AC-DC and DC-DC Peak-Current-Mode Converters for Flyback/Boost Applications

Peak-Current-Mode Converters Enable Compact, Cost-Effective, and Highly Flexible Isolated/Nonisolated Power Supplies

Please check latest availability status for a specific part variant.


The MAX17498A/MAX17498B/MAX17498C devices are current-mode fixed-frequency flyback/boost converters with a minimum number of external components. They contain all the control circuitry required to design wide input voltage isolated and nonisolated power supplies. The MAX17498A has its rising/falling undervoltage lockout (UVLO) thresholds optimized for universal offline (85V AC to 265V AC) applications, while the MAX17498B/MAX17498C support UVLO thresholds suitable to low-voltage DC-DC applications.

The switching frequency of the MAX17498A/MAX17498C is 250kHz, while that of the MAX17498B is 500kHz. These frequencies allow the use of tiny magnetic and filter components, resulting in compact, cost-effective power supplies. An EN/UVLO input allows the user to start the power supply precisely at the desired input voltage, while also functioning as an on/off pin. The OVI pin enables implementation of an input overvoltage-protection scheme that ensures that the converter shuts down when the DC input voltage exceeds the desired maximum value.

The devices incorporate a flexible error amplifier and an accurate reference voltage (REF) to enable the end user to regulate both positive and negative outputs. Programmable current limit allows proper sizing and protection of the primary switching FET. The devices support a maximum duty cycle greater than 92% and provide programmable slope compensation to allow optimization of control loop performance. The devices provide an open-drain PGOOD pin that serves as a power-good indicator and enters the high-impedance state to indicate that the flyback/boost converter is in regulation. An SS pin allows programmable soft-start time for the flyback/boost converter. Hiccup-mode overcurrent protection and thermal shutdown are provided to minimize dissipation under overcurrent and overtemperature fault conditions. The devices are available in a space-saving, 16-pin (3mm x 3mm) TQFN package with 0.5mm lead spacing.

MAX17498A/MAX17498B/MAX17498C: Boost Power Supply MAX17498A/MAX17498B/MAX17498C: Boost Power Supply Enlarge+

Key Features

  • Peak Current-Mode Converter
  • Current-Mode Control Provides Excellent Transient Response
  • Fixed Switching Frequency
    • 250kHz: MAX17498A/MAX17498C
    • 500kHz: MAX17498B
  • Flexible Error Amplifier to Regulate Both Positive and Negative Outputs
  • Programmable Soft-Start to Reduce Input Inrush Current
  • Programmable Voltage or Current Soft-Start
  • Power-Good Signal (PGOOD)
  • Reduced Power Dissipation Under Fault
    • Overcurrent Protection
    • Thermal Shutdown with Hysteresis
  • Robust Protection Features
    • Programmable Current Limit
    • Input Overvoltage Protection
  • Optimized Loop Performance
    • Programmable Slope Compensation
  • High Efficiency
    • Low RDSON, 175mΩ, 65V Rated Internal n-Channel MOSFET
    • No Current-Sense Resistor
  • Optional Spread Spectrum
  • Space-Saving, 16-Pin (3mm x 3mm) TQFN Package


  • Front-End AC/DC Power Supplies for Industrial Applications (Isolated and Nonisolated)
  • Telecom Power Supplies
  • Wide Input Range DC Input Flyback/Boost Industrial Power Supplies

See parametric specs for Isolated Power Supplies (25)

Part NumberVIN
TopologySwitch TypeFeedbackFrequency
Duty Cycle
Oper. Temp.
minmaxmaxmaxmaxSee Notes
MAX17498A 4.51000Flyback-
250490.0363-40 to +125
$1.10 @1k
MAX17498B 36Internal50092-
$1.26 @1k
MAX17498C 36Internal250493
$1.37 @1k

See parametric specs for Step-Up Switching Regulators (101)

Part NumberVOUT1
Oper. Freq.
MAX17498B 1.25652500
See Data Sheet
MAX17498C 250
See Data Sheet

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.

MAX17498BEVKIT: Evaluation Kit for the MAX17498B
MAX17498BBEVKIT: Evaluation Kit for the MAX17498B

Tools & Models

  • MAX17498B Flyback
  • Product Reliability Reports: MAX17498B.pdf 
    Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C   Material Composition  

    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 >


    Related Resources