A datasheet is a document in which a manufacturer describes the characteristics of a product, like an electronic component or module. It is primary meant for engineers, that is why it might be difficult to read for newbies. To use an electronic component you mostly don’t need to read and understand the complete datasheet. It also gives basic usage information, like pin descriptions, supply voltage, maximum allowable voltages and currents.

Datasheet Structure

  • After the introduction on the front page, detailed tables of electrical specifications follow. These will also list the absolute maximum ratings; maximal allowable values which a part can withstand before being damaged. If you go beyond these parameters, the part might get damaged, get hot, and even the ‘magic smoke’ might come out of the package.
  • Recommended operating conditions & Electrical Characteristics: This handles about the normal (preferred) usage. Use this information to design your circuit. Maybe you want to use your device (e.g. transistor, OpAmp) with a power supply of 3.3 Volt, because that is already available at your micro-controller board. This section of the datasheet tells you if that is possible. E.g. whether 3.3V is in the range of allowable supply voltages.
  • Some specs are depending on other parameters e.g. they are different for different supply voltages. Often these specs are put in a graph, but partially also in tables.
  • One of the most valuable topics in a datasheet is the application examples, showing real life applications. This is mostly direct applicable in your own circuit. Sometimes manufacturers also issue so-called ‘Application notes’. These are separate documents showing and discussing all kind of applications.

Component specific parameters

  • Some specifications are only typical for certain devices: OpAmps for example might have a spec. called Rail to Rail; naming refers to the power rail. Can the inputs and/or outputs handle voltages close to the power supply voltage.
  • Drop-out voltage is the voltage drop between input and output from a voltage regulator. Sometimes this needs to have a minimal value for the device to work. In other words; to work properly the input voltage of a voltage regulator must be high enough to give the specified output voltage. The sum of drop-out voltage and output voltage results in the  minimal input voltage.
  • Transistor datasheets show hfe, not found in any other datasheet. It is in fact the gain, which can be found in many different datasheets.

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