UC3842J Texas Instruments Integrated Circuit (Ceramic Dual-In-Line Packages) In Stock
The Texas Instruments UC3842J is a current-mode PWM controller IC for DC-DC switching converters, operating from an 11.5 V to 28 V input in an 8-pin ceramic DIP package. It features an internal oscillator, error amplifier, and cycle-by-cycle current limiting for reliable flyback and forward converter designs. Available from $1.20 in stock with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Ceramic Dual-In-Line Packages
- Pin Count
- 8
- Lifecycle
- ACTIVE
- Datasheet
- UC3842J Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $7.6000(MOQ 25)
- 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 cycle-by-cycle current limiting for inherent short-circuit protection in switching power supplies
- Internal oscillator programmable up to 500 kHz allowing high-frequency compact power supply designs
- 8-pin ceramic DIP package offering excellent thermal stability for industrial and military-grade environments
Applications
The UC3842J is a classic PWM controller widely used in off-line flyback converters, forward converters, and DC-DC supplies in industrial power equipment and telecom power systems. Its current-mode control architecture simplifies compensation network design and provides fast response to load transients in battery chargers and switching regulators. It is also a popular choice for replacement and repair of legacy power supply designs due to its long production history and wide availability.
Specifications
| Pbfree Code | Yes |
| YTEOL | 15 |
| Analog IC - Other Type | SWITCHING CONTROLLER |
| Control Mode | CURRENT-MODE |
| Control Technique | PULSE WIDTH MODULATION |
| Input Voltage-Max | 28V |
| Input Voltage-Min | 11.5V |
| Input Voltage-Nom | 15V |
| JESD-30 Code | R-GDIP-T8 |
| JESD-609 Code | e0 |
| Number of Functions | 1 |
| Output Current-Max | 1A |
| Output Voltage-Max | 5.1V |
| Output Voltage-Min | 4.9V |
| Output Voltage-Nom | 5V |
| Package Body Material | CERAMIC, GLASS-SEALED |
| Package Equivalence Code | DIP8,.3 |
| Package Shape | RECTANGULAR |
| Package Style | IN-LINE |
| Qualification Status | Not Qualified |
| Supply Current-Max (Isup) | 25mA |
| Supply Voltage-Max (Vsup) | 28V |
| Supply Voltage-Min (Vsup) | 16V |
| Supply Voltage-Nom (Vsup) | 11V |
| Surface Mount | NO |
| Switcher Configuration | BUCK-BOOST |
| Switching Frequency-Max | 500kHz |
| Technology | BIPOLAR |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | Tin/Lead (Sn/Pb) |
| Terminal Form | THROUGH-HOLE |
| Terminal Pitch | 2.54mm |
| Terminal Position | DUAL |
| Package | Ceramic Dual-In-Line Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.90 |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for UC3842J:
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BICMOS, PDIP8
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BICMOS, CDIP8
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BIPolar, PDIP8
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BICMOS, PDIP8
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BICMOS, PDIP8
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BIPolar, PDIP8
Frequently Asked Questions
What control mode does the UC3842J use?
The UC3842J uses current-mode PWM control, which senses the switch current on a cycle-by-cycle basis to regulate the output. This approach provides inherent overcurrent protection and simplifies the feedback loop compensation compared to voltage-mode control.
What is the input voltage range for the UC3842J?
The UC3842J requires a startup voltage of at least 16 V and operates continuously down to 11.5 V, with a maximum input voltage of 28 V, making it suitable for typical AC-DC offline power supply auxiliary supplies and industrial DC bus applications.
What switching frequency can the UC3842J achieve?
The oscillator frequency of the UC3842J is set by an external RC network and can be programmed from a few kilohertz up to approximately 500 kHz, giving designers flexibility to optimize transformer size versus switching loss tradeoffs.
What package does the UC3842J use?
The UC3842J is housed in an 8-pin ceramic dual in-line package (CDIP), which provides superior thermal and mechanical reliability compared to plastic DIP versions, making it suitable for industrial, military, and high-reliability aerospace power supply applications.
What are common replacements or alternatives for the UC3842J?
Direct functional equivalents include the UC2842J (military temperature range), the UC3842AN in plastic DIP, and the NCP3842 from ON Semiconductor. All share the same pinout and core control architecture, allowing drop-in substitution in most designs.
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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.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 25+ | $11.8800 | $297.00 |
| 500+ | $8.5500 | $4275.00 |
| 1000+ | $8.0800 | $8080.00 |
| 10000+ | $7.6000 | $76000.00 |
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