MAX17499BAUB+

The MAX17499BAUB+ from Maxim Integrated Products is a current-mode PWM controller with programmable switching frequency in 10 pin µMAX package. The IC contains an internal error amplifier that regulates the tertiary winding output voltage that is used in primary side regulated isolated power supplies. Primary side regulation eliminates the need for an optocoupler. An input undervoltage lockout (UVLO) is provided for programming the input supply start voltage and to ensure proper operation during brownout conditions. An open-drain UVLO flag output with 210µs internal delay allows the sequencing of a secondary-side controller. The input supply start voltage is externally programmable with a voltage-divider. A UVLO/EN input is used to shut down the devices. Internal digital soft-start eliminates output voltage overshoot. The MAX17499 does not have the internal bootstrap UVLO and can be biased directly from a minimum voltage of 9.5V.

• Input voltage range from 9.5V to 24V
• Current mode control
• Programmable switching frequency up to 625KHz
• Internal error amplifier with 1.5% accurate reference
• 50µA (typ) start-up supply current
• 75% maximum duty-cycle limit
• 60ns cycle by cycle current-limit propagation delay
• Switching frequency for the IC is programmable with an external resistor
• Operating temperature range from -40°C to 125°C