Top 10 DC/DC converters for compact applications

The DC/DC converter market is forecast to reach $19.8 billion by 2025, up from $8.5 billion in 2019, growing at a compound annual growth rate of 15%, according to a MarketsandMarkets report. DC/DC converters are used in a range of applications from consumer electronics and telecommunications to industrial and medical. The common denominator is the need to develop technologies and architectures that deliver higher efficiency, save board space, and lower total system cost without sacrificing performance. In addition, they often need to operate in harsh or rugged environments. One way that manufacturers are able to meet these challenges is through higher integration and smaller packaging.

Here’s a snapshot of DC/DC converters introduced over the past year that address these challenges. Let’s start with a couple of integrated devices.

Texas Instruments, UCC12050
Earlier this year, Texas Instruments (TI) introduced a high-efficiency isolated DC/DC converter with a new proprietary EMI-optimized integrated transformer technology. TI claims that the 500-mW high-efficiency isolated DC/DC converter offers the industry’s lowest electromagnetic interference (EMI).

In addition, the UCC12050 chip with a 2.65-mm height enables designers to reduce their power solution volume by as much as 80% compared with discrete solutions and 60% compared with power modules, with twice the efficiency of competing devices, according to the company. The UCC12050 provides 5-kVrms reinforced isolation and 1.2-kVrms working voltage to protect against high-voltage spikes in systems such as industrial transport, grid infrastructure, and medical equipment. The reinforced isolation with 8-mm creepage and clearance is used for protection against ground potential differences.

The solution also eliminates external filter components such as low-dropout regulators and ferrite beads normally required to meet EMI certification, which reduces component selection, design time, and cost. The device’s high efficiency coupled with the extended −40°C to 125°C operating temperature range delivers more power in extreme conditions. TI also offers the UCC12040, which provides all of the same benefits with 3-kVrms basic isolation.

Murata Manufacturing Co. Ltd., MYTNA1R86RELA2RA
Another highly integrated and tiny DC/DC converter comes from Murata Manufacturing Co., Ltd. Building on the success of the first-generation product launched last year, Murata has once again claimed the smallest, most efficient, fully integrated 6-A buck regulator with the introduction of the MYTNA1R86RELA2RA DC/DC converter. The device’s footprint is 30% smaller than the nearest competitive solution with a 25% lower profile, measuring 9 × 10.5 × 2.1 mm. Target applications include base stations, networking switches, routers, micro-servers, SSDs, PCIE add-in cards, and high-performance mobile computing platforms.

In addition, the buck regulator needs fewer additional external components to meet stringent transient requirements, making it about 50% smaller than other alternative solutions in the market. The device also delivers more than 10% higher efficiency than competing products, said Murata.

The MYTNA1R86RELA2RA DC/DC converter is designed for two-cell, three-cell, and 12-V point-of-load (POL) applications that call for high efficiency, low profile, and small solution size. The module integrates all passive components, including bulk output capacitance, to meet the exact transient load requirements, which means fewer additional external components are required for most applications, said Murata.

Key features include an input voltage range of 6.0 V–14.4 V and a programmable output of 0.7 V–1.8 V at up to 6 A. The buck regulator’s peak efficiency exceeds 90% for a 12-V input to 1.8-V output.

The device is based on a unique two-stage power conversion architecture developed by the company’s semiconductor division, pSemi, through its acquisition of MIT spin-out Arctic Sand. The benefits of the power architecture include higher efficiency and the size reduction of passive components. The architecture also offers about a 5× reduction in input ripple, lower conducted and radiated EMI emissions, and a wide temperature range of –40°C to 150°C with derating.

Texas Instruments, TPS546D24A
TI also offers a stackable power product, claiming first-of-its-kind stackability of up to four integrated circuits (ICs) — as well as space savings — for maximized power density in high-current FPGA and processor power supplies. The TPS546D24A 40-A SWIFT DC/DC buck converter can deliver up to 160 A of output current at an 85°C ambient temperature, which is 4× more current than competing power ICs, said TI.

