UC3842D8G4 Texas Instruments Integrated Circuit (Small Outline Packages) In Stock

The UC3842D8G4 is a current-mode PWM DC-DC controller IC from Texas Instruments supporting Boost, Buck, Flyback, and Forward topologies. It operates from an 11.5 V to 25 V input range and is housed in an 8-pin SOIC package with RoHS-compliant e4 rating. It delivers single-function isolated or non-isolated regulation for industrial power supply designs.

OBSOLETEIntegrated CircuitVerified Jun 2026
Package / Visual Reference
UC3842D8G4Small Outline Packages
Quick Facts
Manufacturer
Texas Instruments
Package
Small Outline Packages
Pin Count
8
Lifecycle
OBSOLETE
Category
Integrated Circuit
Temp Range
?°C to 70.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

Key Features

  • Current-mode PWM control with pulse-width modulation technique enabling cycle-by-cycle current limiting across Boost, Buck, Flyback, and Forward topologies
  • Wide 11.5 V to 25 V input voltage range with 15 V nominal operation, suitable for 12 V and 24 V industrial rail power conversion
  • 8-pin SOIC package with JESD-609 e4 RoHS-compliant rating for compact, lead-free power supply PCB designs in industrial environments

Applications

The UC3842D8G4 is widely used in off-line and DC-DC switching power supplies for industrial automation, telecom equipment, and embedded system power rails where a compact 8-pin current-mode PWM controller is required. Its support for Flyback and Forward topologies makes it suitable for isolated power converters in the 11.5 V to 25 V input range, such as 24 V DIN rail power supplies and isolated gate driver bias supplies. The device is also employed in battery charger front-ends and motor drive auxiliary power supplies where cycle-by-cycle current limiting improves fault protection.

Specifications

YTEOL0
Analog IC - Other TypeSWITCHING CONTROLLER
Control ModeCURRENT-MODE
Control TechniquePULSE WIDTH MODULATION
Input Voltage-Max25V
Input Voltage-Min11.5V
Input Voltage-Nom15V
JESD-30 CodeR-PDSO-G8
JESD-609 Codee4
Number of Functions1
Output Current-Max1A
Output Voltage-Min17V
Output Voltage-Nom5V
Package Body MaterialPLASTIC/EPOXY
Package Equivalence CodeSOP8,.25
Package ShapeRECTANGULAR
Package StyleSMALL OUTLINE
Peak Reflow Temperature (Cel)260
Qualification StatusNot Qualified
Supply Current-Max (Isup)17mA
Surface MountYES
Switcher ConfigurationSINGLE
Switching Frequency-Max500kHz
TechnologyBICMOS
Temperature GradeCOMMERCIAL
Terminal FinishNICKEL PALLADIUM GOLD
Terminal FormGULL WING
Terminal Pitch1.27mm
Terminal PositionDUAL
Time@Peak Reflow Temperature-Max (s)30
PackageSmall Outline Packages

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
Moisture Sensitivity LevelMSL 1
ECCNEAR99
HTS Code8542.39.00.60

Datasheet

UC3842D8G4 Datasheet Download

Official datasheet from Texas Instruments

Alternate & Equivalent Parts

Compatible alternatives and drop-in replacements for UC3842D8G4:

UC2842D8TRTexas Instruments

Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BICMOS, PDSO8

View Part →
UC3842D8Texas Instruments

Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BICMOS, PDSO8

View Part →

Frequently Asked Questions

What input voltage range does the UC3842D8G4 support for DC-DC power supply designs?

The UC3842D8G4 operates from a minimum of 11.5 V to a maximum of 25 V input, with a nominal design point of 15 V. This range makes it directly suitable for 12 V and 24 V bus power conversion systems found in industrial control, telecom, and embedded computing applications without requiring an additional pre-regulator.

Which converter topologies can be implemented using the UC3842D8G4?

The UC3842D8G4 supports Boost, Buck, Buck-Boost, Flyback, and Forward regulator topologies from a single 8-pin controller. Its current-mode PWM architecture with pulse-width modulation control inherently provides cycle-by-cycle peak current limiting, making all five topologies stable under overload conditions without additional external protection circuits.

How does current-mode control in the UC3842D8G4 improve transient response compared to voltage-mode controllers?

Current-mode PWM control in the UC3842D8G4 directly regulates inductor peak current on each switching cycle, which simplifies the compensation loop to a single-pole response and provides inherently faster load-transient recovery than voltage-mode designs. This results in tighter output voltage regulation during step-load changes common in industrial and computing power supplies.

Is the UC3842D8G4 suitable for isolated power converter designs such as Flyback supplies?

Yes, the UC3842D8G4 is explicitly rated for isolation-capable topologies including Flyback and Forward converters, as indicated by its product classification. Its 8-pin SOIC package includes a dedicated COMP pin and current sense input, allowing straightforward implementation of isolated Flyback supplies with an output optocoupler feedback path for regulation across the isolation barrier.

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About Texas Instruments

Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.

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MOQFrom 1 piece
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OriginChina (Authorized)

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