UC3842TN STMicroelectronics Integrated Circuit (Dual-In-Line Packages) In Stock
The UC3842TN is a current-mode PWM controller IC for flyback, forward, and boost switch-mode power supplies from STMicroelectronics. It operates from 12 V to 30 V supply, supports up to 500 kHz switching frequency, and delivers 1 A peak gate drive current. Packaged in an 8-pin PDIP for through-hole SMPS designs.
- Manufacturer
- STMicroelectronics
- Package
- Dual-In-Line Packages
- Pin Count
- 8
- Lifecycle
- OBSOLETE
- Datasheet
- UC3842TN Datasheet PDF
- Category
- Integrated Circuit
- Temp Range
- ?°C to 105.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of UC3842TN?
- Current-mode PWM control with cycle-by-cycle current limiting for fast overload and short-circuit protection
- 1 A peak gate-drive output for direct MOSFET switching without external buffer transistors
- Operating supply range 12 V to 30 V with undervoltage lockout for reliable startup in off-line supplies
- Switching frequency programmable up to 500 kHz via external RC network for compact transformer designs
- 8-pin PDIP package simplifying prototyping and repair of industrial and consumer power supplies
What is UC3842TN used for?
The UC3842TN is a foundational current-mode PWM controller for offline flyback power supplies in adapters, chargers, industrial equipment, and motor drives requiring regulated outputs from AC mains inputs. Its cycle-by-cycle current limiting and internally fixed oscillator make it straightforward to implement stable buck, boost, and flyback topologies with MOSFET switches up to 500 kHz. The device is also widely used in retrofit and repair applications because its 8-pin PDIP pinout is industry-standard and interchangeable with numerous second-source equivalents from multiple manufacturers.
What are the specifications of UC3842TN?
| YTEOL | 0 |
| Analog IC - Other Type | SWITCHING CONTROLLER |
| Control Mode | CURRENT-MODE |
| Control Technique | PULSE WIDTH MODULATION |
| Input Voltage-Max | 30V |
| Input Voltage-Min | 12V |
| Input Voltage-Nom | 15V |
| JESD-30 Code | R-PDIP-T8 |
| Number of Functions | 1 |
| Output Current-Max | 1A |
| Package Body Material | PLASTIC/EPOXY |
| Package Shape | RECTANGULAR |
| Package Style | IN-LINE |
| Qualification Status | Not Qualified |
| Surface Mount | NO |
| Switcher Configuration | SINGLE |
| Switching Frequency-Max | 500kHz |
| Terminal Form | THROUGH-HOLE |
| Terminal Pitch | 2.54mm |
| Terminal Position | DUAL |
| ## UC3842TN Alternates Showing results | Image |
| Package | Dual-In-Line Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.60 |
Where can I find the UC3842TN datasheet?
UC3842TN Datasheet DownloadOfficial datasheet from STMicroelectronics
What are equivalent replacements for UC3842TN?
Compatible alternatives and drop-in replacements for UC3842TN:
Rochester Electronics LLC 1A SWITCHING CONTROLLER, 500kHz SWITCHING FREQ-MAX, PDIP8, HALOGEN AND LEAD FREE, PLASTIC, DIP-8
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BIPolar, PDIP8
suggested
suggested
suggested
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Frequently Asked Questions
Which designs are a good fit for UC3842TN with 12 V to 30 V?
UC3842TN fits industrial, embedded, and repair-oriented electronic assemblies when the design needs 12 V to 30 V and 30 V. It is a practical choice when the BOM also matches the 8-pin PDIP footprint.
How should engineers check package compatibility for UC3842TN?
Compare the PCB land pattern, height allowance, and assembly process against the 8-pin PDIP style. The 8 pins detail is the first check before approving a replacement.
What matters when sourcing UC3842TN as a replacement?
Confirm the same 12 V to 30 V, 30 V, manufacturer traceability, and lifecycle status before substituting it. Buyers should also verify stock for the exact 8-pin PDIP configuration.
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Why Buy from FindMyChip
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.
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