Published August 11, 2022 © GPL3+

3S Battery Charger

Build your own Li-Po & Li-ion Balance Charger for under $10

IntermediateFull instructions provided8 hours2,911

Things used in this project

Hardware components

Microchip ATtiny1614 Microprocessor

ElectroPeak 0.96" OLED 64x128 Display Module

Passive Components

3 x 3000 ohm 1% 0805 resistors, 3 x 1000 ohm 1% 0805 resistors, 3 x 0.1uF 0805 capacitors

HX-3S-HJ20 3S Battery Balancing Module

1117-50 Regulator

5V SOT223 regulator

4 Pin JST 2.54mm socket

DC Panel socket

Software apps and online services

Arduino IDE

Hand tools and fabrication machines

3D Printer (generic)

Soldering iron (generic)

Story

Recently I purchased some 3S Li-Po batteries for a project I was working on. Unlike single cell batteries, batteries with multiple cells should be charged in a balanced way. This is to ensure that any single cell is not overcharged and hence possibly damaged.

500mAH 3S battery that I recently purchased

Note that the battery has a two connecters. The 2 pin connecter is the output of all three internal Li-Po cells in series. The 4 pin connector is the charging plug and corresponds to the B-, B1, B2 and B+ connections as shown in the diagram below.

So rather than pay $30+ for a commercial battery charger, I decided to make my own using a 3S battery balancing board from AliExpress (Cost around $3).

3S Battery Balancing Module found on sites like eBay, AliExpress, Banggood, etc

One option is to connect the battery as shown above and feed 12.6V to P+ and P-. You should use a constant current source to limit the current to the mAH rating of the battery. The cells are fully charged when each cell is charged to 4.2V. You can check this with a volt meter.

To simply this process, my build displays the voltages across each of the cells on a OLED display. You can easily see when the battery is fully charged or if you have a faulty cell that fails to charge.

Schematic

The circuit is built around a ATtiny1614 microprocessor driving a I2C OLED display and monitoring the voltage at each connection of the Battery Balancing Module (HX-3S-JH20). Each voltage is passed through a voltage divider so it doesn't overload the analog pin on the microprocessor.

Schematic of the Battery Charger

Board

The Eagle files have been included should you wish to have the board commercially made or you can do as I did and make it yourself. I used the Toner method.

PCB layout

Start by adding the SMD components. I find it easier to use solder paste rather than use solder from a reel when soldering SMD components.

Add the links if your PCB is single-sided.

Add the power and UPDI 4 pin header to the copper side of the board.

Add the 4 pin JST socket and HX-3S-JH20 module to the component side.

3D print Spacer.stl. This is glued to the copper side after fitting the OLED screen. I used a 4 pin female Dupont header with long pins to plug the OLED module into. Once positioned, solder the female connector to the copper side of the board and glue the spacer to the PCB using super glue. The OLED module was held in place using 2 x 4mm M2 screws.

The Spacer.stl holds the OLED display and is glued to the copper side of the board

Screw the PCB into the case using 4 x 4mm M2 screws

Programming

Unlike the earlier ATtiny series such as the ATtiny85, the ATtiny1614 uses the RESET pin to program the CPU. To program it you need a UPDI programmer. I made one using a Arduino Nano. You can find complete build instructions at Create Your Own UPDI Programmer. It also contains the instructions for adding the megaTinyCore boards to your IDE.

My home-made UPDI programmer

Once the board has been installed in the IDE, select it from the Tools menu.

Select the Attiny1614 board in your IDE

Select the ATtiny1614 board in your IDE

Select Board, chip, clock speed, COM port the Arduino Nano is connected and the programmer

The Programmer needs to be set to jtag2updi (megaTinyCore).

Open the sketch and upload it to the ATtiny1614.

Using the unit

Li-Po batteries when flat, can draw a large amount of current when charging. You must limit this current otherwise the battery could overheat and catch on fire. I used my DC-580 DC Boost and Buck Adjustable Power Supply that I built a while back. Set the current to the mAH of the battery. My battery is 500mAH so it the charge current shouldn't exceed 500mA. The voltage should be 12.6V for a 3 cell battery (4.2V x 3). Exceeding this voltage is likely to damage the battery.

Plug in the 3S battery and apply 12.6V from a constant current power supply.

The OLED display will show the battery voltages and the voltage across each cell. The battery is fully charged when all cells are around 4.2V

Conclusion

It isn't really a self-contained unit because of the power source that is also required. It was a interesting build and it does the job that was intended so all in all, a useful build 👍.

Schematics

Code

/**************************************************************************
 ATtiny1614 3S Battery Charger

 2021-08-10 John Bradnam (jbrad2089@gmail.com)
   Create program for ATtiny1614

 --------------------------------------------------------------------------
 Arduino IDE:
 --------------------------------------------------------------------------
  BOARD: ATtiny1614/1604/814/804/414/404/214/204
  Chip: ATtiny1614
  Clock Speed: 20MHz
  millis()/micros(): "Enabled (default timer)"
  Programmer: jtag2updi (megaTinyCore)

  ATTiny1614 Pins mapped to Ardunio Pins
 
              +--------+
          VCC + 1   14 + GND
  (SS)  0 PA4 + 2   13 + PA3 10 (SCK)
        1 PA5 + 3   12 + PA2 9  (MISO)
  (DAC) 2 PA6 + 4   11 + PA1 8  (MOSI)
        3 PA7 + 5   10 + PA0 11 (UPDI)
  (RXD) 4 PB3 + 6    9 + PB0 7  (SCL)
  (TXD) 5 PB2 + 7    8 + PB1 6  (SDA)
              +--------+
  
