LT3094 ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the full operatingtemperature range, otherwise specifications are at TA = 25°C. PARAMETERCONDITIONSMINTYPMAX UNITS Minimum Load Current VOUT > –1.5V l 10 µA (Note 16) Thermal Shutdown TJ Rising 167 °C Hysteresis 8 °C Start-Up Time RSET = 49.9k, VOUT(NOM) = –5V, ILOAD = 500mA, CSET = 0.47µF, VIN = –6V, VPGFB = –6V 55 ms RSET = 49.9k, VOUT(NOM) = –5V, ILOAD = 500mA, CSET = 4.7µF, VIN = –6V, VPGFB = –6V 550 ms RSET = 49.9k, VOUT(NOM) = –5V, ILOAD = 500mA, CSET = 4.7µF, VIN = –6V, RPG1 = 50kΩ, 10 ms RPG2 = 700kΩ (with Fast Start-Up to 90% of VOUT) Thermal Regulation 10ms Pulse –0.01 %/W Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 9: OUTS ties directly to OUT. may cause permanent damage to the device. Exposure to any Absolute Note 10: Dropout voltage is the minimum input-to-output differential Maximum Rating condition for extended periods may affect device voltage needed to maintain regulation at a specified output current. The reliability and lifetime. dropout voltage is measured when output is 1% out of regulation. This Note 2: Parasitic diodes exist internally between the EN/UV, ILIM, PG, definition results in a higher dropout voltage compared to hard dropout— PGFB, SET, GND, VIOC, OUTS and OUT pins and the IN pin. Do not drive which is measured when VIN = VOUT(NOMINAL). For output voltages these pins more than 0.3V below the IN pin during a fault condition. between 0V and –1.8V, dropout voltage is limited by the minimum input These pins must remain at a voltage more positive than IN during normal voltage specification. operation. Note 11: GND pin current is tested with VIN = VOUT(NOMINAL) and a current Note 3: The LT3094 is tested and specified under pulse load conditions source load. Therefore, the device is tested while operating in dropout. such that TJ TA. The LT3094E is tested at TA = 25°C and performance This is the worst-case GND pin current. GND pin current decreases at is guaranteed from 0°C to 125°C. Performance of the LT3094E over the higher input voltages. Note that GND pin current does not include SET pin full –40°C and 125°C operating temperature range is assured by design, or ILIM pin current, but they are included in quiescent current. characterization, and correlation with statistical process controls. The Note 12: Adding a capacitor across the SET pin resistor decreases output LT3094I is guaranteed over the full –40°C to 125°C operating junction voltage noise. Adding this capacitor bypasses the SET pin resistor’s temperature range. The LT3094H is 100% tested at the 150°C operating thermal noise as well as the reference current’s noise. The output noise temperature. The LT3094MP is 100% tested and guaranteed over the full then equals the error amplifier noise. Use of a SET pin bypass capacitor –55°C to 150°C operating temperature range. High junction temperatures also increases start-up time. degrade operating lifetimes. Operating lifetime is derated at junction Note 13: The current limit programming scale factor is specified while the temperatures greater than 125°C. internal backup current limit is not active. Note that the internal current Note 4: SET and OUTS pins are clamped using diodes and two 400Ω limit has foldback protection for VOUT – VIN differentials greater than 7V. series resistors. For less than 5ms transients, this clamp circuitry can Note 14: The internal backup current limit circuitry incorporates foldback carry more than the rated current. protection that decreases current limit for VOUT – VIN > 7V. Some level of Note 5: Maximum SET and OUTS pin current requirement must be output current is provided at all VOUT – VIN differential voltages. Consult satisfied. the Typical Performance Characteristics graph for current limit vs VIN – Note 6: Maximum OUT-to-OUTS differential is guaranteed by design. VOUT. Note 7: Maximum junction temperature limits operating conditions. The Note 15: The VIOC amplifier outputs a voltage equal to VIN – VOUT or VIN regulated output voltage specification does not apply for all possible + 1.5V (when VOUT is between 0V and –1.5V). See Block Diagram and combinations of input voltage and output current, especially due to the Applications Information for further information. internal current limit foldback which starts to decrease current limit at Note 16: For output voltages between 0V and –1.5V, the LT3094 requires VOUT – VIN > 7V. If operating at maximum output current, limit the input a 10µA minimum load current for stability. voltage range. If operating at maximum input voltage, limit the output Note 17: MP-Grade is only offered in the DFN package. current range. Note 8: The EN/UV pin threshold must be met to ensure device operation. Rev. B 6 For more information www.analog.com Document Outline Features Applications Typical Application Description 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