UC1825-SP

UC1825-SP www.ti.com SLUS870A – JANUARY 2009 – REVISED MARCH 2012 RAD-TOLERANT CLASS V, HIGH-SPEED PWM CONTROLLER Check for Samples: UC1825-SP FEATURES 1 QML-V Qualified, SMD 5962-87681 Rad-Tolerant: 30 kRad (Si) TID (1) Compatible With Voltage- or Current-Mode Topologies Practical Operation Switching Frequencies to 1 MHz 50-ns Propagation Delay-to-Output High-Current Dual Totem Pole Outputs (1.5 A Peak) Wide Bandwidth Error Amplifier Fully Latched Logic With Double-Pulse Suppression Pulse-by-Pulse Current Limiting Soft Start/Maximum Duty-Cycle Control Undervoltage Lockout With Hysteresis Low Start-Up Current (1.1 mA) (1) Radiation tolerance is a typical value based upon initial device qualification with dose rate = 10 mrad/sec. Radiation Lot Acceptance Testing is available - contact factory for details. DESCRIPTION The UC1825 PWM control device is optimized for high-frequency switched mode power supply applications. Particular care was given to minimizing propagation delays through the comparators and logic circuitry while maximizing bandwidth and slew rate of the error amplifier. This controller is designed for use in either current-mode or voltage mode systems with the capability for input voltage feedforward. Protection circuitry includes a current limit comparator with a 1-V threshold, a TTL compatible shutdown port, and a soft start pin which will double as a maximum duty-cycle clamp. The logic is fully latched to provide jitter-free operati...