The UAF42 is a universal active filter from Burr-Brown that can be configured for a wide range of low-pass, high-pass, and band-pass filters. It uses a classical state-variable analog architecture with an inverting amplifier and two integrators. The integrators include on-chip 1000pF capacitors trimmed to 0.5%. This solves one of the most difficult problems of active filter design—obtaining tight tolerance, low-loss capacitors. A DOS-compatible filter design program allows easy implementation of many filter types such as Butterworth, Bessel, and Chebyshev. A fourth, un-committed FET-input op amp (identical to the other three) can be used to form additional stages, or for special filters such as band-reject and Inverse Chebyshev. The classical topology of the UAF42 forms a time-continuous filter, free from the anomalies and switching noise associated with switched-capacitor filter types. The UAF42 is available in 14-pin plastic DIP and SOL-16 surface-mount packages, specified for the – 25°C to +85°C temperature range.
The UAF42 is a universal active filter that can be configured for low‑pass, high‑pass, band‑pass and band‑reject applications. It uses a state‑variable analog architecture with on‑chip 1000 pF capacitors trimmed to 0.5 % for tight tolerance.
The datasheet includes electrical specifications, pin configuration for DIP and SOIC packages, design‑program details, and recommended applications such as test equipment, communications, medical instrumentation and data‑acquisition systems.
| Frequency Range | 0 to 100 kHz |
|---|---|
| Maximum Q | 400 |
| Slew Rate | 10 V/µs |
| Gain‑Bandwidth Product | 4 MHz |
| Input Offset Voltage | +0.5 to +5 mV |
| Input Bias Current | 0 to 50 pA |
| Noise Density (10 Hz) | 25 nV/√Hz |
| Operating Temperature Range | -25 °C to +85 °C |
| Power Supply Voltage | +6 V to +18 V |
The UAF42 operates from 0 Hz up to 100 kHz.
The device has a slew rate of 10 V/µs.
The input offset voltage ranges from +0.5 mV to +5 mV.