MAX17499/MAX17500 19-5485 Rev 1 7/11 Current-Mode PWM Controllers with Programmable Switching Frequency General Description Features The MAX17499/MAX17500 current-mode PWM con- Current-Mode Control trollers contain all the control circuitry required for the Programmable Switching Frequency Up to 625kHz design of wide-input-voltage isolated and nonisolated Accurate UVLO Threshold (1%) power supplies. The MAX17499 is well suited for low input voltage (9.5V DC to 24V DC) power supplies. The Open-Drain UVLO Flag Output with Internal Delay MAX17500 is well suited for universal input (rectified 36V to 72V Telecom Voltage Range 85V AC to 265V AC) or telecom (-36V DC to -72V DC) Universal Offline Input Voltage Range power supplies. Rectified 85V AC to 265V AC (MAX17500) The ICs contain an internal error amplifier that regulates 9.5V to 24V Input (MAX17499) the tertiary winding output voltage that is used in prima- ry-side-regulated isolated power supplies. Primary-side Digital Soft-Start regulation eliminates the need for an optocoupler. An Internal Bootstrap UVLO with Large Hysteresis input undervoltage lockout (UVLO) is provided for pro- (MAX17500) gramming the input-supply start voltage and to ensure Internal Error Amplifier with 1.5% Accurate proper operation during brownout conditions. An open- Reference drain UVLO flag output, with 210s internal delay, allows the sequencing of a secondary-side controller. 50A (typ) Startup Supply Current The input-supply start voltage is externally programma- 50% Maximum Duty-Cycle Limit ble with a voltage-divider. A UVLO/EN input is used to (MAX17499A/MAX17500A) shut down the devices. Internal digital soft-start elimi- 75% Maximum Duty-Cycle Limit nates output voltage overshoot. (MAX17499B/MAX17500B) The MAX17500 has an internal bootstrap UVLO with 60ns Cycle-by-Cycle Current-Limit Propagation large hysteresis that requires a minimum 23.6V for start- Delay up. The MAX17499 does not have the internal bootstrap UVLO and can be biased directly from a minimum volt- Available in Tiny 10-Pin MAX Packages age of 9.5V. Applications The switching frequency for the ICs is programmable 1/2, 1/4, and 1/8 Brick Power Modules with an external resistor. The MAX17499A/MAX17500A provide a 50% maximum duty-cycle limit, while the High-Efficiency, Isolated Telecom Power MAX17499B/MAX17500B provide a 75% maximum Supplies duty-cycle limit. These devices are available in 10-pin Networking/Servers MAX packages and are rated for operation over the -40C to +125C temperature range. Isolated Keep-Alive Power Supplies 12V Boost and SEPIC Regulators Isolated and Nonisolated High-Brightness LED Selector Guide appears at end of data sheet. Power Supplies MAX is a registered trademark of Maxim Integrated Products, Inc. Industrial Power Conversion Ordering Information PART D (%) STARTUP VOLTAGE (V) TEMP RANGE PIN-PACKAGE MAX MAX17499AAUB+ 50 9.5 -40C to +125C 10 MAX MAX17499BAUB+ 75 9.5 -40C to +125C 10 MAX MAX17500AAUB+ 50 22 -40C to +125C 10 MAX MAX17500BAUB+ 75 22 -40C to +125C 10 MAX Warning: The ICs are designed to work with high voltages. Exercise caution. +Denotes a lead(Pb)-free/RoHS-compliant package. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLECurrent-Mode PWM Controllers with Programmable Switching Frequency ABSOLUTE MAXIMUM RATINGS IN to GND...............................................................-0.3V to +30V Continuous Power Dissipation (T = +70C) A IN Clamp (internal shunt) Current.........................................5mA 10-Pin MAX (derate 5.6mW/C above +70C) ........444.4mW V to GND............................................................-0.3V to +13V Operating Temperature Range .........................-40C to +125C CC FB, COMP, UVLO/EN, RT, CS to GND.....................-0.3V to +6V Storage Temperature Range ............................-65C to +150C UFLG to GND .........................................................-0.3V to +30V Junction Temperature......................................................+150C NDRV to GND.............................................-0.3V to (V + 0.3V) CC Lead Temperature (soldering, 10s) .................................+300C Soldering Temperature (reflow) .......................................+260C 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 = +12V (for MAX17500, bring V up to 23.6V for startup), 10nF bypass capacitors at IN and V , R12 = 15k (MAX17499A/ IN IN CC MAX17500A), R12 = 7.5k (MAX17499B/MAX17500B), R15 = 1k, C6 = 100nF (see the Typical Application Circuit), NDRV = open, V = +1.4V, V = +1.0V, COMP = open, V = 0V, T = -40C to +125C, unless otherwise noted. Typical values are at T = UVLO/EN FB CS A A +25C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS UVLO/STARTUP Bootstrap UVLO Wake-Up Level V V rising (MAX17500 only) 19.68 21.6 23.60 V SUVR IN Bootstrap UVLO Shutdown Level V V falling (MAX17500 only) 9.05 9.74 10.43 V SUVF IN UVLO/EN Wake-Up Threshold V UVLO/EN rising 1.215 1.23 1.245 V ULR2 UVLO/EN Shutdown Threshold V UVLO/EN falling 1.14 1.17 1.20 V ULF2 UVLO/EN Input Current I V 2V -50 +50 nA UVLO UVLO/EN UVLO/EN Hysteresis 60 mV V = 19V, MAX17500 only when in IN IN Supply Current In UVLO I 50 90 A START bootstrap UVLO IN Input Voltage Range V MAX17499 only 9.5 24.0 V IN UVLO/EN steps up from 1V to 1.4V 3 UVLO/EN to UFLG Propagation s Delay (Figure 3) UVLO/EN steps down from 1.4V to 1V 0.6 t UVLO/EN steps up from 1V to 1.4V 3 10 ms EXTR UVLO/EN to NDRV Propagation Delay (Figure 3) t UVLO/EN steps down from 1.4V to 1V 150 210 300 s EXTF V steps up from 9V to 24V (MAX17500 IN t 5 BUVR only) Bootstrap UVLO Propagation s Delay V steps down from 24V to 9V IN t 1 BUVF (MAX17500 only) UFLG Low Output Voltage V I = 5mA sinking 1.5 V UFLG UFLG UFLG High Output Leakage V = 25V 0.1 1 A UFLG Current INTERNAL SUPPLY V = 10.8V to 24V, sinking 1A to 20mA IN V Regulator Set Point V 7.0 10.5 V CC CCSP from V CC IN Supply Current After Startup I V = 24V 2 4 mA IN IN Shutdown Supply Current UVLO/EN = low 50 90 A 2 MAX17499/MAX17500