To deliver efficiency gains, today’s electronic systems are increasingly modular. In particular, those that are battery-powered have various voltage requirements. While core digital control and data processing sub-systems typically use a supply voltage of 1.8 V (or lower such as 1.2 V / 0.8 V), analog and mixed-signal peripherals still operate at 3.3 V or even 5 V. That’s why voltage translation has become an important part of electronic design, ensuring devices work together without signal loss or damage.
With over 750 products answering this need, Nexperia clearly has a solution to fit your design. So, which level-translation technique is best for your system? Let’s look at some of the key types of voltage translation to help you find the most suitable solution to your technical challenge.
Is it just one way or bi-directional?
Uni-directional translation is the most common type and consists of either Low-to-High or High-to-Low translation with data transmission. There are also situations where bi-directional translation is required, with both data transmission and reception. Within these two categories, various translation techniques can solve your challenge, each with its own advantages and limitations.
Clamp diodes with current-limiting resistors are a basic approach to translate any voltage to a lower level. However, these do require external components to be implemented. If you are looking for a simpler solution, ESD devices with overvoltage-tolerant inputs can be considered. Using CMOS technology, these devices can offer similar performance and lower system power than clamp diodes, however the input cannot be driven at voltages greater than the recommended maximum VCC.
If you need Low-to-High voltage translation, you will have to consider two other solutions. Devices with open-drain outputs which can be pulled-up to the desired voltage level are ideal for Low-to-High scenarios, although these will require additional system power and a pull-up resistor to be added to the circuitry. Alternatively, CMOS devices with low-threshold inputs can be employed without external components and keeping the same footprint as a standard function. Nevertheless, default conditions are more constraining and higher power dissipation could be expected.
Multiple domains or bi-directional translation
If you have more than two voltage domains to interface, then make sure to look for open-drain outputs. Whether these are combined with overvoltage-tolerant inputs, clamp diode inputs or low-threshold inputs, you will be able to create a modular design interconnecting with three voltage domains.
Alternatively, for flexibility in translating to and/or from a variety of voltage nodes, our dedicated dual-supply devices have two supply voltages at different voltage ranges covering 0.8 V to 3.6 V and 1.2 V to 5.5 V. Nexperia also markets products for specific voltage translations needs, such as our Bus Switches for 5 V to 3.3 V systems or 3.3 V to 1.8 V systems.
For more information about our voltage translation portfolio including examples and circuit diagrams, download our Logic Translators Guide and contact your Nexperia representative or distributor.
Michael Lyons is the Senior Product Manager for Logic at Nexperia. He has over 25 years of experience in semiconductor product development and engineering. Michael has held various marketing, business and product management roles during his career.