UC3842BN STMicroelectronics Integrated Circuit (Dual-In-Line Packages) In Stock

STMicroelectronics UC3842BN is a current-mode PWM controller supporting boost and flyback topologies at up to 500 kHz switching frequency and 1 A gate drive. Input voltage range is 11.5 V to 30 V in an 8-pin PDIP package. Available from stock with worldwide shipping.

ACTIVEIntegrated CircuitVerified May 2026
Package / Visual Reference
UC3842BNDual-In-Line Packages
Quick Facts
Manufacturer
STMicroelectronics
Package
Dual-In-Line Packages
Pin Count
8
Lifecycle
ACTIVE
Category
Integrated Circuit
Price
From $0.2268(MOQ 1)
Temp Range
?°C to 70.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

What are the key features of UC3842BN?

  • Current-mode PWM control with cycle-by-cycle peak current limiting for inherent short-circuit protection in boost and flyback designs
  • 500 kHz maximum switching frequency enabling compact transformer and filter design in isolated and non-isolated SMPS
  • 1 A gate drive output with 11.5 V to 30 V input range, compatible with a wide range of power MOSFET gate capacitances

What is UC3842BN used for?

The UC3842BN is used in offline flyback power supplies and DC-DC boost converters for industrial, telecom, and consumer electronics applications requiring reliable current-mode control at switching frequencies up to 500 kHz. Its 1 A gate drive capability supports medium-power MOSFET switching stages in adapter, battery charger, and auxiliary power module designs operating from 11.5 V to 30 V input rails.

What are the specifications of UC3842BN?

Factory Lead Time14Weeks
YTEOL6
Analog IC - Other TypeSWITCHING CONTROLLER
Control ModeCURRENT-MODE
Control TechniquePULSE WIDTH MODULATION
Input Voltage-Max30V
Input Voltage-Min11.5V
Input Voltage-Nom15V
JESD-30 CodeR-PDIP-T8
JESD-609 Codee3
Number of Functions1
Output Current-Max1A
Package Body MaterialPLASTIC/EPOXY
Package Equivalence CodeDIP8,.3
Package ShapeRECTANGULAR
Package StyleIN-LINE
Peak Reflow Temperature (Cel)NOT SPECIFIED
Qualification StatusNot Qualified
Surface MountNO
Switcher ConfigurationSINGLE
Switching Frequency-Max500kHz
TechnologyBIPOLAR
Temperature GradeCOMMERCIAL
Terminal FinishMatte Tin (Sn) - annealed
Terminal FormTHROUGH-HOLE
Terminal Pitch2.54mm
Terminal PositionDUAL
Time@Peak Reflow Temperature-Max (s)NOT SPECIFIED
## UC3842BN Alternates Showing resultsImage
PackageDual-In-Line Packages

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
ECCNEAR99
HTS Code8542.39.00.60
Country of OriginMainland China

Where can I find the UC3842BN datasheet?

UC3842BN Datasheet Download

Official datasheet from STMicroelectronics

What are equivalent replacements for UC3842BN?

Compatible alternatives and drop-in replacements for UC3842BN:

UC3842BNGonsemi

Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BIPolar, PDIP8

View Part →
UC3842AN

Rochester Electronics LLC 1 A SWITCHING CONTROLLER, 500 kHz SWITCHING FREQ-MAX, PDIP8, GREEN, PLASTIC, DIP-8

View Part →

Frequently Asked Questions

What switching frequency range does UC3842BN support, and how does it affect transformer size in a flyback design?

The UC3842BN operates at switching frequencies up to 500 kHz, which allows the use of significantly smaller flyback transformers and output filter capacitors compared to lower-frequency controllers. At 100 kHz a transformer might be 10x larger than at 500 kHz, directly reducing power supply size and weight in space-constrained industrial adapters.

How does current-mode control in UC3842BN improve transient response compared to voltage-mode PWM controllers?

UC3842BN's current-mode control senses the inductor or switch current on a cycle-by-cycle basis, providing inherent feedforward response to input voltage changes. This reduces the output filter requirement and achieves faster load transient response — typically settling within a few microseconds — compared to voltage-mode designs that rely solely on output voltage feedback.

What input voltage range does UC3842BN require, and is it suitable for a 24 V industrial supply rail?

The UC3842BN operates from 11.5 V minimum to 30 V maximum supply input, with 15 V as the nominal design point. A standard 24 V industrial rail falls comfortably within this range, making UC3842BN a direct fit for industrial SMPS controllers, DIN-rail power supplies, and motor drive auxiliary power circuits.

What gate drive current does UC3842BN deliver, and what MOSFET gate charge can it handle?

The UC3842BN provides 1 A peak gate drive current, capable of driving MOSFETs with gate charge up to approximately 100 nC at 500 kHz switching, which covers a wide range of medium-power switching transistors. For larger MOSFETs with higher gate charge, an external gate driver stage between UC3842BN and the FET is recommended.

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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 $0.2268
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
1+$0.2335$0.23
10+$0.2285$2.29
25+$0.2269$5.67
27+$0.2268$6.12
pcs
Unit price: $0.2335 · Total: $0.23

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

FindMyChip sourced our entire STM32 BOM in 48 hours when our usual distributor had 16-week lead times.

TM
Thomas Mueller
Hardware Lead, SensorTech GmbH, Germany