Voltage converter
What is a voltage converter?
As soon as the battery voltage of your machine is not 12V or 24V, it is certain that you will need a voltage converter. DC/DC converters are essential to the electrification of mobile machines and, more generally, to electro-mechanical power systems. They are used for a number of purposes:
Powering auxiliary equipment: High-voltage batteries (48V to over 400V) in electric vehicles need to be converted to 12V or 24V to power equipment such as lighting, screens, sensors and on-board computers.
Recharging the 12V lead-acid battery: Even in a 100% electric vehicle, a conventional lead-acid battery is often used to power on-board systems when the vehicle is stationary or in emergency mode. The DC-DC converter ensures constant recharging from the high-voltage battery.
Compatibility with multi-voltage architectures: Some vehicles combine several voltage levels (e.g. 48V for energy recovery systems and 12V for accessories). DC-DC converters provide smooth, efficient management of these different voltages.
How do I select a DC-DC converter?
1 // Input voltage
The input voltage corresponds to the DC voltage range that the converter can accept from the power source (battery, DC bus, etc.). It is essential to choose a model adapted to the actual voltage of the system, taking possible variations into account (for example: 60 to 160V for a nominal 120V battery).
2 // Output voltage
The output voltage is the DC value delivered by the converter to power the equipment. The most common voltages are 12V or 24V, but other values are possible depending on requirements. Regulation of this voltage must be precise, even if the input voltage fluctuates.
3 // Output power
The maximum power that the converter can supply (expressed in watts) must be sufficient to cover the cumulative requirements of the connected equipment. A margin is recommended to avoid overloading and ensure long-term reliability.
4 // Enable command (‘Enable’ input)
Some converters incorporate an ‘Enable’ input that enables the output to be activated or deactivated via a control signal. This makes it possible to cut the power supply to certain circuits when not required, thus optimising the system’s energy consumption.
5 // Type of connector
The type of connector has an impact on the integration of the product: some models have cables moulded directly into the casing for enhanced watertightness, while others are fitted with connectors for easier maintenance or replacement. The choice depends on the system’s environmental and maintenance constraints.
6 // Galvanic isolation input/output
Some DC-DC converters offer galvanic isolation between input and output. This means that there is no direct electrical connection between the two circuits: energy is transferred via a transformer or other isolation technology.
This isolation protects sensitive equipment, limits ground loops and improves safety, particularly in systems where the input and output operate at very different potentials. This is an important criterion in demanding environments or those subject to electromagnetic interference.
