What components do I need to get started?
To make a functioning model of a device you need to have at least :
- A microcontroller (MCU) to execute instructions/operations. The microcontroller is like the brain of your device. You will describe in the Behavior of Wisebatt how the microcontroller will operate and drive the slave components in your device in order to achieve specific goals (e.g. gather data, analyze data, send the data...)
- A power source. This power source can be a battery alone or a battery and a regulator.
Additional key components are :
- A sensor. To measure data from its surroundings.
- A communication component. To communicate data towards the outside world.
A great way to design a device on Wisebatt is to
- start by choosing an MCU based on your requirement.
- select other components (e.g. communication, sensors, actuators, etc).
- select the battery and actuator that fits the best your voltage requirements.
How to select the best MCU for your device.
There are 3 axis on which you can base your choice :
- Number of peripherals.
- Processing speed.
- Price. It directly depends on the number of peripherals and the processing speed.
It is not possible to integrate ASICs (application-specific integrated circuit) directly in the library at the moment. Contact us on firstname.lastname@example.org if that’s an option that would interest you.
How to select the right components for your device.
When you design a device, you need to make sure that the supply voltage of all the components and the power sources are within the same range.
When adding a new component to your design space, here is a rule of thumb:
- The Vmax of the component you’re adding needs to be lower or equal to the lowest Vmax of the components already in your design. In addition, the Vmax of the component you’re adding needs to be higher or equal to the output voltage of its power source (i.e. battery or regulator): V_component_min < V_src < V_component_max.
- The Vmin of the component you’re adding needs to be higher or equal to highest Vmin of the components already in your design. In addition, the Vmin of the component you’re adding needs to be lower or equal to the output voltage of its power source (i.e. battery or regulator):V_component_min < V_src < V_component_max.
If you don’t follow this rule of thumb, the simulation will not work and your device might burn or simply not work.
How to select the best battery for your device.
Type of battery :
- Primary. Non-rechargeable battery. It is designed to be used once and discarded, and cannot be recharged with electricity and or reused like a secondary battery can be.
- Secondary. Rechargeable battery. It is a type of electrico-chemical battery which can be charged, discharged into a load, and recharged many times. Its energy density is usually lower than the primary batteries.
Max and Min Voltage of the battery :
The voltage behavior of a battery usually depends on its chemistry (e.g. Lead-acid, Lithium-Ion…).
Always make sure that the supply voltage of your components and batteries are within the same range.
Other requirements :
- Available Size. How big if your device? How much space do you have for the battery?
- Weight. The battery makes for a lot of the weight of a device. How heavy should it be?
- Water Resistance. Will your device be put under water or in a wet environment? Should it be sealed?
- Medical. Does your device need a medical certification?
- Certification. Several certification are needed when adding a battery to your device. Please check which certification you need to provide and keep in mind that an uncertified battery may require you to pass an additional certification.
Be careful when selecting your batteries : you should not have several different batteries in your device.
How to select the right regulator?
Type of regulator:
- Buck/LDO. Buck regulators are capable of decreasing a supply voltage. It means that the input supply voltage coming from the battery will always have to be greater than the output voltage of the regulator in order to keep on providing steady supply voltage to the regulator.
- Boost. Boost regulators are capable of increasing a supply voltage. It means that the input supply voltage coming from the battery will always have to be lower than the output voltage of the regulator in order to keep on providing steady supply voltage to the regulator.
- Buck-Boost. These regulators are capable of both decreasing and increasing a supply voltage.
Max and Min input Voltage of the regulators:
The input voltage range of a regulator usually depends on its architecture. Always make sure that the supply voltage of your regulators and batteries are within the same range depending on the regulator architecture.
Output supply Voltage of the regulators:
The supply voltage of the regulators will be used to supply your components. Make sure that it is in their supply voltage range : V_component_min < V_reg_out < V_component_max (i.e. the supply voltage is greater or equal to the lowest minimum supply voltage and lower to the maximum supported supply voltage)
Other requirements :
- Maximum current draw. How much current can your regulator supply to power your components?
- Quiescent current. How much current does your regulator consume?
- Control pin. Can your regulator be controlled by your MCU?
- Switching frequency. What is the switching frequency of your regulator (in case of switching regulators)? It can be especially important to consider this parameter when a radio is used as the regulator can generate noise.