The MAX5052/MAX5053 current-mode PWM controllers contain all the control circuitry required for the design of wide-input-voltage isolated and nonisolated power supplies. The MAX5052AEUA is well suited for universal input (rectified 85VAC to 265VAC) or telecom (-36VDC to -72VDC) power supplies. The MAX5053 is well suited for low-input-voltage (10.8VDC to 24VDC) power supplies. The MAX5052/MAX5053 contain an internal error amplifier that regulates the tertiary winding output voltage. This implements a primary-side regulated, isolated power supply, eliminating 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. The input-supply start voltage is externally programmable with a voltage-divider. To shutdown the device, the UVLO pin is pulled low. Internal digital soft-start reduces output voltage overshoot. The internal thermal shutdown circuit protects the device in the event the junction temperature exceeds +130°C. The MAX5052AEUA has an internal bootstrap UVLO with large hysteresis that requires a minimum voltage of 23.6V for startup. The MAX5053 does not have the internal bootstrap UVLO and can be biased directly from a minimum voltage of 10.8V. The 262kHz switching frequency is internally trimmed to ±12% accuracy; this allows the optimization of the magnetic and filter components resulting in compact, cost-effective power supplies. The MAX5052A/MAX5053A are offered with a 50% maximum duty-cycle limit. The MAX5052B/MAX5053B are offered with a 75% maximum duty-cycle limit. These devices are available in 8-pin μMAX packages and operate over the -40°C to +85°C temperature range. 
Feature
 
 
  
  -  Available in a Tiny 8-Pin μMAX Package 
 
  -  Current-Mode Control 
 
  -  50W Output Power 
 
  -  Universal Offline Input Voltage Range 
   
 
    -  Rectified 85VAC to 265VAC (MAX5052) 
 
   
  
  -  VIN Directly Driven from 10.8V to 24V Input (MAX5053) 
 
  -  Digital Soft-Start 
 
  -  Programmable Input Startup Voltage 
 
  -  Internal Bootstrap UVLO with Large Hysteresis (MAX5052) 
 
  -  Internal Error Amplifier with 1% Accurate Reference 
 
  -  Thermal Shutdown 
 
  -  45μA (typ) Startup Supply Current 
 
  -  1.4mA (typ) Operating Supply Current 
 
  -  Fixed Switching Frequency of 262kHz ±12% 
 
  -  50% Maximum Duty-Cycle Limit (MAX5052A/MAX5053A) 
 
  -  75% Maximum Duty-Cycle Limit (MAX5052B/MAX5053B) 
 
  -  60ns Cycle-by-Cycle Current-Limit Response Time 
 
 
 
  
Applications
 
 
 
  - 12V Boost Regulators
 
  - 12V SEPIC Regulators
 
  - Computer Systems/Servers
 
  - Industrial Power Conversion
 
  - Isolated Keep-Alive Circuits
 
  - Isolated Telecom Power Supplies
 
  - Networking Systems
 
  - Power Supplies
 
  - Universal Input AC