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The Remote On/Off or Control pin is commonly used for the following reasons:
To control a high-power converter using a low-power signal. The input power of a control pin is typically only a few milliwatts, but it can enable or disable a converter of as much as a hundred watts. This means that the low power output of a microcontroller or logic IC can be used to control a system without the need of extra amplifiers or bulky relays.
To power-up or power-down a system of several converters in the right sequence. Many complex power supplies need to start up or shut down in a certain order to be safe. An example could be a computer-based controller where the microprocessor should be up and running before the peripherals are powered up. Another example is where one power supply feeds another. The primary power supply often should have reached a stable output voltage before the secondary power supplies are turned on.
To save energy. A control pin can be used to turn off the power completely to parts of a circuit during standby mode, while leaving a central watchdog circuit still active. This is especially important for battery powered circuits because all DC/DC converters draw some power even when they are not loaded.
To reduce the inrush current. In a system of several parallel sub-systems, it is often useful to stagger the start-up of each sub-system so as not to overload the primary power supply or cause the main fuse to trip or blow on switch-on.

The converters are not vacuum potted because we use a special process to remove the air bubbles (voids). The epoxy potting process is as follows:
1- The two-component epoxy is mixed and placed under a vacuum for 1 minute to remove any air bubbles created by the mixing process.
2- The plastic case is 1/3 filled and allowed to rest.
3- The pre-tested converter pcb is inserted into the case and 2/3 filled and allowed to rest.
4- The part completed converters are placed in a warm oven (30°C) for 20 minutes to allow any air bubbles to rise to the top.
5- The case is sealed with a harder grade of epoxy and baked at 50°C for one hour to cure.
6- In addition, spot checks are made with our X-ray machine to monitor and ensure that air voids are not present in any of our converters.
The silicone rubber potting process is as follows:
1- The pre-mixed silicone rubber compound is injected into the case
2- The case is placed on to a shaker and vibrated to encourage any air bubbles to rise to the surface
3- The case is topped up to the fill level
4- The converters are put aside to cure at room temperature.

An unregulated converter is a cheaper solution but offers less output voltage stability. The output voltage can change depending on both the load and the input voltage variations. Therefore, the input voltage range is restricted to +/-5% or +/-10% , so it is recommended to use unregulated DC/DC cpnverters only with a regulated supply voltage. The output voltage can rise substantially during no-load conditions, but, even an unregulated converter offers a low output voltage variation over a 20% to 100% load range.

Regulated converters offer a much better load and line voltage regulation, typically less than 1%, so the output voltage is not dependant on the load or input voltage. In particular, the output voltage remains stable under low load or no load conditions. In addition, the input voltage range is higher (2:1, 4:1 or up to 7:1 with non-isolated converters), so regulated converters are suitable for use with variable input voltage supplies such a batteries or multiple supply voltages (e.g, 12V or 24V supplies)

The RCD-24 series is step-down (buck) converter. You always need a higher input voltage than the output voltage required. A high power LED usually has a forward voltage drop of around 3.4V, so only three LEDs can be drivenin series from a 12V source. If the input voltage is increased to 24V, seven LEDs can be in the chain and if the input voltage is 36V, then ten LEDs can be driven.
However, it is possible to connect chains of LEDs in parallel, so a RCD-24-7.0 can drive two chains of three 350mA LEDs connected in parallel.
Remember that this part is a constant current converter, so the output voltage is variable depending on the power needed, but it will always be lower than the input voltage.

All of our DC/DC converters contain a built-in input capacitor filter, so an external capacitor is not required for normal operation, unless specified in the datasheet. An input capacitor may also be required to meet surge requirements or to smooth the DC supply at the point of load. If several DC/DCs are powered from the same rail, then input capacitors placed close to the input pins are recommended.

The main safety standard, originally intended for office equipment, that has been used for power converters in general. The international version (IEC 60950-1) and the US/Canada versions (UL 60950-1, CSA C22.2 No. 60950) remain valid for legacy products, but the European version (EN 60950-1) has a date-of-withdrawal of the end of 2020, after which it can no longer be used for presumption of CE conformity and other standards must be applied such as EN 62368-1.

