Fnirsi DPS-150 Compact and Portable Power Supply and Converter

Compact power supplies are becoming increasingly popular among electronics enthusiasts, makers, and professionals. These devices provide stable, adjustable power outputs in a portable form factor, making them ideal for various applications, from prototyping circuits to powering small gadgets. They are especially useful when fixed-voltage power supplies—such as those from old laptops, power banks, or other power adapters—are already available.

In this review, we explore the features, performance, and value of the Fnirsi DPS-150 mini power supply unit.

Two Options: Converter or Complete PSU

There are two versions of this product available:
1. DPS-150PD – complete kit: Includes a 100W PD GaN power adapter (EU) and a USB-C cable.
2. DPS-150 – DC power converter only: Does not include a mains adapter.

The DPS-150 (converter-only version) is particularly useful for users who already own a compatible fixed-voltage power supply, such as:
 

• A laptop power adapter
• A mobile phone charger
• A tablet power supply unit
• A power bank

Specifications & Overview

A power system using the DPS150 consists of two different modules:

1. DPS150 Programmable DC Power Converter (Figure 1)
2. Mains Adapter (e.g., a mobile charger, power bank, laptop PSU, or the included 100W PD GaN power adapter) (Figure 2)

This modular design allows flexibility, enabling users to integrate the DPS-150 into their existing power supply setup or use the complete kit for an all-in-one solution.

 

Features of the DPS-150 Power System

DPS-150 Programmable DC Power Converter

The power converter offers the following performance specifications:
 

Specification	Value
Input Voltage	5 – 32 V DC
Input Current	100 mA – 5 A
Output Voltage	0 – 30 V
Output Current	0 – 5 A
Output Power	0 – 150 W
Input Sources	PD fast charger, QC fast charger, power bank, DC power adapters
Operating Temperature	0 – 40°C
Load Regulation	0.49%
Full Load Efficiency	96.3%
Display	2.8-inch (320 × 240)
Dimensions	106 × 76 × 28 mm
Weight	178 g

 

Fixed-Voltage Power Supply Options

To provide the input voltage (5 – 32V) required for the DPS-150, several power supply options are available:

100W PD GaN Power Adapter (Included in the Complete Kit)
This power adapter, included in the DPS-150PD kit, offers the following features:
 

Specification	Value
Model	CH100G01
Input Voltage	100-240V AC, 50/60Hz
Power Output Ports
USB-A	5V, 3A
USB-C1/USB-C2 (PD3.0)	5V, 3A / 9V, 3A / 12V, 3A / 15V, 3A / 20V, 5A
PPS (Programmable Power Supply)	3.3 – 20V, 5A (100W max)
Dimensions	65 × 55 × 31.5 mm
Weight	190 g

Alternative Fixed-Voltage Power Supplies
A key advantage of the DPS-150 is its wide input voltage range, allowing it to work with various power sources. For this review, three power supply options were tested:
 

• Laptop Power Supply – 19 V / 3.16 A (60 W)
• Mobile Phone Charger (USB-C Output) – 20 V, 1.5 A (Max. 30 W)
• High-Performance Power Bank

• Standard Power Bank

Figure 3 shows the various input power options tested with the DPS-150.

 

Portable & Battery-Powered Operation

Using a rechargeable power bank provides the additional benefit of independence from the power grid, making the DPS-150 ideal for use in locations without AC power, such as garages, garden sheds, basement labs and fieldwork applications. Additionally, battery operation offers potential-free (isolated) power, effectively eliminating ground loops and improving electrical safety.

Highly Flexible Power

Despite its compact size, the DPS-150 can handle up to 150 W (30 V, 5 A), which is more than sufficient for most applications, whether in the maker scene or for professional users.

One major advantage of this setup is that the main power supply unit can be placed under the table, leaving only the compact power converter unit on the desk, taking up minimal space. Using a rechargeable power bank offers even greater flexibility, allowing for a fully portable power supply with impressive capabilities.

The converter supports USB-C (Quick Charge 3.0) as an input, enhancing its versatility and mobility. It can even be powered by a standard USB port on a PC, though available power will be limited, depending on the port’s specifications. Nonetheless, in crowded workspaces, having access to a variable voltage output can be extremely convenient.

Equipped with a large display, buttons, and an encoder control, the DPS-150 is easy to operate, even one-handed.

The DPS-150 as Lab Power Supply

A voltage range of 0-30 V with up to 5 A of current is typical for lab bench power supplies. The DPS-150 efficiently converts almost any input voltage into a clean, well-regulated output, achieving a conversion efficiency of up to 95%.

For example, using an AC power adapter with a fixed 19 V, 3.16 A (60 W) output, the DPS-150 can generate 3.3 V, 5 V, 12 V, or 18 V, or anything in between, and all up to 3 A.

For the full 30 V output, an input voltage of at least 32 V is required. Old printer power supplies (commonly 32 V / 4 A) can be repurposed for this.

Even a 5V USB charger (1 A max) can provide adjustable voltages between 0 V and nearly 5 V. A portable USB power bank (5 V, 2 A) transforms into a versatile power supply, offering a 0-5 V adjustable output, including the frequently needed 3.3 V for microcontrollers like the ESP32.

