MAXREFDES1251: Single-Output Flyback Converter Using the MAX17596

The MAX17596 is a peak-current-mode controller for designing the wide input-voltage flyback regulators. The device offers input thresholds suitable for low-voltage DC-DC applications (4.5V–36V) and contains a built-in gate driver for an external n-channel metal-oxide semiconductor field-effect transistor (MOSFET). The MAX17596 houses an internal error amplifier with 1% accurate reference, eliminating the need for an external reference. The switching frequency is programmable from 100kHz to 1MHz with an accuracy of 8%, allowing optimization of magnetic and filter components, resulting in compact and cost-effective power conversion. For electromagnetic interference (EMI)-sensitive applications, the MAX17596 incorporates a programmable frequency dithering scheme, enabling low-EMI spread-spectrum operation. Users can start the power supply precisely at the desired input voltage, implement input overvoltage protection, and program soft-start time. A programmable slope compensation scheme is provided to ensure stability of the peak current-mode control scheme. Hiccup-mode overcurrent protection and thermal shutdown are provided to minimize dissipation in overcurrent and overtemperature fault conditions.

特征

Programmable Switching Frequency Allows Optimization of the Magnetic and Filter Components, Resulting in Compact, Cost-Effective, Efficient Isolated/Nonisolated Power Supplies
100kHz to 1MHz Programmable Switching Frequency with Optional Synchronization
Peak Current Mode Control Provides Excellent Transient Response
Programmable Frequency Dithering Enables Low EMI Spread-Spectrum Operation
Integrated Protection Features Enhance System Reliability
Adjustable Current Limit with External Current-Sense Resistor
Fast Cycle-By-Cycle Peak Current Limiting Hiccup-Mode Short-Circuit Protection
Overtemperature Protection
Programmable Soft-Start and Slope Compensation
Input Overvoltage Protection