MAX8515A/MAX8515 2 . 0 0 7 m C m S 19-2528 Rev 1 2/03 Wide-Input 0.6V Shunt Regulators for Isolated DC-to-DC Converters General Description Features The MAX8515A/MAX8515 shunt regulators simplify the MAX8515A design of voltage regulation and overvoltage protection 0.6V 0.5% Initial Accuracy at +25C (OVP) functions in high-accuracy isolated DC-to-DC con- 0.6V 1% Accuracy from -40C to +85C verters with output voltages as low as 0.6V. The devices MAX8515 have supply voltage and feedback inputs separated from 0.6V 1% Initial Accuracy at +25C the output shunt stage, and can operate directly from the 0.6V 1.8% Accuracy from -40C to +85C DC-to-DC converter output stage when the output voltage is 1.8V to 18V. Alternately, the MAX8515A/MAX8515 input Sinks 20mA at 0.2V to 18V stage can be biased from an unregulated 1.7V to 28V Input Voltage Range from 1.7V to 28V supply, independent of DC-to-DC converter output volt- Directly Drives Optocouplers age. The MAX8515A/MAX8515 shunts 20mA when the output voltage is as low as 0.2V. 0.2 Dynamic Output Impedance The MAX8515A features an initial output accuracy of Space-Saving 5-Pin SC70 or SOT23 Packages 0.5% at +25C and 1% from -40C to +85C and provides the output voltage regulation function for isolated DC-to- DC converters. The MAX8515 features initial output accuracy of 1% at +25C and 1.8% from -40C to +85C and can provide an output OVP function for isolated DC- Ordering Information to-DC converters. High open-loop bandwidth allows PART TEMP RANGE PIN-PACKAGE design of high-bandwidth DC-to-DC converters. MAX8515AEXK-T -40C to +85C 5 SC70-5 Low-cost, low-dropout linear regulators can be designed with the MAX8515A/MAX8515 and an external NPN tran- MAX8515AEZK-T -40C to +85C 5 Thin SOT23-5 sistor for cost-conscious applications that do not require MAX8515EXK-T -40C to +85C 5 SC70-5 overcurrent, short-circuit, or overtemperature protection. MAX8515EZK-T -40C to +85C 5 Thin SOT23-5 The MAX8515/MAX8515A are available in space-saving 5-pin SC70 and SOT23 packages and are specified over the -40C to +85C extended temperature range. An eval- uation kit is available to speed designs. Functional Diagram appears at end of data sheet. Selector Guide appears at end of data sheet. Applications Isolated DC-to-DC Converters Network, Telecom, and Cellular Base Station Power Supplies Typical Operating Circuit Low-Dropout Linear Regulators INPUT SUPPLY INPUT Shunt Regulator 1.7V TO 28V 1.7V TO 18V Adjustable Voltage Reference PRIMARY SIDE PWM CONVERTER Pin Configuration CONTROL VOLTAGE TOP VIEW IN OUT PGND15FB MAX8515A MAX8515A MAX8515 GND 2 MAX8515 ISOLATED DC-DC PGND CONVERTER GND FB OUTPUT OUT34 IN (DOWN TO 0.6V) SC7O/THIN SOT23 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. x EVALUATION KIT AVAILABLE N 2 I . P 1 - 5 m mWide-Input 0.6V Shunt Regulators for Isolated DC-to-DC Converters ABSOLUTE MAXIMUM RATINGS IN to GND...............................................................-0.3V to +30V Operating Temperature Range ...........................-40C to +85C OUT to GND ...........................................................-0.3V to +20V Junction Temperature Range ............................-40C to +150C FB to GND .................-0.3V to the lower of 5.5V and (V +0.3V) Storage Temperature Range .............................-65C to +150C IN PGND to GND .......................................................-0.3V to +0.3V Lead Temperature (soldering, 10s) .................................+300C Continuous Power Dissipation (T =+70C) A 5-Pin SC70 (derate 3.1mW/C above +70C)...........246.9mW 5-Pin Thin SOT23 (derate 9.1mW/C above +70C)....727mW 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 = 3.3V, OUT = FB, I = 5mA, T = -40C to +85C, unless otherwise noted. Typical values are at T = +25C.) (Note 1) IN OUT A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS IN IN Voltage Range V 1.7 28 V IN I = 0.3mA 0.5 1 OUT IN Supply Current I V = 2V to 28V mA IN IN I = 10mA 2.5 4 OUT FB MAX8515AE K 0.597 0.6 0.603 T = +25C A MAX8515E K 0.594 0.6 0.606 MAX8515AE K 0.595 0.6 0.605 FB Threshold Accuracy T = 0C to +85C V A MAX8515E K 0.592 0.6 0.608 MAX8515AE K 0.594 0.6 0.606 T = -40C to +85C A MAX8515E K 0.589 0.6 0.608 FB Load Regulation I = 1mA to 20mA 3.8 6 mV OUT V = 2V to 28V 0.2 1 IN FB Line Regulation mV V = 1.7V to 28V 1.5 IN FB Output Voltage Regulation V = 0.2V to 18V, I = 1mA 0.2 1 mV OUT OUT FB Input Bias Current I V = 28V -0.1 0.02 +0.1 A FB(BIAS) IN OUT OUT Voltage Range V 0.2 18 V OUT Maximum Output Current I V = 0.2V, V = 2V, V = 0.63V 20 mA OUT(MAX) OUT IN FB T = +25C 0.001 0.1 V = 28V, V = 18V, A IN OUT Output Leakage Current I A OUT(LEAK) V = 0V FB T = +85C 0.03 A Dynamic Output Impedance Z I = 1mA to 20mA, f <1kHz 0.2 0.32 OUT OUT Note 1: Devices are production tested at T = +25C, limits over temperature are guaranteed by design. A 2 MAX8515A/MAX8515