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TPS5420MDREP: A Buck Switching Regulator

We already know that a DC-to-DC converter helps in converting power or current coming directly into the corresponding value. However, for a DC-to-DC converter to work effectively, it sometimes needs to work with a DC-to-DC voltage regulator.

The reason is not far-fetched from the fact that the entire current conversion process could be fraught with some power shortchanges, which may end up halting the procedure. With the voltage regulator in place, it could be much easier to scale the current conversion process.

According to Digi-Key, a DC-to-DC voltage regulator can also be called a DC-to-DC switching regulator. It is to be used with devices or applications that require a higher stabilization of the DC input voltage.

The regulator is also greatly needed with the applications that require a transformation thereof from the input voltage to the corresponding value of the output voltage, in a different magnitude.

Introducing TPS5420MDREP as a Buck Switching Regulator

TPS5420MDREP is a buck switching regulator and from what we explained in the last paragraph, its functionality might be a bit different from what a DC-to-DC switching regulator does.

STMicroelectronics explains that a Buck Switching Regulator, also known as a buck converter or a buck regulator, is a type of DC-to-DC converter. The primary use is to provide a higher output voltage than the input voltage does.

One of the highlights of this converter is how it aids power or current “step-down.” In a case where the current or voltage is excessive and could potentially harm the device, it makes sense to have something to stop that from happening.

What Makes TPS5420MDREP’s Buck Switching Regulator Different?


If you are looking to buy any product (including a power or current converting device), one of the things to consider is the unique features. Does the product have something better to offer than its competitors offer? If so, what is the relevance of those features to how the product functions?

TPS5420MDREP is indeed, a bit different from some of the other DC-to-DC converters out there because of the following features:

1. It has a Controlled Baseline

By “controlled baseline,” the manufacturer means that there might no need to look for external components to use with the TPS5420MDREP.

The controlled baseline offers this regulator a one fabrication site, and the capabilities can also be assembled and tested on the same site.

2. TPS5420MDREP Supports Internal Compensation

Despite the fact that TPS5420MDREP uses a controlled baseline design, there is a chance that the designer may want to “look elsewhere” for additional components.

It is for this purpose that the manufacturer thought it wise to add a feature to restrict that. The feature is called an internal compensation. It is attached to the TPS5420MDREP’s feedback loop and the functions include:

3. It Reduces Design Complexities

The internal compensation goes a long way to “smoothen the process” of configuring TPS5420MDREP. This smoothening is a part of the efforts to reduce the complexities that could come with designing or configuring the target applications.

4. Zero Support for External Components

External or additional components or parts could be required and that would mean faulting the controlled baseline for TPS5420MDREP.

In this instance, TPS5420MDREP’s internal compensation feature helps to minimize the need for external parts for the converter.

5. TPS5420MDREP Offers Higher Voltage Regulator

Though the core function of a buck switching regulator is to provide a higher output voltage, that of TPS5420MDREP does it better.

Here are some of the reasons why it is so:

Higher Voltage Conversion with Resistance Balance

Converting current from a higher voltage can sometimes lead to over-voltage or under-voltage. In any of those instances, some of the voltages might be lost in the process and pose a resistance.

However, it is tackled with the balanced offered through TPS5420MDREP’s high-output-current PWM converter, which integrates a low-resistance, high-side, N-Channel MOSFET.

Besides the balanced offered via the MOSFET, TPS5420MDREP also helps in tightening the voltage conversion process. This it does through the high-performance voltage error amplifier. The amplifier works by providing a “tight voltage regulation accuracy under transient conditions.” The provision made here helps TPS5420MDREP to work even under the “tightest of conditions.”

TPS5420MDREP also offers the following:

Voltage Feed-Forward Circuit

The function of this circuit is to improve the device’s transient response.

Slow-Start Circuit

This is an internally-set circuit that limits the inrush currents (the rate at which current comes into the TPS5420MDREP).

We think this is a great feature because it will help prevent TPS5420MDREP from going overboard when the current inflow is beyond the rating.

Undervoltage-Lockout Circuit

This is a dedicated circuit that first, helps to prevent the TPS5420MDREP from going below the rated voltage – which is undervoltage.

It also plays a role in ensuring that the TPS5420MDREP regulator doesn’t boot or function until the undervoltage issue is tackled. It is for this reason that the undervoltage-lockout circuit prevents TPS5420MDREP from “starting up” until the “input voltage reaches 5.5 V.”

Efficiency and Accuracy

Besides regulating the output and input voltages, TPS5420MDREP also has one other function – to ensure that the regulation is accuracy.

First, it offers a 1.5% initial accuracy via the adjustable down feature with a 1.22V. This helps the regulator to maximize the wide output voltage range.

As for the efficiency, TPS5420MDREP assures that with the 95% efficiency rating, which is enabled by the 110-mΩ Integrated MOSFET Switch.

As a way of increasing the operating capacity, TPS5420MDREP supports a wide input voltage range, which is between a minimum of 5.5 volts and a maximum of 35 volts.

TPS5420MDREP Offers System Protection

It is now possible to increase the protective measures for this buck switching regulator using the several protective features. The most outstanding is the thermal shutdown, that shuts down the system. There is also the overcurrent limiting feature that prevents the system from further operations when it exceeds the rated voltage.


TPS5420MDREP is a buck switching regulator with several protective features, excellent current conversion properties and a wide range of components (including the fixed 500-kHz switching frequency for small size filter) that make the entire process seamless.