L4979D-E

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Overview

The L4979D-E is an automotive-grade low dropout linear regulator manufactured by STMicroelectronics. It integrates microprocessor control functions, including a low voltage reset circuit and a watchdog timer. The device operates with an input voltage range of 5.6 V to 31 V and provides a fixed 5 V output. It features high precision output voltage accuracy of +/-2% over the full temperature range. The regulator includes thermal shutdown and short-circuit protection, ensuring reliable operation in demanding environments.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Feature Summary

• Integrates low voltage reset and programmable watchdog timer for microprocessor system supervision
• AEC-Q100 qualified for automotive reliability standards
• Features ultra-low quiescent current consumption when disabled
• Includes internal thermal shutdown and output short-circuit protection

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Applications

• Automotive electronic control units (ECUs)
• Microprocessor power supply systems
• Industrial control modules requiring reset supervision

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Procurement Notes

Verify the specific suffix 'E' against the official datasheet to confirm package type and tape/reel specifications. Ensure the application requires the fixed 5V output variant. Confirm AEC-Q100 qualification requirements are met for the target automotive environment. Check lead times as automotive components may have extended delivery periods.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Selection Notes

Select this component when a stable 5V rail is required alongside integrated system supervision. The L4979D-E is suitable for designs needing low standby current and robust fault protection. Compare dropout voltage characteristics against load requirements. Consider the 8-SOIC package constraints for PCB layout and thermal management.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Part Context

This part belongs to the L4979 series of low dropout regulators designed specifically for automotive applications. The series emphasizes integration of power regulation with essential monitoring functions. It serves as a dedicated power management solution for microcontrollers in vehicles. The family offers various output voltage options while maintaining consistent control features.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators FAQ

What is the typical quiescent current when the enable pin is low?

The typical quiescent current drops to 6 μA at 25 °C when the regulator is disabled.

How is the watchdog timer configured?

The watchdog timer is programmable using an external capacitor connected to the designated pin.