Home Power management AC/DC switching regulators AC/DC controllers

UC3845A

ACTIVE

30V,1A, 500KHz current mode PWM controller with 8.4V/7.6V UVLO 50% duty cycle, 0°C to 70°C

Product details

Topology Boost, Buck, Buck boost, Flyback, Forward Control mode Peak current mode Features Adjustable switching frequency, Current limiting, Dead time control, Error amplifier, Fixed frequency, Multi-topology Duty cycle (max) (%) 50
Topology Boost, Buck, Buck boost, Flyback, Forward Control mode Peak current mode Features Adjustable switching frequency, Current limiting, Dead time control, Error amplifier, Fixed frequency, Multi-topology Duty cycle (max) (%) 50
PDIP (P) 8 92.5083 mm² 9.81 x 9.43 SOIC (D) 8 29.4 mm² 4.9 x 6 SOIC (D) 14 51.9 mm² 8.65 x 6
  • Optimized for Off-Line and DC-DC Converters
  • Low Start-Up Current (< 0.5mA)
  • Trimmed Oscillator Discharge Current
  • Automatic Feedforward Compensation
  • Pulse-by-Pulse Current Limiting
  • Enhanced Load Response Characteristics
  • Undervoltage Lockout With Hysteresis
  • Double Pulse Suppression
  • High-Current Totem Pole Output
  • Internally-Trimmed Bandgap Reference
  • Up to 500kHz Operation
  • Create a Custom Design Using the UCx84xA With the WEBENCH Power Designer
  • Optimized for Off-Line and DC-DC Converters
  • Low Start-Up Current (< 0.5mA)
  • Trimmed Oscillator Discharge Current
  • Automatic Feedforward Compensation
  • Pulse-by-Pulse Current Limiting
  • Enhanced Load Response Characteristics
  • Undervoltage Lockout With Hysteresis
  • Double Pulse Suppression
  • High-Current Totem Pole Output
  • Internally-Trimmed Bandgap Reference
  • Up to 500kHz Operation
  • Create a Custom Design Using the UCx84xA With the WEBENCH Power Designer

The UCx84xA family of control devices is a pin-for-pin compatible improved version of the UCx84x family. Providing the necessary features to control current-mode or switched-mode power supplies, this family of devices has many improved features: startup current is less than 0.5mA, oscillator discharge is trimmed to 8.3mA, and during UVLO, the output stage can sink at least 10mA at less than 1.2V for VCC over 5V.

The UCx84xA family of control devices is a pin-for-pin compatible improved version of the UCx84x family. Providing the necessary features to control current-mode or switched-mode power supplies, this family of devices has many improved features: startup current is less than 0.5mA, oscillator discharge is trimmed to 8.3mA, and during UVLO, the output stage can sink at least 10mA at less than 1.2V for VCC over 5V.

Download View video with transcript Video

Similar products you might be interested in

open-in-new Compare alternates
Pin-for-pin with same functionality to the compared device
UC2845AQ ACTIVE Automotive single ended 500KHz current mode PWM controller with 8.5V/7.9V UVLO 50% duty cycle Wider temperature range
UCC28C55 ACTIVE Industrial, 30-V, low-power current-mode PWM controller, 8.4-V/7.6-V UVLO, 50% duty cycle Lower startup and supply current, better reference voltage accuracy and faster overcurrent protection
UCC38C45 ACTIVE Commercial, 20-V, low-power current-mode PWM controller, 8.4-V/7.6-V UVLO, 50% duty cycle Pin-to-pin equivalent with BiCMOS low-power consumption

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 12
Top documentation Type Title Format options Date
* Data sheet UCx84xA Current-Mode PWM Controller datasheet (Rev. H) PDF | HTML 11 Oct 2024
Application note Conditioning a Switch-mode Power Supply Current Signal Using TI Op Amps (Rev. A) PDF | HTML 11 Jun 2021
Application note Understanding Inverting Buck-Boost Power Stages in Switch Mode Power Supplies (Rev. B) 12 Mar 2019
Selection guide Power Management Guide 2018 (Rev. R) 25 Jun 2018
Application note UCC38C42 Family of High-Speed BiCMOS Current-Mode PWM Controllers 07 Feb 2002
Application note DN-26 UC3842A Low-Cost Start-up and Fault Protection Circuit 05 Sep 1999
Application note DN-27 UC1842/UC1842A Family - Summary of Functional Differences 05 Sep 1999
Application note DN-29 UC3842A Family - Frequency Foldback Technique Provides Protection 05 Sep 1999
Application note DN-30 Programmable Electronic Circuit Breaker 05 Sep 1999
Application note DN-40 The Effects of Oscillator Discharge Current Variations on Maximum Duty 05 Sep 1999
Application note DN-42A Design Considerations for Transitioning from UC3842 to the New UCC3802 05 Sep 1999
Application note U-111, Practical Considerations in Current Mode Power Supplies 05 Sep 1999

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Simulation model

UCCx8C45 Unencrypted PSpice Transient Model

SLUM533.ZIP (5 KB) - PSpice Model
Package Pins CAD symbols, footprints & 3D models
PDIP (P) 8 Ultra Librarian
SOIC (D) 8 Ultra Librarian
SOIC (D) 14 Ultra Librarian

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

Recommended products may have parameters, evaluation modules or reference designs related to this TI product.

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos