MAX4821ETP

Overview

The MAX4821ETP+ is an octal MOSFET power driver designed for +3.3V and +5V systems. It features eight independent low-side outputs capable of sourcing up to 70mA each. The device supports both serial and parallel interfaces, enabling cascaded operation for expanded channel control. Operating voltage ranges from 2.3V to 5.5V, with a quiescent current of 70µA. Rise and fall times are specified at 2µs. It is housed in a 20-pin TQFN package (4x4mm) and operates within a temperature range of -40°C to +85°C.

Feature Summary

• Cascadable architecture allows multiple units to be linked for increased channel density
• Integrated kickback protection safeguards against inductive load transients
• Dual interface modes support flexible system integration via serial or parallel control

Applications

• Relay driver circuits requiring high channel count
• Industrial automation control panels
• Telecommunications switching equipment

Procurement Notes

Verify the suffix designation carefully; the '+' indicates RoHS compliance. Confirm whether the required variant includes tape-and-reel packaging ('T' suffix) or tube packaging. Ensure the specific pinout matches the TQFN-EP-20 footprint requirements for your PCB layout. Cross-reference the datasheet revision level to confirm interface compatibility with your microcontroller.

Selection Notes

Select this component when an octal low-side driver is needed for +3.3V or +5V logic levels. It is suitable for applications requiring cascadability to manage more than eight loads. Consider the 70mA output current limit per channel when sizing for relay coils. Verify that the thermal performance of the TQFN package meets the power dissipation requirements of the specific application environment.

Part Context

This part belongs to the MAX4820/MAX4821 family of octal relay drivers. The MAX4821 specifically adds cascadable functionality compared to non-cascadable variants. It serves as a bridge between low-voltage digital logic and higher-power inductive loads like relays. The series is widely used in embedded systems requiring reliable switching capabilities.

Replacement Considerations

The MAX4820ETP+ is a related non-cascadable variant within the same family. Direct substitution requires verifying if the cascading feature is necessary for the design. Interface timing characteristics should be compared to ensure compatibility with existing control signals.