MC33997DW

Overview

The MC33997DW is a medium-power, multi-output power supply integrated circuit designed for automotive applications. It operates within an input voltage range of 6.0 V to 26.5 V, supporting 40 V transient conditions. The device integrates a sensorless current mode control step-down switching controller that regulates directly to a 5.0 V output (VDDH) capable of delivering up to 1400 mA total current. Additionally, it features a 3.3 V linear regulator (VDDL) utilizing an external pass transistor for 400 mA output, a low-power standby linear regulator (VKAM) providing 3.3 V at 10 mA, and two protected 5.0 V sensor supplies (VREF) each rated for 200 mA typical current.

Feature Summary

• Integrates a step-down switching controller with a dedicated 5.0 V high-current output and multiple linear regulators for diverse load requirements.
• Provides enhanced protection mechanisms including short-to-battery and short-to-ground protection with retry capability for sensor supplies.
• Supports advanced microprocessor architectures through built-in power sequencing, reset signals, and undervoltage shutdown with retry functionality.

Applications

• Automotive electronic control units requiring robust power management
• Microprocessor power supply systems with specific sequencing requirements
• Sensor interface circuits needing protected auxiliary power rails

Procurement Notes

Verify the manufacturer designation carefully, as Freescale Semiconductor has undergone corporate restructuring and is now part of NXP Semiconductors. Ensure the ordering suffix matches the required package variant and temperature grade. Confirm availability status through authorized distributors, as legacy automotive components may have limited stock or end-of-life implications. Cross-reference the datasheet revision to ensure compatibility with current design specifications.

Selection Notes

Select this component when a single IC solution is needed to manage multiple voltage rails in an automotive environment. The integration of both switching and linear regulation reduces bill of materials count. Consider the thermal performance implications of the external pass transistor for the 3.3 V rail. Ensure the input voltage profile aligns with the specified 6.0 V to 26.5 V operating range and transient withstand capability.

Part Context

The MC33997 belongs to a family of power system basis chips designed for automotive microprocessors. It consolidates power generation, sequencing, and protection functions typically distributed across multiple discrete components. This integration supports compact board designs and improves reliability by minimizing interconnect points in critical power delivery paths.

Replacement Considerations

Check for direct pin-compatible alternatives from NXP or other automotive PMIC manufacturers if this part is discontinued. Verify that any substitute maintains the same output voltage levels, current capabilities, and protection features. Ensure the replacement supports the required SPI or parallel interface for configuration if applicable.