MC33975EKR2

Specialized Overview

The MC33975EKR2 is a multiple switch detection interface with suppressed wake-up and 32 mA wetting current. It detects up to 22 switch contacts via SPI, supporting 8 programmable inputs (switch-to-battery or ground) and 14 switch-to-ground inputs. Operating from 5.5 V to 28 V on VPWR, it features selectable wetting currents of 32 mA or 4.0 mA for switch-to-ground inputs. Sleep state supply current is 100 µA at VPWR and 20 µA at VDD. The device includes a 22-to-1 analog multiplexer, programmable interrupt timers, and operates within -40 °C to 125 °C in a 32-pin SOICW EP package.

Specialized Feature Summary

• Detects up to 22 switch contacts with status transferred via SPI
• Features selectable wetting currents of 32 mA or 4.0 mA for switch-to-ground inputs
• Includes a 22-to-1 analog multiplexer for reading inputs as analog signals
• Provides low quiescent sleep state current for automotive and industrial applications

Specialized Applications

• Automotive systems
• Industrial control systems
• Process control systems
• Security systems
• Systems requiring switch status verification for safety, operation, or process control purposes

Specialized Procurement Notes

Verify the specific ordering suffix EK/R2 corresponds to the 32-pin SOICW EP package and Pb-free construction. Confirm the temperature range matches the application requirements, as the datasheet specifies -40 °C to 125 °C for this variant. Ensure external reverse battery protection is included in the design, as the VPWR pin requires it.

Specialized Selection Notes

Select the MC33975EKR2 when designing systems requiring ultra-low sleep currents and robust switch interfacing. Consider the 32 mA wetting current capability for reliable contact closure detection. Verify that the 3.3 V or 5.0 V logic levels on VDD are compatible with the target microcontroller's SPI interface specifications.

Specialized Part Context

The MC33975 is part of NXP's Multiple Switch Detection Interface family, designed to replace discrete components in switch monitoring circuits. It integrates switch ground offset protection, contact wetting current, and system wake-up functionality. The device utilizes SMARTMOS technology and is primarily intended for automotive applications but is also suitable for computer, telecommunications, and industrial controls.

Specialized Replacement Considerations

The MC33975ATEK/R2 is a documented variation with an extended switch input voltage range of -14 V to 40 V compared to the standard -14 V to 38 V. Verify if the higher transient voltage tolerance is required for the specific application environment before substituting.