1 Features

• Wide Input Voltage Range: 4.5 V to 42 V
• Internally Compensated Voltage Mode Control
• Stable with Low ESR Ceramic Capacitors
• 200 mΩ N-Channel MOSFET
• Output Voltage Options:
  -ADJ (Outputs as Low as 1.285 V)
  -5.0 (Output Fixed to 5 V)
• ±1.5% Feedback Reference Accuracy
• Switching Frequency of 500 kHz
• –40°C to 125°C Operating Junction Temperature Range
• Precision Enable Pin
• Integrated Boot-Strap Diode
• Integrated Soft-Start
• Fully WEBENCH® Enabled
• Step-Down and Inverting Buck-Boost Applications
• LM22675Q is an Automotive Grade Product
  that is AEC-Q100 Grade 1 Qualified (–40°C to +125°C Operating Junction Temperature)
• SO PowerPAD-8 (Exposed Pad) Package

2 Applications

• Industrial Control
• Telecom and Datacom Systems
• Embedded Systems
• Conversions from Standard 24 V, 12 V and 5 V Input Rails

3 Description

The LM22675 switching regulator provides all of the functions necessary to implement an efficient high voltage step-down (buck) regulator using a minimum of external components. This easy to use regulator incorporates a 42 V N-channel MOSFET switch capable of providing up to 1 A of load current. Excellent line and load regulation along with high efficiency (> 90%) are featured. Voltage mode control offers short minimum on-time, allowing the widest ratio between input and output voltages. Internal loop compensation means that the user is free from the tedious task of calculating the loop compensation components. Fixed 5 V output and adjustable output voltage options are available. A switching frequency of 500 kHz allows for small external components and good transient response. A precision enable input allows simplification of regulator control and system power sequencing. In shutdown mode the regulator draws only 25 µA (typ). Built in soft-start (500 µs, typ) saves external components. The LM22675 also has built in thermal shutdown, and current limiting to protect against accidental overloads.

The LM22675 is a member of Texas Instruments' SIMPLE SWITCHER® family. The SIMPLE SWITCHER concept provides for an easy to use complete design using a minimum number of external components and the TI WEBENCH design tool. TI's WEBENCH tool includes features such as external component calculation, electrical simulation, thermal simulation, and Build-It boards for easy design-in.

1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Application Schematic