision multimeters, dataloggers, and remote environmental sensing nodes.

Usage Tips

• Power Supply Decoupling: Place a 0.1µF low-ESR ceramic bypass capacitor as close as possible between the V+ (Pin 8) and V- / GND (Pin 4) power pins to prevent high-frequency noise from affecting performance.
• PCB Layout for High Impedance: Because input bias currents are in the picoamp range, keep input traces short, clean, and isolated from high-speed digital lines; use a guard ring around input pins if operating in humid conditions.
• Capacitive Load Compensation: If driving heavy capacitive loads (greater than 100pF), use a small series isolation resistor (10Ω to 100Ω) at the output to maintain phase margin and avoid oscillation.
• Chopping Noise Filtering: The zero-drift architecture utilizes an internal chopping clock (~125kHz); add a simple low-pass RC filter at the output stage if your application is sensitive to high-frequency switching artifacts.

Datasheet