MAX859 Datasheet | Maxim Integrated

Description The MAX856- MAX859 are high-efficiency, CMOS, stepup, DC-DC switching regulators for small, low input volt age or battery-powered systems. The MAX856/MAX858 accept a positive input voltage between 0.8V and V OUT and convert it to a higher, pin-selectable output voltage of 3.3V or 5V. The MAX857/MAX859 adjustable versions accept 0.8V to 6.0V input voltages and generate higher adjustable output voltages in the 2.7V to 6.0V range. Typical efficiencies are greater than 85%. Typical quies cent supply current is 25µA (1µA in shutdown). The MAX856- MAX859 bine ultra-low quiescent supply current and high efficiency to give maximum battery life. An internal MOSFET power transistor permits high switching frequencies. This benefit, bined with internally set peak inductor current limits, permits the use of small, low-cost inductors. The MAX856/MAX857 have a 500m A peak inductor current limit. The MAX858/MAX859 have a 125m A peak inductor current limit. MAX856- MAX859 ______________Ordering Information PART MAX856CSA MAX856CUA MAX856C/D MAX856ESA MAX856MJA MAX857CSA MAX857CUA MAX857C/D MAX857ESA MAX857MJA TEMP. RANGE 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -55°C to +125°C 0°C to +70°C 0°C to +70°C 0°C to +70°C -40°C to +85°C -55°C to +125°C PIN-PACKAGE 8 SO 8 µMAX Dice- 8 SO 8 CERDIP† 8 SO 8 µMAX Dice- 8 SO 8 CERDIP† ________________________Applications 3.3V to 5V Step-Up Conversion Palmtop puters Portable Data-Collection Equipment Personal Data municators/puters Medical Instrumentation 2-Cell & 3-Cell Battery-Operated Equipment Glucose Meters __________Typical Operating Circuit INPUT 0.8V TO VOUT Ordering Information continued at end of data sheet. - Dice are tested at TA = +25°C only. † Contact factory for availability. __________________Pin Configuration TOP VIEW 47µH OUTPUT 5V AT 100m A OR 3.3V AT 125m A 68µF SHDN 3/5 REF 1 2 3 8 7 LX GND OUT LBI ON/OFF SHDN LX 1N5817 MAX856 MAX858 6 5 LBO 4 MAX856 3V/5V SELECT LOW-BATTERY DETECTOR INPUT 3/5...