Review of LTM4619IV#PBF’s DC/DC Converter with Non-Isolated PoL Module

LTM4619IV#PBF is a dual 4A, or single 8A step-down DC/DC µModule. Thus, the designation as a micromodule µModule allows for the flexible configuration of the converter. Rest assured that if you are looking for one of the best DC/DC converters in the market, LTM4619IV#PBF will be among the first on the list.

This blog post explains the major things you need to know about how this converter works and every other thing in-between.

The Focus is on Power Supply Conversion

At the core of LTM4619IV#PBF’s operation as a DC/DC converter is the flexible conversion of power supply. Before now, converting electrical power into other supported variants like a more compatible output level is not easy to do.

As a power supply, which is the broader function, LTM4619IV#PBF is now able to convert electrical power gotten from one source to other suitable variants. It is prioritized if the converted power supply is to be used for specific purposes, such as making a mechanic or physical connection within an application to a Printed Circuit Board (PCB).

Coming down further, LTM4619IV#PBF doubles as a non-isolated PoL module, which is one of the major modules used for power conversion.

According to Digi-Key, a non-isolated PoL module is a type of device (preferably a DC/DC converter) used to convert or change a direct current voltage input level to a corresponding direct current voltage output level.

LTM4619IV#PBF has a Fast Transient Response

The process of sending the converted power supply from one point to the other is one of the highpoints of LTM4619IV#PBF’s functionalities. In this instance, it offers a faster or more robust transient response – a process that enables the higher switching capability of the converter to respond to the line and load changes. It handles all these perfectly without sacrificing the stability.

Besides, LTM4619IV#PBF offers a more balanced mode operation, offered in the form of a current mode control. The excellent mode control offered through this process allows for either the pulse-skipping mode or the Burst Mode operation to facilitate light load operations.

Power Conversion Components are Supported

LTM4619IV#PBF supports a variety of power conversion-centric support components. Examples of these components are:

  • Switching controller
  • Inductor
  • Power FETs

Current Sharing

For one reason or the other, the current might not be intertwined and that creates the opening for power conversion imbalance.

As a way of balancing it, LTM4619IV#PBF uses a parallel current sharing model to straighten out the process.

Besides, it also supports frequency synchronization and output voltage tracking. These two are used to enable supply rail sequencing on the device.

High-Efficiency Design

Designed and optimized for the highest-performance possible; LTM4619IV#PBF uses its highly-optimized design to deliver a dual 180˚ Out-of-Phase Outputs. These outputs are then able to work with a 4A continuous current (of 5A peak) for each output current.

Space Maximization

Without leaving any space to lay “fallow,” LTM4619IV#PBF maximizes all the spaces available. An ideal exemplification of this is the low-profile package measuring 2.28mm. It allows for the utilization of the unused space on the PC board’s bottom to configure the high-density boards, while using the Point-of-Load (PoL) regulation to keep the performance in check.

Improved Fault Protection Features

Fault detection is one important mechanism that can make all the difference in an Integrated Circuit (IC). The ability to detect potential threats and fixing the same in real-time is great and we are pleased to see some of the improved features on LTM4619IV#PBF.

The list of fault protection features on this DC/DC converter includes:

1. Foldback Current Limit

This is a type of fault protection feature that prevents short-circuiting from taking dominance in this DC/DC converter.

2. Overvoltage Protection

Sometimes, circuits can go beyond or above the recommended or rated voltages. That is why LTM4619IV#PBF uses an overvoltage protection feature to regulate the circuit’s function when it is overloaded with voltage supply.

3. Overcurrent Protection

Just like the overvoltage protection, the overcurrent protection protects this DC/DC converter from damages caused because of an excessive supply of current.

The Concept of Non-Isolated PoL Module

LTM4619IV#PBF is described as a “non-isolated PoL” DC/DC converter – but what does it really mean?

When we talk about isolation in terms of DC/DC power conversion, the focus is usually on the use of a “galvanic isolation” method to prevent any direct conduction path between the two parts of the circuit.

By cutting off the metallic connection between these two circuit parts, there is now a barrier between them. That barrier goes further to serve security purposes, especially in the sense of preventing inordinate power dissipation.

The major upside to using a non-isolated power converter like LTM4619IV#PBF is that it cuts down the bureaucracies – including improving the circuit’s efficiency.

The non-isolated power converter also maximizes more circuit board spaces because it doesn’t make any special separation of the circuit parts, which could have required more spaces.

Due to the lesser space usage, the non-isolated power converter also attracts a lower Bill of Material (BOM) cost and the optimization can be completed in the shortest time possible.

However, you would be sacrificing a couple of things in the process. For example, a non-isolated power converter like LTM4619IV#PBF doesn’t isolate or separate the circuit parts. That could trigger safety concerns, especially when you consider that the non-separated parts might be susceptible to causing electric shocks.

Nevertheless, if you can manage that, using a non-isolated power converter might be a great idea for power supply distribution in a circuit. According to CUI INC., using a non-isolated PoL module can make the following differences:

4. Load Proximity

It is called a Point-of-Load (PoL) module for a reason. The placement of the non-isolated DC/DC converters to the load helps to reduce the effects that come with passing the converted power supply through the transmission lines.

5. Better Transient Performance

The smaller size and the absence of an isolation barrier in the form of a transformer or a pair of opto-couplers helps to improve the converter’s transient performance.


LTM4619IV#PBF makes power conversion simple, thanks to the small size that allows for the proximity to the load. The non-isolation also removes the hassles associated with transmitting the converted power supply.