MAX7418EUA+T

Overview

The MAX7418EUA+T is a fifth-order, low-pass switched-capacitor filter (SCF) from the Analog Devices/MAXIM MAX7418–MAX7425 series. It features an elliptic response with a transition ratio of 1.6 and delivers approximately 53dB of stopband rejection. The device operates on a single +5V supply, drawing 3mA in active mode and 0.2μA in shutdown mode. It supports corner frequencies ranging from 1Hz to 30kHz via a 100:1 clock-to-corner frequency ratio. The component is housed in an 8-pin μMAX package and functions within a temperature range of -40°C to +85°C.

Feature Summary

• Elliptic filter response providing sharp rolloff and high stopband rejection
• Clock-tunable corner frequency adjustable from 1Hz to 30kHz
• Low-power operation with dedicated shutdown mode for minimal current draw
• Integrated offset adjust pin for DC output level tuning

Applications

• ADC anti-aliasing
• DAC post-filtering
• CT2 base stations
• Speech processing

Procurement Notes

Verify the specific suffix 'EUA' confirms the extended industrial temperature range (-40°C to +85°C) and the '+T' indicates reel packaging. Confirm that the Elliptic response variant matches the system requirements, as other variants in the family offer Bessel or Butterworth characteristics. Ensure the external clock circuitry aligns with the required 100:1 division ratio for the target cutoff frequency.

Selection Notes

Select this part when a steep roll-off is necessary to suppress out-of-band signals effectively. The elliptic response offers superior stopband attenuation compared to Butterworth or Bessel alternatives but introduces passband ripple. Verify that the input signal amplitude remains within limits to maintain optimal Total Harmonic Distortion plus Noise (THD+N) performance. Consider the internal oscillator capacitance requirements if self-clocking is preferred over an external clock source.

Part Context

This component belongs to the MAX7418–MAX7425 family of fifth-order low-pass switched-capacitor filters. While the broader series includes Bessel and Butterworth variants, the MAX7418 specifically provides an elliptic response optimized for applications requiring maximum stopband rejection. It shares the same physical footprint and basic interface with its siblings, differing primarily in frequency response characteristics and operating voltage requirements.

Replacement Considerations

Direct functional replacements within the same package include the MAX7422EUA+T, which shares the elliptic response and 1.6 transition ratio but operates at +3V instead of +5V. Other family members like the MAX7419EUA+T (Bessel) or MAX7420EUA+T (Butterworth) provide different frequency responses and should only be considered if the specific elliptic rolloff is not strictly required.