MAX7423EUA+

Overview

The MAX7423EUA+ is a fifth-order, low-pass switched-capacitor filter (SCF) featuring a Bessel response. It operates from a single +3V supply and draws 3mA in normal mode, reducing to 0.2μA in shutdown. The corner frequency ranges from 1Hz to 45kHz with a 100:1 clock-to-corner ratio. Key parameters include ±4mV typical output offset voltage, 70dB power-supply rejection ratio, and 8-pin μMAX packaging. Operating temperature range is -40°C to +85°C.

Feature Summary

• Bessel filter response for low overshoot and fast settling
• Clock-tunable corner frequency from 1Hz to 45kHz
• Low-power operation with dedicated shutdown mode
• Single-supply compatibility with offset adjustment capability

Applications

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

Procurement Notes

Verify the component matches the exact part number MAX7423EUA+. Confirm the suffix 'E' indicates the extended industrial temperature range of -40°C to +85°C. Ensure the package type is 8-pin μMAX. Check RoHS compliance status as indicated by the '+' suffix. Validate supplier authenticity through authorized channels.

Selection Notes

Select this component when a Bessel response is required for minimal phase distortion. Use the internal oscillator or external clock to set the desired cutoff frequency within the 1Hz to 45kHz range. Ensure the system operates on a single +3V supply. Consider the shutdown pin for power management if low standby current is necessary.

Part Context

This device belongs to the MAX7418–MAX7425 family of fifth-order low-pass switched-capacitor filters. The MAX7423 variant specifically provides a Bessel response, distinguishing it from elliptic and Butterworth options in the series. All variants share similar pinouts and operational principles but differ in filter characteristics and supply voltage requirements.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.

FAQ

How is the corner frequency determined?

The corner frequency is determined by the clock frequency divided by 100. It can be set using an external clock or an internal oscillator controlled by an external capacitor.

What is the purpose of the OS pin?

The OS (Offset Adjust) pin allows for adjustment of the DC output level. It can be connected to COM if no offset adjustment is needed.

How does the shutdown mode work?

Driving the SHDN pin low activates shutdown mode, reducing supply current to 0.2μA and placing the output in a high-impedance state.