UC2879 Series

Enhanced bipolar phase shifted full bridge controller with selectable UVLO, -40°C to 85°C

Catalog

Enhanced bipolar phase shifted full bridge controller with selectable UVLO, -40°C to 85°C

Part	Duty Cycle	Package / Case	Package / Case	Package / Case	Frequency - Switching	Output Isolation	Operating Temperature [Max]	Operating Temperature [Min]	Mounting Type	Fault Protection	Supplier Device Package	Topology	Control Features	Package / Case [y]	Package / Case [y]
Texas Instruments UC2879NG4	50 %	20-DIP	7.62 mm	0.3 in	300 kHz	Non-Isolated	85 °C	-40 °C	Through Hole	Current Limiting	20-PDIP	Full-Bridge	Frequency Control Soft Start Sync
Texas Instruments UC2879N	50 %	20-DIP	7.62 mm	0.3 in	300 kHz	Non-Isolated	85 °C	-40 °C	Through Hole	Current Limiting	20-PDIP	Full-Bridge	Frequency Control Soft Start Sync
Texas Instruments UC2879DWTR	50 %	20-SOIC			300 kHz	Non-Isolated	85 °C	-40 °C	Surface Mount	Current Limiting	20-SOIC	Full-Bridge	Frequency Control Soft Start Sync	0.295 in	7.5 mm
Texas Instruments UC2879DW	50 %	20-SOIC			300 kHz	Non-Isolated	85 °C	-40 °C	Surface Mount	Current Limiting	20-SOIC	Full-Bridge	Frequency Control Soft Start Sync	0.295 in	7.5 mm
Texas Instruments UC2879DWG4	50 %	20-SOIC			300 kHz	Non-Isolated	85 °C	-40 °C	Surface Mount	Current Limiting	20-SOIC	Full-Bridge	Frequency Control Soft Start Sync	0.295 in	7.5 mm
Texas Instruments UC2879DWTRG4	50 %	20-SOIC			300 kHz	Non-Isolated	85 °C	-40 °C	Surface Mount	Current Limiting	20-SOIC	Full-Bridge	Frequency Control Soft Start Sync	0.295 in	7.5 mm

Catalog

Enhanced bipolar phase shifted full bridge controller with selectable UVLO, -40°C to 85°C

Key Features

• Programmable Output Turn On Delay; Zero Delay AvailableCompatible with Voltage Mode or Current Mode TopologiesPractical Operation at Switching Frequencies to 300 kHz10-MHz Error AmplifierPin Programmable Undervoltage LockoutLow Startup Current — 150 µASoft Start ControlOutputs Active Low During UVLOProgrammable Output Turn On Delay; Zero Delay AvailableCompatible with Voltage Mode or Current Mode TopologiesPractical Operation at Switching Frequencies to 300 kHz10-MHz Error AmplifierPin Programmable Undervoltage LockoutLow Startup Current — 150 µASoft Start ControlOutputs Active Low During UVLO

Description

The UC3879 controls a bridge power stage by phase shifting the switching of one half-bridge with respect to the other. This allows constant frequency pulse width modulation in combination with resonant, zero-voltage switching for high efficiency performance. The UC3879 can be configured to provide control in either voltage mode or current mode operation, with overcurrent shutdown for fast fault protection. Independently programmable time delays provide dead-time at the turn-on of each output stage, allowing time for each resonant switching interval. With the oscillator capable of operating in excess of 600 kHz, overall output switching frequencies to 300 kHz are practical. In addition to the standard free running mode, with the CLKSYNC pin, the user may configure the UC3879 to accept an external clock synchronization signal. Alternatively, up to three units can be locked together with the operational frequency determined by the fastest device. Protective features include an undervoltage lockout and overcurrent protection. Additional features include a 10-MHz error amplifier, a 5-V precision reference, and soft start. The UC3879 is available in 20 pin N, J, DW, and Q and 28 pin L packages. The UC3879 controls a bridge power stage by phase shifting the switching of one half-bridge with respect to the other. This allows constant frequency pulse width modulation in combination with resonant, zero-voltage switching for high efficiency performance. The UC3879 can be configured to provide control in either voltage mode or current mode operation, with overcurrent shutdown for fast fault protection. Independently programmable time delays provide dead-time at the turn-on of each output stage, allowing time for each resonant switching interval. With the oscillator capable of operating in excess of 600 kHz, overall output switching frequencies to 300 kHz are practical. In addition to the standard free running mode, with the CLKSYNC pin, the user may configure the UC3879 to accept an external clock synchronization signal. Alternatively, up to three units can be locked together with the operational frequency determined by the fastest device. Protective features include an undervoltage lockout and overcurrent protection. Additional features include a 10-MHz error amplifier, a 5-V precision reference, and soft start. The UC3879 is available in 20 pin N, J, DW, and Q and 28 pin L packages.