link to page 2 LTM8078 ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the specified operatinginternal temperature range, otherwise specifications are at TA = 25°C. VIN1 = VIN2 = 12V, RUN = 2V unless otherwise noted (Note 2). PARAMETERCONDITIONSMINTYPMAXUNITS Minimum VIN1 Input Voltage l 3.0 V Minimum VIN2 Input Voltage VIN1 = 3V l 2.0 V Output DC Voltage FBn Open 0.8 V FBn = 21.5kΩ 10 V Maximum Output DC Current (Note 3) 2.5 A Quiescent Current into VINn RUN = 0V 2 4 μA BIAS = 5V, SYNC = 0V, No Load 60 µA BIAS = 5V, SYNC = 3.3V, No Load 10 mA Current into BIAS RUN = 0V, BIAS = 5V 1 μA BIAS = 5V, SYNC = 3.3V, No Load 7 mA Line Regulation 5V < VINn <40V, IOUTn = 0.5A 0.1 % Load Regulation 12VINn, 0.1A < IOUTn < 2A 0.2 % Output RMS Ripple 3.3VOUTn 10 mV FBn Voltage 792 800 808 mV l 784 816 mV Current out of FBn VOUTn = 1V, FBn = 0V 4 µA Minimum BIAS for Proper Operation 3.2 V Switching Frequency RT = 113kΩ 300 kHz RT = 30.9kΩ 1 MHz RT = 7.15kΩ 3 MHz RUN Threshold 0.74 V RUN Input Current RUN = 0V 1 μA PGn Threshold at FBn FBn Rising 740 mV FBn Falling 860 mV PGn Output Sink Current PGn = 0.1V 100 μA CLKOUT VOL 0 V CLKOUT VOH 3.3 V SYNC Input High Threshold 1.5 V SYNC Input Low Threshold 0.8 V SYNC Threshold to Enable Spread Spectrum 2.8 4 V SYNC Current SYNC = 6V 65 μA TRSSn Source Current TRSSn = 0V 2 μA TRSSn Pull-Down Resistance Fault Condition, TRSSn = 0.1V 170 Ω Note 1: Stresses beyond those listed under Absolute Maximum Ratings The LTM8078I is guaranteed to meet specifications over the full –40°C may cause permanent damage to the device. Exposure to any Absolute to 125°C internal operating temperature range. Note that the maximum Maximum Rating condition for extended periods may affect device internal temperature is determined by specific operating conditions in reliability and lifetime. conjunction with board layout, the rated package thermal resistance and Note 2: The LTM8078E is guaranteed to meet performance specifications other environmental factors. from 0°C to 125°C internal. Specifications over the full –40°C to Note 3: The maximum current out of either channel may be limited by the 125°C internal operating temperature range are assured by design, internal temperature of the LTM8078. See output current derating curves characterization and correlation with statistical process controls. for different VIN, VOUT and TA. Rev. A For more information www.analog.com 3 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Application Package Description Revision History Package Photograph Related Parts