The UC3879 is a phase-shift resonant controller with programmable output turn-on delay that is compatible with voltage mode or current mode topologies and can operate at switching frequencies up to 300 kHz.
The document provides a complete description of Texas Instruments' UC1879, UC2879 and UC3879 phase‑shift resonant controllers. It includes features, pin functions, electrical and thermal characteristics, mechanical dimensions, and safety notices.
Key sections cover the controller's programmable output delay, undervoltage lockout, over‑current protection, reference voltage, and synchronization options. Pin‑out diagrams and mechanical drawings aid in board layout and packaging decisions.
| Supply voltage (VC, VIN) | 20 V |
|---|---|
| Output current (source or sink) | 20 A |
| Undervoltage lockout start threshold (typical) | 10.75 V |
| Reference voltage (VREF) | 5 V |
The controller can operate with a supply voltage (VC, VIN) up to 20 V.
The DELSETA‑B and DELSETC‑D pins are used for output delay control of the corresponding output pairs.
By connecting their CLKSYNC pins together; the devices will lock to the fastest oscillator or to an external clock if provided.
The VREF pin provides a 5 V precision reference.