Peak-Current-Mode Controllers for Flyback and Boost Regulators
The MAX17595/MAX17596/MAX17597 from Maxim Integrated Products is a family of peak-current-mode controllers for design of wide input-voltage flyback and boost regulators. The MAX17595 offers optimized input thresholds for universal input ac-dc power supplies and telecom dc-dc converters (36V to 72V input range). The MAX17596/MAX17597 offer input thresholds suitable for low-voltage dc-dc applications (4.5V to 36V). The MAX17597 implements a boost converter. All three controllers contain a built-in gate driver for external n-channel MOSFETs.
These peak-current-mode controllers are targeted for use in battery-powered applications, industrial and telecommunications power systems, universal-input offline ac-dc power supplies and wide-range dc-input flyback/boost battery chargers.
The MAX17595/96/97 house 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 EMI-sensitive applications, the MAX17595/96/97 family 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.
Key Features
- Programmable Switching Frequency Allows Optimization of the Magnetic and Filter Components, Resulting in Compact, Cost-Effective, Efficient Isolated/Non-Isolated Power Supplies
- 100kHz to 1MHz Programmable Switching Frequency with Optional Synchronization
- Peak Current Mode Control Provides Excellent Transient Response
- Offline (Universal Input AC) and Telecom (36V to 72V) Flyback Controller—MAX17595
- DC-DC (4.5V to 36V) Flyback Controller—MAX17596
- Nonsynchronous (4.5V to 36V) Boost PWM Controller—MAX17597
- 3mm x 3mm TQFN Package
- 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
