UAF42AU

Overview

The UAF42AU is a universal active filter in the SOIC-16 package, specified for operation between -25°C and +85°C. It utilizes a state-variable architecture with an inverting amplifier and two integrators containing monolithic 1000pF capacitors trimmed to ±0.5%. The device supports low-pass, high-pass, band-pass, and band-reject configurations up to 100 kHz. Key electrical parameters include a frequency accuracy of 1% at 1kHz, a maximum Q of 400, and a (Q • Frequency) product of 500 kHz. Operating voltage ranges from ±6V to ±18V, with typical supply current of ±7mA.

Feature Summary

• Monolithic integration of precision 1000pF capacitors eliminates external tolerance requirements
• State-variable topology provides simultaneous low-pass, high-pass, and band-pass outputs
• Uncommitted FET-input operational amplifier available for additional stages or special filter types

Applications

• Test equipment signal conditioning
• Medical instrumentation filtering
• Data acquisition system anti-aliasing
• Communications equipment channel selection

Procurement Notes

Verify the specific ordering suffix against the latest Package Option Addendum to confirm lead finish and environmental classification. Ensure the design accommodates the SOIC-16 thermal resistance of 100 °C/W. Confirm that the application voltage remains within the ±6V to ±18V operating range to maintain specified performance characteristics.

Selection Notes

Select the UAF42AU when precise capacitor matching is required without external components. The device is suitable for applications needing multiple filter responses from a single IC. Consider the 100 kHz frequency limit and 500 kHz (Q • Frequency) product when designing higher-frequency circuits. Verify pin compatibility if replacing legacy UAF41 designs.

Part Context

The UAF42AU belongs to the UAF42 Universal Active Filter family manufactured by Texas Instruments. It serves as a direct monolithic replacement for the older UAF41 model, offering improved slew rate and extended frequency range. The AU suffix specifically denotes the surface-mount SOIC-16 package variant designed for automated assembly processes.

Replacement Considerations

The UAF42AP is the pin-compatible through-hole alternative. For legacy designs, the UAF41 is functionally similar but has lower slew rate and frequency limits. Verify pinout differences between DIP and SOIC packages during retrofitting.