3.3V/5V or Adjustable-Output,Step-Up DC-DC ConvertersMAX856–MAX859ELECTRICAL CHARACTERISTICS (continued) (Circuits of Figure 2, VIN = 2.5V, ILOAD = 0mA, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) –———– – SHDN, 3/5 Input Voltage Low 0.4 V ———– – SHDN, 3/5 Input Voltage High 1.6 V ———– – –———– – SHDN, 3/5, FB, LBI Input Current LBI = 1.5V, FB = 1.5V, SHDN = 0V or 3V, 3/5 = 0V or 3V ±100 nA FB Voltage MAX857/MAX859 1.22 1.25 1.28 V Output Voltage Range MAX857/MAX859, ILOAD = 0mA (Note 3) 2.7 6.0 V Note 2: Supply current from the 3.3V output is measured with an ammeter between the 3.3V output and OUT pin. This current correlates directly with actual battery supply current, but is reduced in value according to the step-up ratio and efficiency. VOUT = 3.47V to keep the internal switch open when measuring the current into the device. Note 3: Minimum value is production tested. Maximum value is guaranteed by design and is not production tested. __________________________________________Typical Operating Characteristics (Circuits of Figure 2, TA = +25°C, unless otherwise noted.) MAX858/MAX859MAX858/MAX859EFFICIENCY vs. OUTPUT CURRENTEFFICIENCY vs. OUTPUT CURRENTVOUT = 3.3VVOUT = 5V 100 100 90 90 MAX856-01 VIN = 2.5V MAX856-02 VIN = 3.3V 80 80 70 70 VIN = 2.0V V 60 IN = 2.5V V 60 V IN = 1.5V IN = 1.5V 50 50 40 40 EFFICIENCY (%) EFFICIENCY (%) 30 30 20 20 10 10 0 0 0.001 0.01 0.1 1 10 100 1000 0.001 0.01 0.1 1 10 100 1000 LOAD CURRENT (mA) LOAD CURRENT (mA) MAX856/MAX857MAX856/MAX857EFFICIENCY vs. OUTPUT CURRENTEFFICIENCY vs. OUTPUT CURRENTVOUT = 5VVOUT = 3.3V 100 100 90 VIN = 3.3V 90 MAX856-03 MAX856-04 VIN = 2.5V 80 80 70 70 VIN = 2.0V VIN = 1.5V 60 60 50 50 VIN = 2.0V 40 40 EFFICIENCY (%) EFFICIENCY (%) 30 VIN = 1.5V 30 20 20 10 10 0 0 0.001 0.01 0.1 1 10 100 1000 0.001 0.01 0.1 1 10 100 1000 LOAD CURRENT (mA) LOAD CURRENT (mA) _______________________________________________________________________________________3