L4949ED-E STMicroelectronics Integrated Circuit (Small Outline Packages) In Stock

The L4949ED-E is an automotive-grade multifunction very low dropout voltage regulator from STMicroelectronics, delivering a fixed 5V output at up to 100mA with only 0.3V typical dropout. Housed in SOIC-8 package with AEC-Q100 qualification, it supports input voltages from 6V to 28V and includes built-in watchdog, reset, and inhibit functions. Available from authorized distributors with worldwide shipping.

OBSOLETEIntegrated CircuitVerified Jun 2026
Package / Visual Reference
L4949ED-ESmall Outline Packages
Quick Facts
Manufacturer
STMicroelectronics
Package
Small Outline Packages
Pin Count
8
Lifecycle
OBSOLETE
Category
Integrated Circuit
Price
From $0.4019(MOQ 535)
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

What are the key features of L4949ED-E?

  • Fixed 5V output with ultra-low 0.3V typical dropout voltage for automotive supply rail efficiency
  • AEC-Q100 qualified for automotive reliability across -40°C to +125°C temperature range
  • Integrated watchdog timer and reset functions reduce external component count in automotive ECUs
  • Wide 6V to 28V input voltage range covers automotive battery and load-dump conditions
  • SOIC-8 package enables compact PCB layout in space-constrained automotive modules

What is L4949ED-E used for?

The L4949ED-E is ideal for automotive body electronics, dashboard controllers, and engine control units requiring a stable 5V rail from the vehicle battery. Its integrated watchdog and reset functions make it well suited for microcontroller supply circuits in airbag, ABS, and powertrain modules. The device also fits industrial applications where a robust, low-dropout 5V regulator with supervisory features is needed.

What are the specifications of L4949ED-E?

YTEOL0
AdjustabilityFIXED
Dropout Voltage1-Max0.5V
Dropout Voltage1-Nom0.3V
Input Voltage Absolute-Max28V
Input Voltage-Max28V
Input Voltage-Min6V
JESD-30 CodeR-PDSO-G8
JESD-609 Codee3
Line Regulation-Max0.02%
Load Regulation-Max0.03%
Number of Functions1
Number of Outputs1
Operating Temperature TJ-Max125°C
Operating Temperature TJ-Min-40 °C
Output Current1-Max0.1A
Output Voltage1-Max5.25V
Output Voltage1-Min4.75V
Output Voltage1-Nom5V
Package Body MaterialPLASTIC/EPOXY
Package Equivalence CodeSOP8,.25
Package ShapeRECTANGULAR
Package StyleSMALL OUTLINE
Packing MethodTUBE
Peak Reflow Temperature (Cel)260
Qualification StatusNot Qualified
Regulator TypeFIXED POSITIVE SINGLE OUTPUT LDO REGULATOR
Surface MountYES
TechnologyBIPOLAR
Terminal FinishMatte Tin (Sn) - annealed
Terminal FormGULL WING
Terminal Pitch1.27mm
Terminal PositionDUAL
Time@Peak Reflow Temperature-Max (s)30
Voltage Tolerance-Max2%
PackageSmall Outline Packages

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
Moisture Sensitivity LevelMSL 3
ECCNEAR99
HTS Code8542.39.00.60

Where can I find the L4949ED-E datasheet?

L4949ED-E Datasheet Download

Official datasheet from STMicroelectronics

What are equivalent replacements for L4949ED-E?

Compatible alternatives and drop-in replacements for L4949ED-E:

L4949EPTR-ESTMicroelectronics Fixed Positive LDO

Regulator, 5V, 0.5V Dropout, BIPolar, PDSO20

View Part →
L4949EDTR-ESTMicroelectronics Fixed Positive LDO

Regulator, 5V, 0.5V Dropout, BIPolar, PDSO8

View Part →

Frequently Asked Questions

What is the minimum input voltage the L4949ED-E can accept while maintaining its 5V regulated output?

The L4949ED-E requires a minimum input voltage of 6V to maintain regulation at its fixed 5V output. With a typical dropout voltage of only 0.3V, the device can regulate effectively even when the supply drops close to 6V, making it suitable for automotive systems where battery voltage may dip during cold-crank events.

How much output current can the L4949ED-E supply, and is it sufficient for microcontroller-based automotive ECUs?

The L4949ED-E provides up to 100mA of continuous output current at 5V. This is sufficient to power low-power 8-bit or 32-bit microcontrollers, logic peripherals, and sensor interfaces in automotive ECUs, especially when heavier loads such as actuator drivers are powered separately from the main battery rail.

Which automotive temperature grade does the L4949ED-E meet, and what junction temperature range is supported?

The L4949ED-E is AEC-Q100 qualified for automotive applications and operates over a junction temperature range of -40°C to +125°C. This makes it reliable across the full under-hood thermal environment encountered in engine management, transmission control, and body control module designs.

Does the L4949ED-E include a watchdog timer, and how does that benefit automotive system designers?

Yes, the L4949ED-E integrates a watchdog timer and a reset output function directly on-chip. This eliminates the need for a separate supervisory IC, saving at least 1 component position on the PCB and reducing BOM cost. The watchdog monitors the microcontroller and asserts a reset signal if the processor stalls, improving system fault tolerance in safety-relevant automotive applications.

Related Guides

Why Buy from FindMyChip

Authorized Source
Verified supply chain with full traceability & inspection
Competitive Pricing
Factory-direct from China distributors, low MOQ
Fast Shipping
DHL Express 3–5 days · FedEx/UPS 5–7 days worldwide
Quality Guaranteed
30-day replacement for defective parts, no questions asked

About STMicroelectronics

STMicroelectronics is a global semiconductor leader serving customers across the spectrum of electronics applications. ST's products are found in a wide range of applications including automotive, industrial, personal electronics, and communications.

AvailabilityIn Stock
Reference Price (USD)
From $0.4019
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
535+$0.4354$232.94
690+$0.4193$289.32
865+$0.4019$347.64
pcs
Unit price: $0.4354 · Total: $232.94

In Stock · 24h Response · Worldwide Shipping

Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

Response within 24 hours · Worldwide shipping

The anti-counterfeit verification gave us confidence we'd never had with other China suppliers.

RP
Rajesh Patel
Procurement Manager, VoltEdge Energy, India