MAX291EWE+T

Overview

The MAX291EWE+T is an 8th-order lowpass switched-capacitor filter in a 16-pin wide SO package. It provides a Butterworth response with a corner frequency range of 0.1Hz to 25kHz, controlled by a clock-to-corner-frequency ratio of 100:1. Operating on dual supplies from ±2.375V to ±5.5V or a single +4.75V to +11V supply, it draws 15mA typical current at ±5V. The device features an internal oscillator requiring only an external capacitor, an uncommitted op amp for auxiliary filtering, and operates within a -40°C to +85°C temperature range.

Feature Summary

• 8th-order lowpass switched-capacitor architecture providing maximally flat Butterworth passband response
• Clock-tunable corner frequency capability ranging from 0.1Hz to 25kHz via internal or external clock sources
• Integrated uncommitted operational amplifier suitable for post-filtering or anti-aliasing applications
• Single-supply or dual-supply operation eliminating the need for external resistors or capacitors

Applications

• ADC anti-aliasing filter
• DAC post-filtering
• Noise analysis
• 50Hz/60Hz line-noise filtering

Procurement Notes

Verify the specific suffix 'E' confirms the extended industrial temperature range of -40°C to +85°C. Confirm the 'WE' designation matches the required 16-pin wide SOIC physical footprint. Ensure the '+T' indicates tape-and-reel packaging if automated assembly is planned. Cross-reference the datasheet revision date against the manufacturing lot to ensure compliance with the latest electrical specifications.

Selection Notes

Select this component when a fixed 8th-order Butterworth response is required without external tuning components. The 100:1 clock-to-corner-frequency ratio allows precise control over the cutoff point. Consider the integrated op amp for additional signal conditioning. Verify that the available clock source can meet the minimum pulse width requirements for stable switching operation.

Part Context

This part belongs to the MAX291 series of easy-to-use switched-capacitor filters. It shares the same pinout and core architecture as the MAX292 (Bessel), MAX295, and MAX296 variants. The primary distinction lies in the frequency response characteristic; the MAX291 offers a maximally flat passband, whereas other family members provide different phase characteristics.

Replacement Considerations

MAX292EWE+T provides identical pinout and functionality but delivers a Bessel response instead of Butterworth.