FEATURES
DESCRIPTION
The UC184xA family of control ICs provides all the necessary features to implement off-line fixed-frequency, current-mode switching power supplies with a minimum of external components. The current mode architecture demonstrates improved load regulation, pulse-by-pulse current limiting and inherent protection of the power supply output switch. The IC includes: A bandgap reference trimmed to ±1% accuracy, an error amplifier, a current sense comparator with internal clamp to 1V, a high current totem pole output stage for fast switching of power MOSFET's, and an externally programmable oscillator to set frequency and maximum duty cycle. The undervoltage lock-out is designed to operate with 250µA typ. start-up current, allowing an efficient bootstrap supply voltage design.
KEY FEATURES
■ LOW START-UP CURRENT. (0.5mA max.)
■ TRIMMED OSCILLATOR DISCHARGE CURRENT. (See Product Highlight)
■ OPTIMIZED FOR OFF-LINE AND DC-TO-DC CONVERTERS.
■ AUTOMATIC FEED FORWARD COMPENSATION.
■ PULSE-BY-PULSE CURRENT LIMITING.
■ ENHANCED LOAD RESPONSE CHARACTERISTICS.
■ UNDER-VOLTAGE LOCKOUT WITH HYSTERESIS.
■ DOUBLE PULSE SUPPRESSION.
■ HIGH-CURRENT TOTEM POLE OUTPUT.
■ INTERNALLY TRIMMED BANDGAP REFERENCE.
■ 500KHz OPERATION.
■ LOW RO ERROR AMPLIFIER.
APPLICATIONS
■ ECONOMICAL OFF-LINE FLYBACK OR FORWARD CONVERTERS.
■ DC-DC BUCK OR BOOST CONVERTERS.
■ LOW COST DC MOTOR CONTROL.
Microchip Technology Inc. is a leading provider of microcontroller and analog semiconductors, providing low-risk product development, lower total system cost and faster time to market for thousands of diverse customer applications worldwide. Headquartered in Chandler, Arizona, Microchip offers outstanding technical support along with dependable delivery and quality.