Power Cheater

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Introduction

The Power Cheater Board provides a simple Level Shifter between a standard USB-Serial Converter from 5V to 3.3V and also serves as a 3.3V linear power supply to the project board. It works nicely with the Cheater Board. Power can be applied to the board from the USB-Serial Converter, Externally through the terminal block, or through a JST connector via a typical Lithium battery.

PowerCheaterGerber.png

The inspiration to make this board came from the need for a cheap power supply for the ESP8266 WiFi Module with low quiescent current draw. This video here describes the power supply and benchmarks the regulators that are compatible with this board:

The MOSFET Level Shifters are Explained in this video:

Here's the schematic for reference:

PowerCheaterSCH.png

Assembly

The board ships as a bare board like this:

PowerCheaterBareBoard.png

The board can be assembled easily, since it only consists of through hole components, then it looks like this, then when plugged into the Cheater board using the USB-Serial Converter:

PowerCheaterAssy.png

PowerCheaterConnected.png

Parts

It is up to you to order the parts. The list can be downloaded **HERE**. This can be directly uploaded into Digikey if you'd like. The parts are pretty self explanatory - make sure that you pay attention to which way the Radio Modules plug into the board. There are markings/text on the board indicating which header each module should be used for.

Pin Out

ESP8266:

  • TX from the ESP8266 goes to Arduino Pin 6 - pin 6 would be a Software Serial RX
  • RX to the ESP8266 comes from Arduino Pin 7 - pin 7 would be a Software Serial TX
  • GPIO 2 is not connected
  • GPIO 0 is connected to one of the pushbuttons (under the ESP8266) pulled LOW when pressed - floating when not pressed
  • RESET is connected to the other pushbutton (under the NRF24L01+) pulled LOW when pressed

NRF24L01+:

  • IRQ is connected to Arduino Pin 2 - Interrupt 0
  • CE is connected to Arduino Pin 4
  • CSN is connected to Arduino Pin 5
  • CLOCK is connected to Arduino Pin 13
  • MOSI is connected to Arduino Pin 11
  • MISO is connected to Arduino Pin 12
  • Note that Arduino Pin 10 will not be useable, since the NRF24L01+ communicates via SPI, thus making the SS (Slave Select) pin not useable - there may be workarounds for this.

Test Code

Coming soon!