Some power banks also provide 12 V outputs with up to 10 A, making the DPS-150 even more versatile. With these, it can deliver nearly 12 V at up to 5 A, which is sufficient for a wide range of electronics projects, battery charging, or modeling.

Precision Testing & Performance Evaluation

For testing, a calibrated HP E2377A multimeter was used. The results confirmed the high precision of the DPS-150 voltage readings:
 

DPS-150 Output (VDC)	HP E2377A Reading (VDC)
0.10	0.102
3.00	3.003
5.00	5.002
10.00	10.00
20.00	20.01
29.95	29.92

The excellent precision is more than sufficient for all practical applications. The measured voltage values are highly accurate, and current readouts were also very precise. The current limiting function works perfectly, even down to the milliamp level.

Load Regulation & Stability

Voltage fluctuations due to load variations were minimal, as confirmed using a high-quality digital multimeter (DMM):

- Voltage drop @ 5 V (idle to 3 A load): < 20 mV

All measurements were conducted using the 4-point Kelvin method, ensuring voltage readings were taken directly at the output connectors to eliminate lead resistance errors.

The load regulation is fast and effective. Figure 4 shows that the voltage peak caused by a load change from 0 A to 2.5 A is less than 20 mV and lasts for under two microseconds.
 

 

Noise Performance & Comparison with Lab Power Supplies

The measured noise level is very acceptable:
 

• Peak-to-peak noise (U_noise_pp): < 4 mV @ 25 V, 3 A load

Of course, noise levels depend on the quality of the external power adapter. For extremely low-noise applications, it is recommended to use batteries as the primary power source.

A comparison between the Fnirsi DPS-150 and a standard linear lab power supply (HP 3612A) shows that ripple values (Vpp and RMS) are comparable. Both units are well-suited for most applications, except for projects that are extremely sensitive to electrical noise.

A test conducted at 5 V and 2.5 A load yielded the following results:
 

Power Supply	V RMS	Vpp
Fnirsi DPS-150	± 350 µV	2.25 mV
HP 3612A	± 450 µV	1.80 mV

Thus, if a standard bench power supply meets the requirements, the compact Fnirsi DPS-150 delivers comparable—or even slightly better—performance in certain cases.

High-Power Testing and Protection

For high-power tests, a set of 50 W resistors was used. The device was tested under the following conditions:
 

• 5 V – 10 A (50 W)
• 15 V – 3 A (45 W)
• 25 V – 2 A (50 W)

All measured values were well within specifications.
 

For an illustrative demonstration, a 12 V, 1.6 A (20 W) halogen lamp was used, with a Li-ion battery pack as the primary power source. Figure 5 shows that the power converter handled this task flawlessly, fully illuminating the halogen lamp at maximum brightness.

PC Software Provides Additional Functionality

Another notable feature is the PC software package, which can be downloaded for free from the Fnirsi website. The program can be launched directly after extraction—no installation is required. Upon starting, the following interface appears (see Fig. 6).
 

The graphical interface is divided into several sections. In the top-left corner, the operating status of the device is displayed visually. Both output voltage and current are plotted over time in a voltage-time graph. Below this, parameters can be adjusted via the PC using either a mouse or keyboard. The values are also represented in circular meters for easy readability. On the right side, the standard output values (Basic Information) are displayed. Alongside the USB communication settings, the selected current and voltage values are shown numerically. Additionally, preset voltage values can be quickly selected and accessed here (Express Data).

Under the "Advanced" tab, additional customization options are available:
 

• Program a custom current or voltage profile
• Define voltage/current steps in selectable increments
• Create arbitrary voltage curves

With these features, the compact DPS-150 becomes a powerful tool for test labs, enabling precision measurement and automated testing applications.
 

 

Wide Range of Applications

Due to its flexibility in power source selection, the DPS-150 is suitable for a wide range of applications, including:
 

• General-purpose testing & teaching in hobbyist and R&D laboratories
• Testing and maintenance of analog and digital electronics
• Fault diagnosis of devices and circuits
• Emergency power supply for field applications
• Quality control and inspection
• Portable "wireless" power supply using power banks or batteries

The ability to operate on battery power makes this power converter highly versatile, allowing it to deliver stable, well-regulated voltage in virtually any location—without requiring a wall outlet.

Pros and Cons

Now, let’s evaluate the strengths and weaknesses of the DPS-150:

Pros:

• Extremely compact and robust design
• High accuracy and reliable performance
• Battery-powered operation for portability
• Easy-to-use interface
• Extensive software integration for remote control & programmable voltage/current curves

Cons:

• Power connector spacing is non-standard (not 19mm apart)
• Only step-down conversion (output voltage must be lower than the input voltage)
• Manual contains unclear or poorly worded instructions
• Overvoltage/overcurrent protection is relatively slow and software-controlled only

Conclusion

The FNIRSI DPS-150 power converter proves to be a valuable tool for both professionals and electronics enthusiasts. It delivers reliable performance, meets expectations with high efficiency, and offers great value for money. One of its standout advantages is its compact and space-saving design, making it an ideal choice for limited workspace environments. With its versatile functionality, precise control, and software integration, the FNIRSI DPS-150 is highly recommended for a variety of applications, whether in professional labs, maker spaces, or DIY electronics workshops.