LT3692A elecTrical characTerisTicsThe l denotes the specifications which apply over the full operatingtemperature range, otherwise specifications are at TA = 25°C. VVIN1/2 = 15V unless otherwise specified. (Note 3) PARAMETERCONDITIONSMINTYPMAXUNITS Minimum Boost for 100% DC Ch 1/2 (Note 9) 1.6 2.2 2.6 V IND + VOUT Current Ch 1/2 VVOUT1/2 = 0V 1.5 5 µA VVOUT1/2 = 5V 0.5 5 µA ILIM1/2 Reference Current VILIM = 0V l 10 12 16 µA IND to VOUT Maximum Current Ch 1/2 VILIM1/2 = 0V, VVOUT = 1V (Note 10) 0.8 1.8 2.6 A VILIM1/2 = 0V, VVOUT = 5V (Note 10) 1.25 2 3.0 A VILIM1/2 = 0.5V, VVOUT = 1V (Note 10) 1.4 2.2 3.6 A VILIM1/2 = 0.5V, VVOUT = 5V (Note 10) 1.8 2.6 3.8 A VILIM1/2 = 1.5V, VVOUT = 1V (Note 10) l 3.7 4.6 5.8 A VILIM1/2 = 1.5V, VVOUT = 5V (Note 10) l 3.7 4.6 5.8 A Switch Leakage Current Ch 1/2 VSW1/2 = 0V l 1 10 µA Switch Saturation Voltage Ch 1/2 ISW1/2 = 500mA, VBST1/2 = 18V 100 mV ISW1/2 = 3A, VBST1/2 = 18V 300 mV Boost Current Ch 1/2 ISW1/2 = 500mA, VBST1/2 = 8V 7 13 40 mA ISW1/2 = 3A, VBST1/2 = 8V 35 55 85 mA Minimum Boost Voltage Ch1/2 (Note 11) ISW1/2 = 3A, VBST1/2 = 8V 1.6 2.2 3.0 V Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 6: The TJ output voltage represents the temperature at the center may cause permanent damage to the device. Exposure to any Absolute of the die while dissipating quiescent power. Due to switch power Maximum Rating condition for extended periods may affect device dissipation and temperature gradients across the die, the TJ output reliability and lifetime. voltage measurement does not guarantee that absolute maximum junction Note 2: Absolute Maximum Voltage at V temperature will not be exceeded. IN1/2 and SHDN1/2 pins is 60V for nonrepetitive 1 second transients and 40V for continuous operation. Note 7: An internal power on reset (POR) latch is set on the positive Note 3: The LT3692AEUH/LT3692AEFE is guaranteed to meet performance transition of the SHDN1/2 pin through its threshold, thermal shutdown or specifications from 0°C to 125°C junction temperature. Specifications over overvoltage lockout. The output of the latch activates current sources on the –40°C to 125°C operating junction temperature range are assured by each SS pin which typically sink 400µA and discharge the SS capacitor. design, characterization and correlation with statistical process controls. The latch is reset when both SS pins are driven below the soft-start POR The LT3692AIUH/LT3692AIFE is guaranteed over the full –40°C to 125°C threshold or the SHDN pin is taken below its threshold. operating junction temperature range. The LT3692AHUH/LT3692AHFE is Note 8: The threshold is expressed as a percentage of the feedback guaranteed over the full –40°C to 150°C operating junction temperature reference voltage for the channel. range. High junction temperatures degrade operating lifetimes. Operating Note 9: To enhance dropout operation, the output switch will be turned off lifetime is derated at junction temperatures greater than 125°C. for the minimum off-time only when the voltage across the boost capacitor Note 4: VIN undervoltage lockout is defined as the voltage which the VIN drops below the minimum boost for 100% duty cycle threshold. pin must exceed for operation. The threshold guarantees that internal bias Note 10: The IND to VOUT maximum current is defined as the value of lines are regulated and switching frequency is constant. Actual minimum current flowing from the IND pin to the VOUT pin which resets the switch input voltage to maintain a regulated output will depend upon output latch when the VC pin is at its high clamp. voltage and load current. See the Applications Information section. Note 11: This is the minimum voltage across the boost capacitor needed Note 5: VIN overvoltage lockout is defined as the voltage when exceeded to guarantee full saturation of the internal power switch. halts converter operation. See the Applications Information section. 3692afc For more information www.linear.com/3692A 5 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Applications Information Typical Applications Package Description Revision History Typical Application Related Parts