Descripción

The OPA189, OPA2189, and OPA4189 (OPAx189) high-precision operational amplifiers are ultra-low noise, fast-settling, zero-drift devices that provide rail-to-rail output operation and feature a unique MUX friendly architecture and controlled start-up system. These features and excellent ac performance, combined with only 0.4 µV of offset voltage and 0.005µV/°C of drift over temperature for the single channel version, make the OPAx189 a great choice for precision instrumentation, signal measurement, and active filtering applications. Moreover, the MUX friendly input architecture prevents inrush current when applying large input differential voltages, which improves settling performance in multichannel systems, all while providing robust ESD protection during shipment, handling, and assembly.
All versions are specified from –40°C to +125°C.

 

Características

• Ultra-high precision:
– Zero-drift: 0.005 μV/°C (OPA189)
– Ultra-low offset voltage: 3 μV maximum (OPA189)
• Excellent dc precision:
– CMRR: 168 dB
– Open-loop gain: 170 dB
• Low noise:
– en at 1 kHz
– 0.1-Hz to 10-Hz noise: 0.1 µVPP
• Excellent dynamic performance:
– Gain bandwidth: 14 MHz
– Slew rate: 20 V/µs
– Fast settling: 10-V step, 0.01% in 1.1 µs
• Robust design:
– MUX-friendly inputs
– RFI/EMI filtered inputs
• Wide supply range: 4.5 V to 36 V
• Quiescent current: 1.7 mA (maximum)
• Rail-to-rail output
• Input includes negative rail

 

Aplicaciones

• Battery test
• Analog input module
• Weigh scale
• DC power supply, ac source, electronic load
• Multifunction relay

 

Visión general

The OPAx189 operational amplifiers combine precision offset and drift with excellent overall performance, making these devices an excellent choice for many precision applications. The precision offset drift of only 0.005 µV/°C provides stability over the entire temperature range. In addition, these devices offer excellent linear performance with high CMRR, PSRR, and AOL. As with all amplifiers, applications with noisy or high-impedance power supplies require decoupling capacitors close to the device pins. In most cases, 0.1-µF capacitors are adequate. See the Layout Guidelines section for details and layout example.
The OPAx189 are part of a family of zero-drift, MUX-friendly, rail-to-rail output operational amplifiers. These devices operate from 4.5 V to 36 V, are unity-gain stable, and are designed for a wide range of general-purpose and precision applications. The zero-drift architecture provides ultra-low input offset voltage and near-zero input offset voltage drift over temperature and time. This choice of architecture also offers outstanding ac performance, such as ultra-low broadband noise, zero flicker noise, and outstanding distortion performance when operating below the chopper frequency.

 

Descripción

The OPAx189 series of op amps can be used with single or dual supplies from an operating range of VS = 4.5 V (±2.25 V) up to VS = 36 V (±18 V). These devices do not require symmetrical supplies; they only require a minimum supply voltage of 4.5 V (±2.25 V). For VS less than ±2.5 V, the common-mode input range does not include midsupply. Supply voltages higher than 40 V can permanently damage the device; see the Absolute Maximum Ratings table for details. Key parameters are given over the specified temperature range, TA = –40°C to +125°C, in the Electrical Characteristics table. Key parameters that vary over the supply voltage, temperature range, or frequency are shown in the Typical Characteristics section.
The OPAx189 is unity-gain stable and free from unexpected output phase reversal. This device uses a proprietary, periodic autocalibration technique to provide low input offset voltage and very low input offset voltage drift over time and temperature. For lowest offset voltage and precision performance, optimize circuit layout and mechanical conditions. Avoid temperature gradients that create thermoelectric (Seebeck) effects in the thermocouple junctions formed from connecting dissimilar conductors. Cancel these thermally-generated potentials by ensuring they are equal on both input pins. Other layout and design considerations include:
• Use low thermoelectric-coefficient conditions (avoid dissimilar metals).
• Thermally isolate components from power supplies or other heat sources.
• Shield operational amplifier and input circuitry from air currents, such as cooling fans.