DESIGN CONSIDERATIONS

Input Source Impedance

The impedance of the input source connecting to the DC/DC power modules will interact with the modules and affect the stability. A low ac-impedance input source is recommended. If the source inductance is more than a few µH, we advise adding a 10 to 100 µF electrolytic capacitor (ESR < 0.7 Ω at 100 kHz) mounted close to the input of the module to improve the stability.

Layout and EMC Considerations

Delta’s DC/DC power modules are designed to operate in a wide variety of systems and applications. For design assistance with EMC compliance and related PWB layout issues, please contact Delta’s technical support team. An external input filter module is available for easier EMC compliance design. Application notes to assist designers in addressing these issues are pending release.

Safety Considerations

The power module must be installed in compliance with the spacing and separation requirements of the end- user’s safety agency standard, i.e., UL60950, CAN/CSA-C22.2 No. 60950-00 and EN60950:2000 and IEC60950-1999, if the system in which the power module is to be used must meet safety agency requirements.

When the input source is 60 Vdc or below, the power module meets SELV (safety extra-low voltage) requirements. If the input source is a hazardous voltage which is greater than 60 Vdc and less than or equal to 75 Vdc, for the module’s output to meet SELV requirements, all of the following must be met:

The input source must be insulated from any hazardous voltages, including the ac mains, with reinforced insulation.

One Vi pin and one Vo pin are grounded, or all the input and output pins are kept floating.

The input terminals of the module are not operator accessible.

If the metal baseplate is grounded the output must be also grounded.

A SELV reliability test is conducted on the system where the module is used to ensure that under a single fault, hazardous voltage does not appear at the module’s output.

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Do not ground one of the input pins without grounding one of the output pins. This connection may allow a non-SELV voltage to appear between the output pin and ground.

The power module has extra-low voltage (ELV) outputs when all inputs are ELV.

This power module is not internally fused. To achieve optimum safety and system protection, an input line fuse is highly recommended. The safety agencies require a normal-blow fuse with 7A maximum rating to be installed in the ungrounded lead. A lower rated fuse can be used based on the maximum inrush transient energy and maximum input current.

Soldering and Cleaning Considerations

Post solder cleaning is usually the final board assembly process before the board or system undergoes electrical testing. Inadequate cleaning and/or drying may lower the reliability of a power module and severely affect the finished circuit board assembly test. Adequate cleaning and/or drying is especially important for un-encapsulated and/or open frame type power modules. For assistance on appropriate soldering and cleaning procedures, please contact Delta’s technical support team.

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Delta Electronics Series Q48DR manual Design Considerations, Input Source Impedance

Series Q48DR specifications

Delta Electronics, a prominent player in power management solutions, has expanded its product portfolio with the introduction of the Series Q48DR. This versatile DC-DC converter is specifically designed to meet the rigorous demands of modern industrial, telecommunications, and networking applications. The Q48DR series is noted for its high efficiency, compact design, and wide input voltage range, making it an ideal choice for power-sensitive environments.

One of the standout features of the Q48DR series is its high efficiency rating, typically exceeding 90%. This efficiency translates into reduced energy consumption and lower thermal output, which is crucial in applications requiring continuous operation. The advanced topology employed in the Q48DR not only maximizes energy conversion but also ensures minimal power losses across a variety of loads.

The input voltage range of the Q48DR is impressively broad, accommodating inputs from 36V to 75V DC. This wide input range ensures compatibility with a variety of power systems, simplifying integration in different setups. Moreover, the output voltage is adjustable, allowing users to fine-tune the power supply to match specific application requirements, typically ranging from 12V to 3.3V.

In addition to flexibility, the Q48DR series incorporates an array of protective features. These include overload protection, over-voltage protection, and thermal shutdown. These safety mechanisms are essential for safeguarding sensitive electronic components and maintaining system reliability in demanding environments.

The construction of the Q48DR is another important aspect, with a compact design that facilitates easier installation in space-constrained applications. The converter is housed in a robust metal casing, providing EMI shielding and thermal management. This design ensures that the unit can operate reliably in harsh industrial settings while minimizing electromagnetic interference with other devices.

Furthermore, Delta Electronics places a strong emphasis on sustainability. The Q48DR series meets RoHS standards, reflecting the company's commitment to reducing environmental impact without compromising performance. With a comprehensive range of certifications, including UL and CE, the Q48DR is built to provide peace of mind to users while ensuring compliance with global standards.

In summary, the Delta Electronics Series Q48DR DC-DC converter exemplifies advanced power management through its high efficiency, versatile input/output specifications, protective features, and compact design. These characteristics make it an ideal solution for a multitude of applications in various sectors, ensuring reliable performance and ease of integration.