LT3091 elecTrical characTerisTicsNote 1. Stresses beyond those listed under Absolute Maximum Ratings Note 6. Load regulation is Kelvin sensed at the package. may cause permanent damage to the device. Exposure to any Absolute Note 7. Dropout voltage is the minimum output-to-input voltage Maximum Rating condition for extended periods may affect device differential needed to maintain regulation at a specified output current. In reliability and lifetime. dropout, the output voltage is: VIN + VDROPOUT. Note 2. The LT3091 is tested and specified under pulsed load conditions Note 8. GND pin current is tested with VIN = VOUT(NOMINAL) and a current such that TJ ≅ TA. The LT3091E is guaranteed to meet performance source load. Therefore, the device is tested while operating in dropout. specifications from 0°C to 125°C junction temperature. Specifications over This is the worst-case GND pin current. GND pin current decreases at the –40°C to 125°C operating temperature range are assured by design, higher input voltages. characterization, and correlation with statistical process controls. The Note 9. The SET pin is clamped to OUT with diodes through 12k resistors. LT3091I is guaranteed over the full –40°C to 125°C operating junction These resistors and diodes only carry current under transient overloads or temperature range. The LT3091MP is 100% tested and guaranteed fault conditions. over the full –55°C to 150°C operating junction temperature range. The LT3091H is 100% tested at the 150°C operating junction temperature. Note 10. Positive SHDN pin current flows into the SHDN pin. High junction temperatures degrade operating lifetimes. Operating lifetime Note 11. The SHDN threshold must be met to ensure device operation. is derated at junction temperatures greater than 125°C. Note 12. Output noise decreases by adding a capacitor across the voltage Note 3. Parasitic diodes exist internally between the OUT, SET, ILIM, setting resistor. Adding this capacitor bypasses the voltage setting SHDN, IMONP, IMONN, and GND pins and the IN pin. Do not drive OUT, resistor’s thermal noise as well as the reference current’s noise. Output SET, ILIM, SHDN, IMONP, IMONN, and GND pins more than 0.3V below noise then equals the error amplifier noise (see Applications Information the IN pin during fault conditions. These pins must remain at a voltage section). more positive than IN during normal operation. Note 13. The internal back-up current limit circuitry incorporates foldback Note 4. The LT3091 may go out of regulation if the minimum output protection that decreases current limit for VOUT – VIN ≥ 7V. Some level of current requirement is not satisfied. output current is provided at all VOUT – VIN differential voltages. Please Note 5. Maximum junction temperature limits operating conditions. The consult the Typical Performance Characteristic graph for current limit vs regulated output voltage specification does not apply for all possible VOUT – VIN. combinations of input voltage and output current, primarily due to the Note 14. The current limit programming scale factor is specified while internal current limit foldback which decreases current limit at V the internal backup current limit is not active. Please note that the internal OUT – V current limit has foldback protection for V IN ≥ 7V. If operating at maximum output current, limit the input voltage OUT-to-VIN differentials greater range. If operating at maximum input voltage, limit the output current than 7V. range. Note 15. For positive current monitoring, bias IMONN to ≥ 2V above IMONP. Typical perForMance characTerisTics TJ = 25°C, unless otherwise noted.SET Pin CurrentSET Pin CurrentOffset Voltage (VOUT – VSET) 50.5 2.0 IL = 1mA N = 4726 I 50.4 L = 1mA VOUT = –1.25V 1.5 VOUT = –1.25V 50.3 VIN = –1.9V VIN = –1.9V 1.0 50.2 50.1 0.5 TAGE (mV) 50.0 0 49.9 –0.5 SET PIN CURRENT (µA) 49.8 OFFSET VOL –1.0 49.7 49.6 –1.5 49.5 –2.0 –75 –50 –25 0 25 50 75 100 125 150 49 49.5 50 50.5 51 –75 –50 –25 0 25 50 75 100 125 150 TEMPERATURE (°C) DISTRIBUTION (µA) TEMPERATURE (°C) 3091 G01 3091 G02 3091 G03 3091fa For more information www.linear.com/LT3091 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
