MAX17498C

EVALUATION KIT AVAILABLE MAX17498A/MAX17498B/MAX17498C AC-DC and DC-DC Peak Current-Mode Converters for Flyback/Boost Applications General Description 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 lowvoltage 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...