LM2695

High Voltage (30V, 1.25A) Step Down Switching

Regulator

General Description

The LM2695 Step Down Switching Regulator features all of

the functions needed to implement a low cost, efficient, buck

bias regulator capable of supplying 1.25A to the load. This

buck regulator contains a 33V N-Channel Buck Switch, and

is available in the thermally enhanced LLP-10 and TSSOP-

14EP packages. The hysteretic regulation scheme requires

no loop compensation, results in fast load transient re-

sponse, and simplifies circuit implementation. The operating

frequency remains constant with line and load variations due

to the inverse relationship between the input voltage and the

on-time. The current limit detection is set at 1.25A. Additional

features include: VCC under-voltage lockout, thermal shut-

down, gate drive under-voltage lockout, and maximum duty

cycle limiter.

Features

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Integrated 33V, N-Channel buck switch

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Integrated start-up regulator

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Input Voltage Range: 8V to 30V

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No loop compensation required

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Ultra-Fast transient response

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Operating frequency remains constant with load current

and input voltage

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Maximum Duty Cycle Limited During Start-Up

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Adjustable output voltage

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Valley Current Limit At 1.25A

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Precision internal reference

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Low bias current

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Highly efficient operation

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Thermal shutdown

Typical Applications

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High Efficiency Point-Of-Load (POL) Regulator

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Non-Isolated Telecommunication Buck Regulator

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Secondary High Voltage Post Regulator

Package

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LLP-10 (4 mmx4mm)

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TSSOP-14EP

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Exposed Thermal Pad For Improved Heat Dissipation

Basic Step Down Regulator

20170431

January 2006

© 2006 National Semiconductor Corporation

DS201704

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