Common in many commercial products is the the use of "local" regulators. This typically means that a peripheral/Device that is external to the microcontroller has its own supply source/Regulator. This helps prevent these devices from adversely affecting power rail and can also allows the microcontroller to control when these devices power up.
An example application might be using an LCD/OLED module with in a project.
Some LCD/OLED modules generate substantial noise that can be seen on the power rail. This can cause problems with other devices. Having a separate regulator for the LCD/OLED module can reduce or eliminate this.
Another example might be when using an RF Module where a very clean supply is necessary for optimal receive sensitivity (Range).
For many projects I use an LD2951 (100ma) Regulator as a local regulator for devices. If more current is needed I like to use a TPS72xxQP (250ma) or TPS73xxQP (500ma). There are other choices. I just used these as examples.
In a recent project I used an LD2951 (5V) as a local regulator for a cheap ASK RF module. Doing so allowed the microcontroller to turn the module ON/OFF when needed and range was nearly doubled as a result of local/low noise regulation.
The temptation/fad these days is to design for "minimal component count .., where a few cents and a few few mm2 of board space can be saved. However, in a poorly enginered design these perceived savings can cost dearly in the form of poor and erratic performance.
William
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Using Local Regulators
Common in many commercial products is the the use of "local" regulators. This typically means that a peripheral/Device that is external to the microcontroller has its own supply source/Regulator. This helps prevent these devices from adversely affecting power rail and can also allows the microcontroller to control when these devices power up.
An example application might be using an LCD/OLED module with in a project.
Some LCD/OLED modules generate substantial noise that can be seen on the power rail. This can cause problems with other devices. Having a separate regulator for the LCD/OLED module can reduce or eliminate this.
Another example might be when using an RF Module where a very clean supply is necessary for optimal receive sensitivity (Range).
For many projects I use an LD2951 (100ma) Regulator as a local regulator for devices. If more current is needed I like to use a TPS72xxQP (250ma) or TPS73xxQP (500ma). There are other choices. I just used these as examples.
In a recent project I used an LD2951 (5V) as a local regulator for a cheap ASK RF module. Doing so allowed the microcontroller to turn the module ON/OFF when needed and range was nearly doubled as a result of local/low noise regulation.
The temptation/fad these days is to design for "minimal component count .., where a few cents and a few few mm2 of board space can be saved. However, in a poorly enginered design these perceived savings can cost dearly in the form of poor and erratic performance.
William