MAX756CPA-IC

The MAX756/MAX757 are CMOS step-up DC-DC switching regulators for small, low input voltage or battery-powered systems. The MAX756 accepts a positive input voltage down to 0.7V and converts to a higher pin selectable output voltage or 5V.This an adjustable version that accepts an input voltage down to 0.7V and generates a higher adjustable output voltage in the range from to 5.5V. Typical full-load efficiencies for the MAX756/MAX757 are greater than 87%. The MAX756/MAX757 provide three improvements over previous devices. Physical size is reduced--the high switching frequencies (up to 0.5MHz) made possible by MOSFET power transistors allow for tiny (<5mm diameter) surface-mount magnetics. Efficiency is improved 87% (10% better than with low-voltage regulators fabricated in bipolar technology). Supply current is reduced 60µA by CMOS construction and a unique constant-off-time pulse-frequency modulation control scheme.