Peak-Current-Mode Controllers for Flyback and Boost Regulators

Enable Compact, Cost-Effective, and Highly Flexible Isolated/Nonisolated Power Supplies


The MAX17595/MAX17596/MAX17597 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 converters and telecom DC-DC (36V to 72V input range) power supplies. 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.

The MAX17595/MAX17596/MAX17597 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/MAX17596/MAX17597 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 ensuree 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.

MAX17595, MAX17596, MAX17597: Block Diagram MAX17595, MAX17596, MAX17597: Block Diagram Enlarge+

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


  • Battery-Powered Applications
  • Industrial and Telecom Applications
  • Universal Input Offline AC-DC Power Supplies
  • Wide-Range DC-Input Flyback/Boost Battery Chargers
Part Number Application (VIN) VIN
Topology Feedback Freq.
Duty Cycle
Gate Drive Current
Oper. Temp.
Package/Pins Budgetary
min max max max max max See Notes
Networking (48V)
Power Over Ethernet (32-58V)
Telecom (36-72V)
Universal Off-line (90-240VAC)
8 1000 Flyback
1000 48 0.032 2 1.5 -40 to +125
$0.68 @1k
Base Station (24V)
Industrial (24V)
4.5 36
$0.88 @1k
See All Isolated Power Supplies (25)

Part Number VIN
Output Adjust. Method Switch Type Power Good Signal ICC
Shutdown Mode Supply Current
Shutdown Mode Supply Current
DC-DC Outputs Oper. Freq.
Package/Pins Budgetary
min max min max max typ typ max See Notes
MAX17597  4.5 36 5 250 2 Resistor External Yes 2 20 32 1 1000
$0.88 @1k
See All Step-Up Switching Regulators (94)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

MAX17595EVKIT: Evaluation Kit for the MAX17595
MAX17597EVKIT: Evaluation Kit for the MAX17597 Boost Configuration
MAX17597FBEVKIT: Evaluation Kit for the MAX17597 Flyback Configuration
MAX17596EVKIT: Evaluation Kit for the MAX17596

Technical Documents

User Guide 5861 EE-SIM Design and Simulation Environment User Guide
App Note 5504 Designing Flyback Converters Using Peak-Current-Mode Controllers

Quality and Environmental Data

Request Reliability Report for: MAX17596 
Lead-Free Package Tin (Sn) Whisker Reports

Additional Resources

Topmark Coding MAX17596
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

Quality Management System >
Environmental Management System >

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