LT3028 ELECTRICAL CHARACTERISTICSNote 4: Operating conditions are limited by maximum junction Note 7: GND pin current is tested with VIN = 2.44V and a current source temperature. The regulated output voltage specification will not apply for load. This means the device is tested while operating in its dropout region all possible combinations of input voltage and output current. When or at the minimum input voltage specification. This is the worst-case GND operating at maximum input voltage, the output current range must be pin current. The GND pin current will decrease slightly at higher input limited. When operating at maximum output current, the input voltage voltages. Total GND pin current is equal to the sum of GND pin currents range must be limited. from Output 1 and Output 2. Note 5: To satisfy requirements for minimum input voltage, the LT3028 is Note 8: ADJ1 and ADJ2 pin bias current flows into the pin. tested and specified for these conditions with an external resistor divider Note 9: SHDN1 and SHDN2 pin current flows into the pin. (two 250k resistors) for an output voltage of 2.44V. The external resistor Note 10: For the LT3028 dropout voltage will be limited by the minimum divider will add a 5µA DC load on the output. input voltage specification under some output voltage/load conditions. See Note 6: Dropout voltage is the minimum input to output voltage differential the curve of Minimum Input Voltage in the Typical Performance needed to maintain regulation at a specified output current. In dropout, the Characteristics. output voltage will be equal to: VIN – VDROPOUT. WUTYPICAL PERFOR A CE CHARACTERISTICSOutput 2Output 2Typical Dropout VoltageGuaranteed Dropout VoltageOutput 2 Dropout Voltage 500 500 500 = TEST POINTS 450 450 450 400 400 400 350 T T 350 J = 125°C 350 J ≤ 125°C IL = 100mA 300 300 300 250 250 TJ ≤ 25°C 250 IL = 50mA 200 TJ = 25°C 200 200 150 150 150 IL = 10mA DROPOUT VOLTAGE (mV) DROPOUT VOLTAGE (mV) DROPOUT VOLTAGE (mV) 100 100 100 IL = 1mA 50 50 50 0 0 0 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100 –50 –25 0 25 50 75 100 125 OUTPUT CURRENT (mA) OUTPUT CURRENT (mA) TEMPERATURE (°C) 3028 G01 3028 G02 3028 G03 Output 1Output 1Typical Dropout VoltageGuaranteed Dropout VoltageOutput 1 Dropout Voltage 500 500 500 = TEST POINTS 450 450 450 IL = 500mA 400 400 400 T I J = 125°C T L = 250mA J ≤ 125°C 350 350 350 IL = 100mA 300 300 300 T I J ≤ 25°C L = 50mA 250 250 250 TJ = 25°C 200 200 200 150 150 150 DROPOUT VOLTAGE (mV) DROPOUT VOLTAGE (mV) 100 100 100 IL = 1mA 50 50 I GUARANTEED DROPOUT VOLTAGE (mV) 50 L = 10mA 0 0 0 0 50 100 150 200 250 300 350 400 450 500 0 50 100 150 200 250 300 350 400 450 500 –50 –25 0 25 50 75 100 125 OUTPUT CURRENT (mA) OUTPUT CURRENT (mA) TEMPERATURE (°C) 3028 G04 3028 G05 3028 G06 3028f 4