The main safety standard for measurement, control and laboratory equipment. UL, CSA, IEC and EN versions of this standard exist.

The safety standard for the particular requirements of control equipment. UL 61010-2-201 replaces the popular UL 508 standard.

A capacitor is a passive electronic component that consists of two conductive plates or foils separated by an insulating dielectric. A voltage applied to the plates develops an electric field across the dielectric and causes the plates to accumulate a charge. When the voltage source is removed, the field and the charge remain until discharged, storing energy. Capacitance is measured in farads, but typical values are microfarads (µF), or nanofarads (nF).

Railway applications - Insulation coordination - Part 1: Basic requirements - Clearances and creepage distances for all electrical and electronic equipment; EU version EN 50124-1:2017

End of Life: After a product has reached End of Life status, it will be removed from the standard product range and is no longer for sale. The datasheet is still available on the RECOM website. In a period before this, the product will be designated as ‘No longer Recommended for New Designs (NRND)’.

A circuit that shapes the frequency-dependent gain and phase response of a feedback loop so that it remains stable under all operating conditions.

Highway Addressable Remote Transducer communication is a commonly used mode of transmission for digital signals that are superimposed on the analog signal of a 4–20mA current loop. This allows both instantaneous analog readings with supplementary digital data on the same wiring system.

A power supply arrangement consisting of two or more units wired in parallel, any one of which can be removed and replaced while the system remains powered up, without interruption to the output supply to the load.

Infrared: Light that has a frequency just below the visible light spectrum, used for remote controls and night vision applications, for example.

Nanoampere(s): Unit of current measurement. A billionth of an amp.

In A/D conversion, the Nyquist principle (derived from the Nyquist-Shannon sampling theorem) states that the sampling rate must be at least twice the maximum bandwidth of the analog signal in order to allow the signal to be reproduced. The maximum bandwidth of the signal (half the sampling rate) is commonly called the Nyquist frequency.

Refer also to Ishare. Some power converters can be connected in parallel to increase the current available for a load, typically with an active or passive load share function. Parallel operation can also be used for redundancy where one or more ‘redundant’ power converters can be removed from the system leaving sufficient power available for the load.

Power-over-Ethernet: A means for delivering power to a remote device using the same cable lines used to deliver Ethernet data. Can be used to power remote devices (cameras, LED-lighting, door entry systems) over a single combined power and bi-directional data cable. The nominal PoE voltage supply is 44-57VDC, so a DC/DC converter is typically required at the end device. This DC/DC must negotiate with the primary power supply to release enough current for its needs (available power is restricted between 4W and 100W depending on a complex sequence of signature resistances offered by the DC/DC negotiation IC). The relevant standard defining this interface is IEEE 802.3af /at/bt. Many think that PoE is the future for indoor LED lighting.

Positive Temperature Coefficient (thermistor): When the resistance of a component rises with temperature, it is said to have a positive temperature coefficient. Example: Hewlett-Packard's first commercial product, an audio oscillator, used a common light bulb as a PTC element in the feedback circuit to maintain constant output amplitude regardless of frequency. PTC Thermistors can be used in power supplies for overtemperature protection and temperature measurement.

Used to compensate for voltage drops in connections to a power converter load. Implemented with positive and negative ‘sense’ wires which connect to the point where most accurate regulation is required.

Radio Frequency IDentification: A method for remotely identifying an object using a tag or module that carries a unique ID code, which can be activated by an external RF field which powers the tag, enabling transmission of the code back to a ‘reader’.

A resistor placed in a current path to allow the current to be measured. The voltage across the sense resistor is proportional to the current that is being measured. Typical value is in milliohms. A Kelvin shunt has separate current and voltage connections to increase the measurement accuracy.

A sensor that processes the raw measurement data and only sends relevant updates to reduce the amount of data traffic. Important for the concept of IoT if billions of devices are to be networked.

An ISO Technical Specification that aligns various automotive quality systems standards within the global automotive industry. Together with ISO 9001:2000, ISO/TS 16949:2002 specifies the quality system requirements for the design/development, production, installation and servicing of automotive related products. RECOM’s factories in Taiwan are ISO/TS 16949 certified.