Home Power management AC/DC & isolated DC/DC switching regulators PWM controllers

UC3876

LAST TIME BUY

Bipolar phase shifted full bridge controller with 15.25V/9.25V UVLO, 0°C to 70°C

UC3876 is in the process of being discontinued
Consider one of these alternates:
open-in-new Compare alternates
Similar functionality to the compared device
UCC28951 ACTIVE Green phase-shifted full-bridge controller with SR control for Wide input voltage Range Replacement

Product details

Topology Phase-shifted full bridge Control mode Current, Feedforward, Voltage Duty cycle (max) (%) 100 Switching frequency (max) (kHz) 1000 Features Error amplifier, Soft start, Soft switching, Synchronization pin UVLO thresholds on/off (V) 15.2/9.2 Operating temperature range (°C) 0 to 70 Rating Catalog Gate drive (typ) (A) 2 Vin (max) (V) 20
Topology Phase-shifted full bridge Control mode Current, Feedforward, Voltage Duty cycle (max) (%) 100 Switching frequency (max) (kHz) 1000 Features Error amplifier, Soft start, Soft switching, Synchronization pin UVLO thresholds on/off (V) 15.2/9.2 Operating temperature range (°C) 0 to 70 Rating Catalog Gate drive (typ) (A) 2 Vin (max) (V) 20
PDIP (N) 20 228.702 mm² 24.33 x 9.4
  • Zero to 100% Duty Cycle Control
  • Programmable Output Turn-On Delay
  • Compatible with Voltage or Current Mode Topologies
  • Practical Operation at Switching Frequencies to 1MHz
  • Four 2A Totem Pole Outputs
  • 10MHz Error Amplifier
  • Undervoltage Lockout
  • Low Startup Current—150µA
  • Outputs Active Low During UVLO
  • Soft-Start Control
  • Latched Over-Current Comparator With Full Cycle Restart
  • Trimmed Reference
  • Zero to 100% Duty Cycle Control
  • Programmable Output Turn-On Delay
  • Compatible with Voltage or Current Mode Topologies
  • Practical Operation at Switching Frequencies to 1MHz
  • Four 2A Totem Pole Outputs
  • 10MHz Error Amplifier
  • Undervoltage Lockout
  • Low Startup Current—150µA
  • Outputs Active Low During UVLO
  • Soft-Start Control
  • Latched Over-Current Comparator With Full Cycle Restart
  • Trimmed Reference

The UC1875 family of integrated circuits implements control of a bridge power stage by phase-shifting the switching of one half-bridge with respect to the other, allowing constant frequency pulse-width modulation in combination with resonant, zero-voltage switching for high efficiency performance at high frequencies. This family of circuits may be configured to provide control in either voltage or current mode operation, with a separate over-current shutdown for fast fault protection.

A programmable time delay is provided to insert a dead-time at the turn-on of each output stage. This delay, providing time to allow the resonant switching action, is independently controllable for each output pair (A-B, C-D).

With the oscillator capable of operation at frequencies in excess of 2MHz, overall switching frequencies to 1MHz are practical. In addition to the standard free running mode, with the CLOCKSYNC pin, the user may configure these devices to accept an external clock synchronization signal, or may lock together up to 5 units with the operational frequency determined by the fastest device.

Protective features include an undervoltage lockout which maintains all outputs in an active-low state until the supply reaches a 10.75V threshold. 1.5V hysteresis is built in for reliable, boot-strapped chip supply. Over-current protection is provided, and will latch the outputs in the OFF state within 70nsec of a fault. The current-fault circuitry implements full-cycle restart operation.

Additional features include an error amplifier with band-width in excess of 7MHz, a 5V reference, provisions for soft-starting, and flexible ramp generation and slope compensation circuitry.

These devices are available in 20-pin DIP, 28-pin "bat-wing" SOIC and 28 lead power PLCC plastic packages for operation over both 0°C to 70°C and –25°C to +85°C temperature ranges; and in hermetically sealed cerdip, and surface mount packages for –55°C to +125°C operation.

The UC1875 family of integrated circuits implements control of a bridge power stage by phase-shifting the switching of one half-bridge with respect to the other, allowing constant frequency pulse-width modulation in combination with resonant, zero-voltage switching for high efficiency performance at high frequencies. This family of circuits may be configured to provide control in either voltage or current mode operation, with a separate over-current shutdown for fast fault protection.

A programmable time delay is provided to insert a dead-time at the turn-on of each output stage. This delay, providing time to allow the resonant switching action, is independently controllable for each output pair (A-B, C-D).

With the oscillator capable of operation at frequencies in excess of 2MHz, overall switching frequencies to 1MHz are practical. In addition to the standard free running mode, with the CLOCKSYNC pin, the user may configure these devices to accept an external clock synchronization signal, or may lock together up to 5 units with the operational frequency determined by the fastest device.

Protective features include an undervoltage lockout which maintains all outputs in an active-low state until the supply reaches a 10.75V threshold. 1.5V hysteresis is built in for reliable, boot-strapped chip supply. Over-current protection is provided, and will latch the outputs in the OFF state within 70nsec of a fault. The current-fault circuitry implements full-cycle restart operation.

Additional features include an error amplifier with band-width in excess of 7MHz, a 5V reference, provisions for soft-starting, and flexible ramp generation and slope compensation circuitry.

These devices are available in 20-pin DIP, 28-pin "bat-wing" SOIC and 28 lead power PLCC plastic packages for operation over both 0°C to 70°C and –25°C to +85°C temperature ranges; and in hermetically sealed cerdip, and surface mount packages for –55°C to +125°C operation.

Download View video with transcript Video

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 4
Type Title Date
* Data sheet Phase Shift Resonant Controller datasheet (Rev. C) 24 May 2007
Selection guide Power Management Guide 2018 (Rev. R) 25 Jun 2018
Application note Phase Shifted Full Bridge, Zero Voltage Transition Design Considerations (Rev. A) 22 Jan 2011
Application note DN-63 The Current-Doubler Rectifier: An Alternative Rectification Technique 12 Jan 2001

Design & development

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

Package Pins Download
PDIP (N) 20 View options

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. ​​​​​​​​​​​​​​

Videos