UC3845AJ Texas Instruments Integrated Circuit (Ceramic Dual-In-Line Packages) In Stock
UC3845AJ is a current-mode PWM controller IC with 200 mA output drive, up to 500 kHz switching frequency, and 8.2 V to 28 V input voltage range in an 8-pin CDIP ceramic package. Provides precise pulse-width modulation for flyback, forward, and boost converter topologies. Designed for high-reliability power supply and industrial switching regulator applications.
- Manufacturer
- Texas Instruments
- Package
- Ceramic Dual-In-Line Packages
- Pin Count
- 8
- Lifecycle
- ACTIVE
- Datasheet
- UC3845AJ Datasheet PDF
- 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 cycle-by-cycle current limiting
- Switching frequency up to 500 kHz for compact magnetics design
- 200 mA totem-pole gate drive output
- Input voltage range 8.2 V to 28 V
- 8-pin ceramic DIP (CDIP) package for high-reliability environments
- Internal 5 V reference with 1% accuracy
- Soft-start and undervoltage lockout (UVLO) protection
Applications
UC3845AJ is used in isolated and non-isolated DC-DC converters, including flyback, forward, and boost topologies commonly found in industrial power supplies, telecom equipment, and motor drive gate drivers. Its current-mode control simplifies loop compensation and provides inherent overcurrent protection, making it a reliable choice for designs requiring stable regulation under varying load conditions. The ceramic DIP package suits high-temperature or high-reliability environments such as military, avionics, and industrial control panels.
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 | 8.2V |
| Input Voltage-Nom | 15V |
| JESD-30 Code | R-GDIP-T8 |
| JESD-609 Code | e0 |
| Number of Functions | 1 |
| Output Current-Max | 1A |
| 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) | 8.4V |
| Surface Mount | NO |
| Switcher Configuration | BUCK-BOOST |
| Switching Frequency-Max | 500kHz |
| Technology | BICMOS |
| 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 UC3845AJ:
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
Switching Controller, Current-mode, 1A, 500kHz Switching Freq-Max, BIPolar, PDIP8
Frequently Asked Questions
What output drive current and maximum switching frequency can UC3845AJ deliver for a flyback converter design?
UC3845AJ provides a 200 mA peak totem-pole gate drive output and supports switching frequencies up to 500 kHz, enabling compact transformer and filter designs while maintaining reliable MOSFET gate control in flyback or forward converter topologies.
What input voltage range must the bias supply meet to properly power UC3845AJ?
UC3845AJ requires a bias input voltage between 8.2 V and 28 V, with a nominal design point of 15 V. The built-in undervoltage lockout (UVLO) keeps the controller off until the supply reaches its startup threshold, preventing improper operation during power-up.
Why is the ceramic DIP package important for industrial or high-reliability power supply procurement?
The 8-pin CDIP ceramic package offers superior moisture resistance and wider operating temperature tolerance compared to plastic DIP variants, making UC3845AJ suitable for high-reliability procurement categories such as mil-spec, avionics, and industrial control where JESD-30 R-GDIP-T8 ceramic packaging is specified.
How does current-mode control in UC3845AJ simplify feedback loop compensation versus voltage-mode PWM?
Current-mode control uses the inductor current as an inner feedback signal, which reduces the converter transfer function to a single-pole response. This makes the outer voltage-feedback loop easier to compensate, typically requiring only a simple Type-II network, lowering component count and design time.
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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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