MAX5019/MAX5020 19-2115 Rev 0 7/01 Current-Mode PWM Controllers with Integrated Startup Circuit General Description Features The MAX5019/MAX5020 integrate all the building Wide Input Range: (18V to 110V) or (13V to 36V) blocks necessary for implementing DC-DC fixed-fre- Isolated (without optocoupler) or Nonisolated quency power supplies. Either primary- or secondary- Power Supply side regulation may be used to implement isolated or nonisolated power supplies. These devices are current- Current-Mode Control mode controllers with an integrated high-voltage start- Leading-Edge Blanking up circuit suitable for telecom/industrial voltage range power supplies. Current-mode control with leading- Internally Trimmed 275kHz 10% Oscillator edge blanking simplifies control-loop design and inter- Low External Component Count nal ramp compensation circuitry stabilizes the current Soft-Start loop when operating at duty cycles above 50% (MAX5019). The MAX5019 allows 85% operating duty High-Voltage Startup Circuit cycle and can be used to implement flyback converters Pulse-by-Pulse Current Limiting whereas the MAX5020 limits the operating duty cycle to less than 50% and can be used in single-ended for- Thermal Shutdown ward converters. A high-voltage startup circuit allows SO-8 Package these devices to draw power directly from the 18V to 110V input supply during startup. The switching fre- quency is internally trimmed to 275kHz 10%, thus Ordering Information reducing magnetics and filter component costs. The MAX5019/MAX5020 are available in 8-pin SO PART TEMP. RANGE PIN-PACKAGE packages. MAX5019CSA* 0C to +70C8-SO Warning: The MAX5019/MAX5020 operate with high MAX5019ESA* -40C to +85C8-SO voltages. Exercise caution. MAX5020CSA* 0C to +70C8-SO Applications MAX5020ESA* -40C to +85C8-SO *See Selector Guide at end of data sheet. Telecom Power Supplies Industrial Power Supplies Networking Power Supplies Isolated Power Supplies Typical Operating Circuit Pin Configuration V V IN OUT V+ TOP VIEW V DD MAX5020 V+ 1 8 V NDRV CC V CC V 2 7 NDRV DD CS MAX5019/ MAX5020 FB 3 6 GND SS SHDN GND SS SHDN 4 5 CS FB 8-SO Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.Current-Mode PWM Controllers with Integrated Startup Circuit ABSOLUTE MAXIMUM RATINGS V+ to GND...-0.3V to +120V Continuous Power Dissipation (T = +70C) A V to GND...-0.3V to +40V 8-Pin SO (derate 5.88mW/C above +70C) .....471mW DD V to GND..-0.3V to +12.5V Operating Temperature Range.....-40C to +85C CC FB, NDRV, SS SHDN, CS to GND .-0.3V to V + 0.3V Storage Temperature Range...-65C to +150C CC V and V Current .....20mA Lead Temperature (soldering, 10s) +300C DD CC NDRV Current Continuous....25mA NDRV Current for Less than 1s....1A Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = 13V, a 10F capacitor connects V to GND, V = 0, V+ = 48V, 0.1F capacitor connected from SS SHDN to GND, NDRV DD CC CS = open circuit, V = 3V, T = -40C to +85C, unless otherwise noted. Typical values are at T = +25C.) FB A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS SUPPLY CURRENT I V = 0, V+ = 110V, driver not switching 0.8 1.6 V+(NS) DD V+ Supply Current mA V+ = 110V, V = 0, FB = GND, DD I 1.6 3.0 V+(S) driver switching V+ Supply Current After Startup V+ = 110V, V = 13V, FB = GND 14 A DD I V = 36V, driver not switching 0.9 1.6 VDD(NS) DD V S upp l y Cur r ent mA D D I V = 36V, driver switching, FB = GND 2.1 3.0 VDD(S) DD V+ Shutdown Current V = 0, V+ = 110V 180 290 A SS SHDN V Shutdown Current V = 0 4 20 A DD SS SHDN PREREGULATOR/STARTUP V+ Input Voltage 18 110 V V Supply Voltage 13 36 V DD INTERNAL REGULATORS (V ) CC Powered from V+, I = 7.5mA, V = 0 7.5 9.8 12.0 V CC DD V Output Voltage CC Powered from V , I = 7.5mA 9.0 10.0 11.0 V DD CC V Undervoltage Lockout V V falling 6.6 V CC CC UVLO CC OUTPUT DRIVER Peak Source Current V = 11V (externally forced) 570 mA CC Peak Sink Current V = 11V (externally forced) 1000 mA CC NRDV High-Side Driver V = 11V, externally forced, CC R 412 OH Resistance NDRV sourcing 50mA NDRV Low-Side Driver V = 11V, externally forced, CC R 1.6 4 OL Resistance NDRV sinking 50mA ERROR AMPLIFIER FB Input Resistance R 50 k IN FB Input Bias Current I V V 1 A FB FB = SS SHDN Error Amplifier Gain (Inverting) A -20 V/V VCL Closed-Loop 3dB Bandwidth 200 kHz FB Input Voltage Range 23V 2 MAX5019/MAX5020