The first zero-drift, zero-crossover operational amplifier

The OPA388 op amp maintains high precision across the entire input range for a variety of industrial applications, including test and measurement, medical and safety equipment, and high-resolution data-acquisition systems.

The architecture of the OPA388 produces a combination of high input linearity and precision. TI’s zero-drift technology eliminates temperature drift and flicker noise to attain the highest DC precision and dynamic error correction, while its zero-crossover topology eliminates offset errors caused by common-mode limitations to achieve linear output and true rail-to-rail input operation.

Key features and benefits of the OPA388 op amp

• Delivers true precision with high input linearity: The device’s zero-crossover topology eliminates the input offset transition region of traditional complementary metal-oxide semiconductor (CMOS) op amps, assuring maximum linearity and minimal distortion across the entire common-mode input range.
• Provides high DC precision: TI’s zero-drift technology delivers a low maximum offset voltage of 5µV, a typical offset voltage drift of 0.005μV/°C and a maximum input bias current of 700pA over the extended industrial temperature range of -40 to 125°C. This eliminates the need for costly overtemperature calibration and increases DC precision.
• Supports wide-bandwidth operation: With a 10MHz gain bandwidth product (GBW), the OPA388 enables high gain configurations and makes it possible to acquire a wide range of signal types and frequencies to support equipment from precision weigh scales to heart-rate monitors.
• Maintains low distortion for high performance: The ultra-low total harmonic distortion of -132dBc and voltage noise of 7nV/√Hz help produce a high-resolution signal chain for specialised applications such as programmable logic controllers, precision field transmitters and motion-control equipment.
• Reduces complexity and cost: Merging zero-drift and zero-crossover technology reduces signal-chain complexity and external component count, allowing designers to minimise board space and bill of materials (BOM) cost.

Tools and support to jump-start design
TI offers a range of support tools for designers using the OPA388, including a reference design that demonstrates how to use the precision op amp to eliminate crossover nonlinearity in digital-to-analogue converters. The reference design uses the DAC8830 precision data converter and REF5050 voltage reference, which combine to create an accurate DC calibration system for high-precision applications used in wireless infrastructure and test and measurement.

Package, availability and pricing
The OPA388 is available now through the TI store and authorised distributors. It is priced at $0.98 in 1,000-unit quantities and comes in a 4.9x3.9mm small-outline integrated circuit (SOIC) package.