MC3470N

**The 34700 is a compact, high-efficiency power supply with on-chip power

MOSFETs that features three step-down switching regulators and one low dropout linear regulator. The switching regulators utilize voltage mode control with external compensation, allowing flexibility in optimizing the performance of the 34700 for a given application.**

The 34700 is ideal for space constrained applications where multiple power rails are required and simplicity of design and implementation of the power supply is necessary. Over-voltage, under-voltage, over-current, and over- temperature protection features ensure robust and reliable operation. Fixed switching frequency, internal soft-start, and internal power MOSFETs enable rapid power supply design and development

Features

• Three switching regulators: 2 synchronous and 1 non synchronous
• One low dropout linear regulator
• Output current capability:
• 1.5 A continuous on channel 1
• 1.25 A continuous on channels 2 and 3
• 400 mA continuous on channel 4
• Internal power MOSFETs on all channels
• Voltage feed-forward on channel 1
• ±1.5% Output voltage accuracy on all channels
• Cycle-by-cycle current limit and short-circuit protection
• Fixed 800 kHz switching frequency
• Internal soft-start
• Over-voltage, under-voltage and over-temperature protection
• Open-drain power-good output signal
• Separate active-high enable input for each channel
• Pb-free packaging designated by suffix code EP

Typical Applications:

• Set Top Boxes and Receivers
• Cable Modems
• Networking Cards
• Telecom Line Cards