MC33978AES

Specialized Overview

The MC33978AES is a 22-channel multiple switch detection interface manufactured by NXP Semiconductors. It detects up to 22 switch contacts and transfers status via SPI. The device operates from 4.5 V to 36 V, with full parametric operation from 6.0 V to 28 V. It includes 14 Switch-to-Ground inputs and 8 Programmable Switch inputs. Features include a 24-to-1 analog multiplexer, active interrupt on state change, and selectable wetting currents of 2, 6, 8, 10, 12, 14, 16, or 20 mA. Low-power mode standby current is 30 μA for VBATP and 10 μA for VDDQ.

Specialized Feature Summary

• Supports Normal, Low-power, and Polling modes for optimized power consumption
• Integrates a 24-to-1 analog multiplexer with buffered AMUX output
• Includes integrated battery voltage sensing and die temperature monitoring
• Provides active interrupt signaling on switch state changes

Specialized Applications

• Automotive body control modules
• Industrial programmable logic controllers
• Process control systems
• Security and access panels

Specialized Procurement Notes

Verify the specific suffix AES corresponds to the QFN (WF-Type) 32-pin package when ordering. Confirm that the required operating temperature range aligns with the -40 °C to 125 °C specification. Ensure external reverse battery protection components are included in the design as the IC requires them for proper functionality.

Specialized Selection Notes

Select this variant if a compact QFN footprint is required instead of the SOICW or LQFP options. Consider the thermal resistance characteristics of the QFN package for heat dissipation requirements. Verify compatibility with the system's available PCB space and routing constraints associated with the 32-pin WF-Type package.

Specialized Part Context

This component belongs to the MC33978 family of switch detection interfaces. Other variants include the MC33978AAE in an LQFP-EP 48-pin package and the MC33978EK/AEK in an SOICW-EP 32-pin package. All variants share identical electrical specifications and functional capabilities, differing only in physical packaging.

Specialized Replacement Considerations

Direct replacements within the same family include MC33978AEK and MC33978EK. These parts offer identical functionality but utilize different packages. Ensure the replacement package fits the existing board layout or modify the design accordingly.