The TPS546D24A PMBus buck converter also touts the highest efficiency of any 40-A DC/DC converter, which allows engineers to reduce power loss by 1.5 W in applications such as high-performance data center and enterprise computing, medical, wireless infrastructure, and wired networking.

Thanks to its stackability, the TPS546D24A buck converter can reduce the power supply solution size while optimizing thermal performance. It comes with a PMBus interface that offers a selectable internal compensation network, eliminating as many as six external compensation components from the board and shrinking the overall power supply solution size by more than 10% (or 130 mm2) for higher-current FPGA/application-specific ICs (ASICs) when compared with discrete multiphase controllers.

The device offers a switching frequency of 1.5 MHz, enabling 40 A of current per IC while reducing inductance and capacitance by one-third compared with similar converters. However, high switching frequencies typically have a negative impact on efficiency, which TI mitigates by incorporating a 0.9-mΩ low-side MOSFET, achieving 3.5% higher efficiency than competing DC/DC buck converters.

Other features include a thermal resistance of 8.1°C per watt and 13°C cooler operation than competing DC/DC converters, which helps improve reliability in electronics that operate in hot, harsh environments, including baseband units and automated test equipment.

Analog Devices Inc., LTM4668/LTM4668A
Analog Devices Inc. offers several highly integrated DC/DC power products. A few of the latest are the highly integrated LTM4668 and LTM4668A µModule regulators. These quad-output DC/DC regulators with up to 4.8-A output capability integrate switching controllers, power FETs, inductors, and support components. The high integration helps simplify the design process while reducing power consumption and board space. These devices can be used in applications such as telecom, networking, and industrial applications.

Operating over an input voltage range of 2.7 V to 17 V, the LTM4668 and LTM4668A step-down regulators, housed in 6.25 × 6.25 × 2.1-mm BGA packages, support an output voltage range of 0.6 V to 5.5 V. They also support frequency synchronization, PolyPhase operation, selectable burst-mode operation, 100% duty cycle, and low IQ operation. Their high switching frequency and a current mode architecture enable a very fast transient response to line and load changes without sacrificing stability, said ADI.

TDK Corp., FS Series
Other space savers include TDK Corp.’s FS series of µPOL DC/DC converters. When introduced last year, TDK claimed the FS series as the smallest and highest-power-density POL solutions for applications such as big data, machine learning, artificial intelligence, 5G cells, IoT, and computing enterprise. Instead of using a side-by-side discrete IC and discrete inductor, the FS series integrates the IC and inductor in a small package for space-constrained applications while minimizing the required external components.

The FS series, which measures 3.3 × 3.3 × 1.5 mm, can deliver a high-density solution of 1 W/mm³ while offering 50% less solution size than other products available in its class, according to TDK. The benefits include a lower system solution cost, smaller board size, and reduced bill of materials, PCB, and assembly costs. It operates over a junction temperature range of –40°C to 125°C and is rated for industrial applications.

The µPOL technology was developed by TDK’s group company, Faraday Semi. These solutions incorporate high-performance semiconductors in advanced packaging technologies. These include semiconductor embedded in substrate (SESUB) and advanced electronic components for smaller size and lower-profile devices.

Silanna Semiconductor, SZPL8216A
Another POL and compact DC/DC device family comes from Silanna Semiconductor. The SZPL8216A DC/DC buck converter shrinks PCB space by integrating a DC/DC constant-on-time (COT) controller, output gate drivers, and output power blocks in a 3 × 4-mm QFN package.

With these 12-V synchronous buck converters, designers don’t have to choose between size and power efficiency, according to the company. They deliver up to 12 A with 94% peak efficiency when converting from a nominal 12-V input down to a 0.6-V to 5.5-V output voltage range.

