UC2851

ACTIVE

32V, 1A , 0.5MHz off-line PWM controller , -40C to 85C

Product details

Vin (max) (V) 32 Operating temperature range (°C) -40 to 85 Control mode Current Topology Boost, Buck, Flyback, Forward Rating Catalog Features Error amplifier, Multi-topology, Soft start, Synchronization pin Duty cycle (max) (%) 50
Vin (max) (V) 32 Operating temperature range (°C) -40 to 85 Control mode Current Topology Boost, Buck, Flyback, Forward Rating Catalog Features Error amplifier, Multi-topology, Soft start, Synchronization pin Duty cycle (max) (%) 50
PDIP (N) 18 211.312 mm² 22.48 x 9.4 SOIC (DW) 18 118.965 mm² 11.55 x 10.3
  • All Control, Driving, Monitoring, and Protection Functions Included
  • Low-Current Off Line Start Circuit
  • Voltage Feed Forward or Current Mode Control
  • High Current Totem Pole Output
  • 50% Absolute Max Duty Cycle
  • PWM Latch for Single Pulse Per Period
  • Pulse-by-Pulse Current Limiting plus Shutdown for Over-Current Fault
  • No Start-Up or Shutdown Transients
  • Slow Turn-On Both Initially and After Fault Shutdown
  • Shutdown Upon Over or Under Voltage Sensing
  • Latch Off or Continuous Retry After Fault
  • 1% Reference Accuracy
  • 500kHz Operation
  • 18 Pin DIL or 20 Pin PLCC Package
  • All Control, Driving, Monitoring, and Protection Functions Included
  • Low-Current Off Line Start Circuit
  • Voltage Feed Forward or Current Mode Control
  • High Current Totem Pole Output
  • 50% Absolute Max Duty Cycle
  • PWM Latch for Single Pulse Per Period
  • Pulse-by-Pulse Current Limiting plus Shutdown for Over-Current Fault
  • No Start-Up or Shutdown Transients
  • Slow Turn-On Both Initially and After Fault Shutdown
  • Shutdown Upon Over or Under Voltage Sensing
  • Latch Off or Continuous Retry After Fault
  • 1% Reference Accuracy
  • 500kHz Operation
  • 18 Pin DIL or 20 Pin PLCC Package

The UC1851 family of PWM controllers are optimized for off-line primary side control. These devices include a high current totem pole output stage and a toggle flip-flop for absolute 50% duty cycle limiting. In all other respects this line of controllers is pin for pin compatible with the UC1841 series. Inclusion of all major housekeeping functions in these high performance controllers makes them ideal for use in cost sensitive applications.

Important features of these controllers include low current start-up, linear feed-forward for constant volt-second operation, and compatibility with both voltage or current mode control. In addition, these devices include a programmable start threshold, as well as programmable over-voltage, under-voltage, and over current fault thresholds. The fault latch on these devices can be configured for automatic restart, or latched off response to a fault.

These devices are packaged in 18-pin plastic or ceramic dual-in-line packages, or for surface mount applications, a 20 Pin PLCC. The UC1851 is characterized for -55°C to +125°C operation while the UC2851 and UC3851 are designed for -40°C to +85°C and 0°C to +70°C, respectively.

The UC1851 family of PWM controllers are optimized for off-line primary side control. These devices include a high current totem pole output stage and a toggle flip-flop for absolute 50% duty cycle limiting. In all other respects this line of controllers is pin for pin compatible with the UC1841 series. Inclusion of all major housekeeping functions in these high performance controllers makes them ideal for use in cost sensitive applications.

Important features of these controllers include low current start-up, linear feed-forward for constant volt-second operation, and compatibility with both voltage or current mode control. In addition, these devices include a programmable start threshold, as well as programmable over-voltage, under-voltage, and over current fault thresholds. The fault latch on these devices can be configured for automatic restart, or latched off response to a fault.

These devices are packaged in 18-pin plastic or ceramic dual-in-line packages, or for surface mount applications, a 20 Pin PLCC. The UC1851 is characterized for -55°C to +125°C operation while the UC2851 and UC3851 are designed for -40°C to +85°C and 0°C to +70°C, respectively.

Download

Similar products you might be interested in

open-in-new Compare alternates
Same functionality with different pin-out to the compared device
UCC28C53 ACTIVE Industrial, 30-V, low-power current-mode PWM controller, 8.4-V/7.6-V UVLO, 100% duty cycle Supports Buck, Boost, Flyback topologies

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 1
Type Title Date
* Data sheet Programmable, Off-Line, PWM Controller datasheet 05 Sep 1999

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

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. ​​​​​​​​​​​​​​