Specifications

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Figure 2.2.6-1: Configuration of the LM1117V33 as a fixed-output voltage
regulator. Copyright STMicroelectronics. Used with permission.
As mentioned previously, size is a concern for this project. The compact size of
this unit is a very attractive quality, as it allows for much more efficient use of the
available space on both PCBs. In addition, the low cost allows for multiple
application points on the board in order to design a higher quality power supply.
2.3.7 TL780-05 5Vdc Voltage Regulator
This regulator IC is similar to the LM1117V33, except that it offers a fixed output
of 5Vdc. It also offers the desired elements of basic power protection, including
short circuit protection across the output terminals. Depending on the final
implementation of the project, it may be desirable to utilize the TL780-05 in
addition to the LM1117V33, in order to provide regulated 5Vdc and 3.3Vdc.
Although many circuit ICs may be able handle up to 5V, it may not be desirable
to be running components at their upper tolerance, especially as a major
consideration of this project is its long term reliability and accuracy. As such, it
may still be necessary to use the 3.3Vdc regulator in addition to this 5Vdc
regulator.
Size, temperature, and input data are similar to the LM1117V33. As such, they
will not be repeated. One possible implementation is straightforward, as shown in
Figure 2.2.7-1. Other configurations can allow the output voltage to be adjusted
away from its fixed 5V; however that should not be necessary for this project.