These devices are aimed at providing high power density and efficiency as well as low power loss for demanding applications in enterprise servers, telecommunications, and networking equipment. With a selectable switching frequency from 600 kHz to 1 MHz, the buck converters enable designers to make design decisions to optimize component size versus efficiency. In addition, the ability to operate at 1 MHz allows designers to use a smaller output filter, which further reduces PCB size.

Recom Power Gmbh, RBBA3000
Looking for a buck-boost converter with high efficiency? Recom Power Gmbh offers a 3-kW buck-boost DC/DC converter with 98% efficiency in a half-brick baseplate-cooled package.

The RBBA3000 buck-boost, non-isolated DC/DC converter provides full power over an operating temperature of –40°C to 85°C when appropriately cooled.

Key features include an input range of 9 to 60 VDC, and the output voltage and maximum current can be user-programmed from 0 to 60 VDC and 0 to 50 A, respectively. Programming can be via a single resistor or by an externally applied voltage. The buck-boost topology allows the output voltage to be set lower or higher than the input voltage.

The load current can be monitored from a current-share pin, which can also be used to parallel two modules to provide up to a 100-A output with active load balancing.

The converter complies with EMC standard EN 55024 and also EN 55032 Class A and B with an external filter. Typical applications include 48-V to 24-V or 12-V to 24-V battery power conversion, electric vehicle voltage regulators, battery voltage stabilizers, and high-power laboratory DC power supplies.

CUI, VXO78-500-M
In the area of high efficiency, CUI Inc. recently introduced its first four-contact, surface-mount, non-isolated DC/DC converter, targeting information technology equipment, controls, and wide-input electronics applications. The ultra-compact VXO78-500-M offers a remote on/off pin and high efficiency up to 95%, making the power device suited for space-constrained applications that require maximized energy efficiency.

Key specs include 500-mA output current, no-load input current as low as 0.2 mA, a 4.75- to 36-VDC input voltage range, and a wide –40°C to 85°C temperature range. The devices are UL/EN/IEC 62368-certified.

Flex Power Modules, PUC-2B series
For designers who face both space and harsh environment challenges, Flex Power Modules has expanded its line of miniature DC/DC converters for industrial applications. The PUC-2B series, housed in a compact SIP7 package measuring 19.7 × 7.1 × 11.5 mm, are available in single- or dual-output options and deliver an output power of up to 2 W with no minimum load required.

The isolated, unregulated DC/DC converter modules offer a high efficiency, typically up to 85% with a 12-V output under full-load conditions. Other features include short-circuit protection and reinforced insulation.

The converters can operate over a temperature range from –40°C to 95°C and are suited for harsh industrial environments. The devices offer a mean time between failure (MTBF) rate of 12.9 million hours. They are safety-compliant to EN/UL 62368-1.

Polytron Devices, MTWA2 and MTWA4
DC/DC converters for medical products also need to meet high safety standards. Polytron Devices offers a family of 2- and 3.5-W DC/DC converters for medical applications that feature a low leakage current of 2 µA, a 5,000-VAC input to output isolation, and 2× MOPP patient protection, which is the highest level according to IEC 60601-1 safety standards for electrical medical products.

The 2:1 input range MTWA2 and MTWA4 DC/DC converters offer an extra-wide input range of 4.5-V to 12-VDC as well as 9-V to 18-VDC, 18-V to 36-VDC, and 36-V to 75-VDC input ranges. They also offer up to 82% efficiency, remote on/off, and a high operating altitude of 5,000 meters. Protection features include overvoltage, short-circuit, and undervoltage with no minimum load requirement.

Thanks to their low leakage current, availability in miniature DIP16 (0.95 × 0.57 × 0.41 in.) and SMD16 (0.95 × 0.57 × 0.40 in.) packages, and process efficiencies that deliver a lower cost, the MTWA2 and MTWA4 can be used in portable devices with low wattage requirements, the company said. The devices are also available in 4:1 input versions — the MTWB2 (2 W) and MTWB4 (3.5 W).