Description

The MAX857CUA is an IC chip that belongs to the category of Electronic Components. It is a high-efficiency, CMOS, step-up DC-DC switching regulator which is designed for small, low input voltage or battery-powered systems. This device is suitable for 3.3V to 5V step-up conversion, palmtop computers, portable data-collection equipment, personal data communicators/computers, medical instrumentation, 2-cell & 3-cell battery-operated equipment, and glucose meters. The MAX857CUA regulator accepts a positive input voltage between 0.8V and VOUT and converts it to a higher, pin-selectable output voltage of 3.3V or 5V. It combines ultra-low quiescent supply current and high efficiency to give maximum battery life. Typical efficiencies are greater than 85%, and typical quiescent supply current is 25µA (1µA in shutdown).

Specifications and Features

• Input Supply Voltage: 0.8V to 6.0V
• Start-Up Supply Voltage: 0.8V Typ
• Efficiency at 100mA: 85%
• Quiescent Current: 25µA
• Shutdown Mode: 1µA
• Switch-Current Limits: 125mA and 500mA
• Switching Frequency: Up to 500kHz
• Reference Tolerance Over Temperature: ±1.5%
• Low-Battery Detector (LBI/LBO)
• Packages: 8-Pin SO and µMAX

Application Scenarios

The MAX857CUA is suitable for various electronic devices that require step-up DC-DC switching regulators, such as palmtop computers, portable data-collection equipment, personal data communicators/computers, medical instrumentation, 2-cell & 3-cell battery-operated equipment, and glucose meters.

Comparison

• High efficiency with ultra-low quiescent supply current
• Pin-selectable output voltage of 3.3V or 5V
• Switching frequency up to 500kHz
• Low-battery detector
• Available in 8-pin SO and µMAX packages

• The MAX856/MAX858 have lower peak inductor current limits compared to the MAX857/MAX859.