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.
- Manufacturer
- Texas Instruments
- Package
- Small Outline Packages
- Pin Count
- 8
- Lifecycle
- OBSOLETE
- Datasheet
- UC3842D8G4 Datasheet PDF
- Category
- Integrated Circuit
- 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 UC3842D8G4?
- 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
What is UC3842D8G4 used for?
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.
What are the specifications of UC3842D8G4?
| YTEOL | 0 |
| Analog IC - Other Type | SWITCHING CONTROLLER |
| Control Mode | CURRENT-MODE |
| Control Technique | PULSE WIDTH MODULATION |
| Input Voltage-Max | 25V |
| Input Voltage-Min | 11.5V |
| Input Voltage-Nom | 15V |
| JESD-30 Code | R-PDSO-G8 |
| JESD-609 Code | e4 |
| Number of Functions | 1 |
| Output Current-Max | 1A |
| Output Voltage-Min | 17V |
| Output Voltage-Nom | 5V |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SOP8,.25 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE |
| Peak Reflow Temperature (Cel) | 260 |
| Qualification Status | Not Qualified |
| Supply Current-Max (Isup) | 17mA |
| Surface Mount | YES |
| Switcher Configuration | SINGLE |
| Switching Frequency-Max | 500kHz |
| Technology | BICMOS |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | NICKEL PALLADIUM GOLD |
| Terminal Form | GULL WING |
| Terminal Pitch | 1.27mm |
| Terminal Position | DUAL |
| Time@Peak Reflow Temperature-Max (s) | 30 |
| Package | Small Outline Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.60 |
Where can I find the UC3842D8G4 datasheet?
UC3842D8G4 Datasheet DownloadOfficial datasheet from Texas Instruments
What are equivalent replacements for UC3842D8G4?
Compatible alternatives and drop-in replacements for UC3842D8G4:
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BICMOS, PDSO8
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BICMOS, PDSO8
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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Why Buy from FindMyChip
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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