Ted,
I was hunting birdies, not looking for ways to reduce power.?
I was just sharing the power outcomes from what I did during a bird hunt, and also called my voltage dropping on the Nano a kludge. That was not my recommendation as the path forward to reduce power.
?
Agree that a switcher would be more power efficient. ?We already have three oscillators and now add a fourth?? Even as such, the LED backlight will consume more power when still biased at 5V (and to a lesser degree the ILI9341). That's what I meant by unnecessary.? I was not clear.? Better stated as?
It's very wasteful to bias the backlight at 5V, when it is designed to work at 3V.? If going down the added efficiency of a switcher, you'd also not use the 3.3V regulator on the display board and supply your own 3.3V.?
?
The challenge/issue with the Raduino's Nano is code space to add microcontroller control of display backlight.? ?The backlight On/Off as well as display brightness can be controlled via SPI.? Educated guess that brightness is done with PWM.? This would save power (especially with 5V applied) but a high potential to add more noise,? the opposite path I was going down at the time.
?
When you looked at the Raduino-TFT schematic, you should have seen the backlight control hard wired.? I stated "switch between R1 and +5V on the Raduino-TFT to turn off the backlight"? and provided a link to the website for the display information so you can see the backlight control.?
?
Regards,
Gary
