1. Linear Technology Corporation
Introducing the LTM®4618
26V, 6A Step-Down µModule® Regulator
Dave Quarles Vice President of International Sales

2. Introducing The LTM4618
The LTM4618 is a 4.5V to 26.5V VIN highly efficient step-down µModule regulator capable of delivering 6A of output current.
Purpose of this training:
Explain what is a µModule regulator and its benefits
Provide an in-depth look at the LTM4618
Main features / functionality and benefits / reliability testing
Provide instructions for obtaining design support and additional product information
Welcome to the LTM4618 step-down micro-module regulator product training. This presentation will cover the features, benefits and design support tools available for the LTM4618, a 26V input 6A step-down switching regulator.

3. What is a µModule Regulator?
A Complex Power Solution Becomes…
Simple Again
Product displayed for demonstration purposes only
Linear Technology’s step-down micro-module regulators are complete power systems containing the DC/DC controllers, power switches, inductors, compensation circuitry and a modest amount of input and output bypass capacitance in a single package. This allows what was a complex DC/DC power solution to become simple again.

4. DC/DC Converter Comparison Table
µModule® Regulator
Linear Regulator
Switching Regulator
Switching Controller
High Efficiency Region1 (VOUT vs. VIN)
Wide
Narrow (VOUT ≥ 85% of VIN)
Component Count
Low
Moderate
High
Output Power
Low to High
Low to Mid
Design Effort
PCB Layout Effort
Schematic    
By including the controllers, power MOSFETs, inductors, input and output bypass capacitors and compensation circuitry, the LTM product family simplifies component selection, PCB layout and design-in effort to the level of a comparably feature-rich linear regulator. At the same time, they operate with high efficiency over a wide range of input and output voltage combinations like a switching regulator. Additionally, as many as four micro-module converters may paralleled together for even greater output current capability. Linear Technology’s micro-module regulators present an excellent DC/DC converter solution for engineers seeking the fastest time to market and/or facing limited power design resources. 
1. Defined as supporting 85% efficiency or greater for this comparison

5. LTM4618 Key Features 4.5V to 26.5V input range Up to 6A output current
0.8V to 5V output range
±1.2% VREF Accuracy (-40°C to +125°C)
Up to 96% Efficient
Externally Adj FSW 250kHz – 780kHz
Synchronizable to external clock
Optional Pulse Skip or Burst Mode Operation for high efficiency at light loads
Adjustable soft start
9 x 15 x 4.32mm LGA package
optional
The LTM4618 step-down micro-module regulator delivers up to 6A from an input supply ranging from 4.5V to 26.5V. An accurate output voltage in the range of 0.8V to 5V is determined by a single external resistor. The external clock input supports a uniform switching frequency within the system for noise isolation. Packaged within a 9 x 15 x 4.32mm land grid array package, the LTM4618 is compatible with surface mount reflow techniques and is RoHS compliant.

6. LGA Reliability Combined data for all LTMs in 9 x 15mm LGA
Device Hours
Failures
High Temperature Bake (+150°C) Operating
1,829,581
Life Test (+125°C equivalent)
938,000
Device Cycles
Temp Cycle (-65°C to +150°C)
2,713,500
Thermal Shock (-65°C to +150°C)
1,773,000
Board Mount Temp Cycle (-40°C to +125°C)
548,000
Linear Technology’s LGA packages are thermally efficient, highly reliable enclosures for the components inside the micro-module regulator. This table shows the latest datapoints from ongoing reliability tests. The complete report is available for download at

7. LTM4618 LTSpice Model
Simple to verify using LTspice simulation software available for free!
Pre-built models for virtually all Linear Technology products and many discrete components
Detailed application & Design notes available for download
To assist with the design process, Linear Technology provides LTspice, a free circuit simulation tool with pre-built models of Linear Technology products and standard discrete components.
LTspice is available for download at

8. LTM4618: Summary
For additional information or demo circuits related to the LTM4618 or other µModule® regulator products please visit:
Full suite of design support resources available for free download:
LTspice circuit simulation
LTM product application notes
LTM product design notes
PCB assembly guidelines video
Demo Circuit Gerber files
Look for the Quick Start Link!
For more information on the LTM4618 or any of the more than 30 members of the Linear Technology micro-module product family please visit our website at There the quick start link offers a full suite of design support resources available for free download covering circuit simulation, PCB routing recommendations, thermal analysis, board assembly, rework and more! Thank you for your interest in the LTM V, 6A step-down micro-module regulator.