Current Mode PWM Controller 1A 10-Pin uMAX

The MAX15000/MAX15001 current-mode PWM controllers contain all the control circuitry required for the design of wide-input-voltage isolated and nonisolated power supplies. The MAX15000 is well suited for universal input (rectified 85VAC to 265VAC) or telecom (-36VDC to -72VDC) power supplies. The MAX15001 is well suited for low input voltage (9.5VDC to 24VDC) power supplies. The MAX15000/MAX15001 contain an internal error amplifier that regulates the tertiary winding output voltage which 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 shutdown the MAX15000/MAX15001. Internal digital soft-start eliminates output voltage overshoot. The MAX15000 has an internal bootstrap UVLO with large hysteresis that requires a minimum 23.6V for startup. The MAX15001 does not have the internal bootstrap UVLO and can be biased directly from a minimum voltage of 9.5V. The switching frequency for the MAX15000/MAX15001 is programmable with an external resistor. The MAX15000A/MAX15001A provide a 50% maximum duty-cycle limit, while the MAX15000B/MAX15001B provide a 75% maximum duty-cycle limit. These devices are available in 10-pin µMAX packages and are rated for operation over the -40°C to +85°C temperature range.

• Current-Mode Control
• Programmable Switching Frequency Up to 625kHz
• Accurate UVLO Threshold (1%)
• Open-Drain UVLO Flag Output with Internal Delay
• 36V to 72V Telecom Voltage Range
• Universal Offline Input Voltage Range
  • Rectified 85VAC to 265VAC (MAX15000)
• 9.5V to 24V Input (MAX15001)
• Digital Soft-Start
• Internal Bootstrap UVLO With Large Hysteresis(MAX15000)
• Internal Error Amplifier with 1.5% AccurateReference
• 50µA (typ) Startup Supply Current
• 50% Maximum Duty-Cycle Limit(MAX15000A/MAX15001A)
• 75% Maximum Duty-Cycle Limit(MAX15000B/MAX15001B)
• 60ns Cycle-by-Cycle Current-Limit PropagationDelay
• Available in Tiny 10-Pin µMAX Packages