Soft Sw PWM Cntrlr 4-OUT PWM Controller 12V 550KHz 14-Pin TSSOP Tube

The UCC28230, UCC28231 PWM bus controllers are optimized for use in high efficiency, high power density, unregulated intermediate bus converters. Topologies include push-pull, half-bridge and full-bridge. External drivers, such asthe UCC27200 120-V high-side/low-side drivers, can be used with this controller.Low cost, small size and highly efficient solutions are provided by innovations such as:Start-up frequency control circuit allowing small output inductor andthe ability tostart with large intermediate bus capacitor. Load depended off-time control set by user.Additional 1-D control outputs can be used for primary winding clamping in self-driven output synchronous rectifier applications or as drive signals for the control-driven synchronous rectifier.Cycle-by-cycle current limit prevents overstresses of converter. If the over current condition causes less than 80% duty cycle at the output, then after a programmed time the controller proceeds into periodical shutdown and restart hiccup mode.The UCC28230 provides 5 V, and the UCC28231 provides 3.3-V precision reference voltages with 1.5% overall accuracy and 10-mA output current. This reference voltage can be used to supply housekeeping circuit and/or microcontroller. The precision reference voltage can also be used for accurate setting of system parameters. Other features include under-voltage lockout, thermal shut down, programmable soft start, over-current hiccup mode and short circuit protection with internal restart by default that can be set into latch-off mode by an external resistor. 

Programmable, Load Depended Off Time Control

Frequency Controlled Start Up Allows Small Output Inductor, Low Ripple and Constant Current Start with Large Output Capacitor

Two 0.2-A Push-Pull Outputs Provide Matched Control Signals D to External Drivers

Two Additional 1- D Outputs for Optimal Use of Self-Driven or Control Driven Synchronous Rectifiers

Unregulated, Fixed Volt-Second or Fixed Frequency Modes set by User

Two, 1.5% Overall Accuracy Reference Voltage Options: 5-V for UCC28230 and 3.3-V for UCC28231

Resistor Programmable Switching Frequency up to 1 MHz

Cycle-by-Cycle Current Limit Allows Parallel Operation with Droop Based Current Sharing

Single External Capacitor sets Soft-Start and Over Current Hiccup Mode Parameters with Restart

Severe Short Circuit Hiccup with Restart or Latch Off Protection Option by External Resistor

Input Under Voltage Lock Out

Thermal Shutdown

Thermally Enhanced 3 mm × 2 mm SON-12 and TSSOP-14 Package Options

APPLICATIONS

• Intermediate Bus Isolated Converters
• DC-to-DC Transformers