 **************************************************************************/

#include "Tiny8kOLED.h"   // This is the modified library (M.V. Predoi)
#include <Wire.h>

//Inputs
#define C3_PIN 10   //PA3
#define C2_PIN 1    //PA5
#define C1_PIN 2    //PA6

#define ADC_C3 ADC_MUXPOS_AIN3_gc
#define ADC_C2 ADC_MUXPOS_AIN5_gc
#define ADC_C1 ADC_MUXPOS_AIN6_gc

float supplyVoltage = 0;            //VDD from 5V regulator
float C3Voltage = 0;                //Last reading from C3 (12.6)
float C2Voltage = 0;                //Last reading from C2 (8.4)
float C1Voltage = 0;                //Last reading from C1 (4.7)

char sBuf[32];

//-------------------------------------------------------------------------
// Initialise Hardware
void setup(void)
{
  pinMode(C3_PIN, INPUT);
  pinMode(C2_PIN, INPUT);
  pinMode(C1_PIN, INPUT);

  //Setup ADC
  VREF.CTRLA = VREF_ADC0REFSEL_1V1_gc;
  ADC0.CTRLC = ADC_REFSEL_VDDREF_gc | ADC_PRESC_DIV256_gc; // 78kHz clock
  ADC0.CTRLA = ADC_ENABLE_bm;                              // Single, 10-bit

  measureSupplyVoltage();

  oled.begin();
  oled.clear();
  oled.setFont(FONT8X16);
  oled.setCursor(0,0);
  oled.print(F("C3:"));
  oled.setCursor(0,2);
  oled.print(F("C2:"));
  oled.setCursor(0,4);
  oled.print(F("C1:"));

}

//--------------------------------------------------------------------
// Main program loop
void loop(void)
{

  //Input voltages are feed through a voltage divider which
  //divides the input voltage by 4 so they need to be multiplied by 4. 
  C3Voltage = measureVoltage(ADC_C3) * 4;
  C2Voltage = measureVoltage(ADC_C2) * 4;
  C1Voltage = measureVoltage(ADC_C1) * 4;

  oled.setCursor(30,0);
  oled.print(String(C3Voltage,2)+"  ");
  oled.setCursor(80,0);
  oled.print(String(C3Voltage-C2Voltage,2)+" ");
  
  oled.setCursor(30,2);
  oled.print(String(C2Voltage,2)+"  ");
  oled.setCursor(80,2);
  oled.print(String(C2Voltage-C1Voltage,2)+" ");
  
  oled.setCursor(30,4);
  oled.print(String(C1Voltage,2)+"  ");
  oled.setCursor(80,4);
  oled.print(String(C1Voltage,2)+" ");

  delay(1000);
  
}

//--------------------------------------------------------------------------
// Measure supply voltage
// Source: David Johnson-Davies - www.technoblogy.com - 13th April 2021
void measureSupplyVoltage() 
{
  ADC0.MUXPOS = ADC_MUXPOS_INTREF_gc;                  // Measure INTREF
  ADC0.COMMAND = ADC_STCONV_bm;                        // Start conversion
  while (ADC0.COMMAND & ADC_STCONV_bm);                // Wait for completion
  uint16_t adc_reading = ADC0.RES;                     // ADC conversion result
  supplyVoltage = 1126.4 / adc_reading;
}

//--------------------------------------------------------------------------
// Measure voltage of a given pin
// adcMux - ADC_Ax constant for the pin to measure
float measureVoltage(uint8_t adcMux) 
{
  ADC0.MUXPOS = adcMux;                                // Measure Analog pin
  ADC0.COMMAND = ADC_STCONV_bm;                        // Start conversion
  while (ADC0.COMMAND & ADC_STCONV_bm);                // Wait for completion
  uint16_t adc_reading = ADC0.RES;                     // ADC conversion result
  return supplyVoltage * adc_reading / 1024;
}

/*
 * SSD1306xLED - Drivers for SSD1306 controlled dot matrix OLED/PLED 128x64 displays
 *
 * @created: 2014-08-12
 * @author: Neven Boyanov
 *
 * Source code available at: https://bitbucket.org/tinusaur/ssd1306xled
 * Modified by M.V. Predoi 2018-09-25
 */

#include <stdint.h>
#include <Arduino.h>
#include <Wire.h>  
#include <util/delay.h>

/* Uncomment from the 3 line below this note, the fonts you intend to use:
*  FONT6X8  = 764 bytes
*  FONT8X16 = 1776 bytes
*  FONT16X32= 1334 bytes
*/
 #define FONT6X8		0
 #define FONT8X16	1
 #define FONT16X32	2

// ----------------------------------------------------------------------------

#ifndef SSD1306
	#define SSD1306		0x3C	// Slave address
#endif

// ----------------------------------------------------------------------------

class SSD1306Device: public Print {

    public:
		SSD1306Device(void);
		void begin(void);
		void setFont(uint8_t font);
		void ssd1306_send_command(uint8_t command);
		void ssd1306_send_data_byte(uint8_t byte);
		void ssd1306_send_data_start(void);
		void ssd1306_send_data_stop(void);
		void setCursor(uint8_t x, uint8_t y);
		void fill(uint8_t fill);
		void clear(void);
		void bitmap(uint8_t x0, uint8_t y0, uint8_t x1, uint8_t y1, const uint8_t bitmap[]);
		void ssd1306_send_command_start(void);
		void ssd1306_send_command_stop(void);
		void ssd1306_char_f8x16(uint8_t x, uint8_t y, const char ch[]);
		virtual size_t write(byte c);
  		using Print::write;


};


extern SSD1306Device oled;

// ----------------------------------------------------------------------------

/*
 * SSD1306xLED - Drivers for SSD1306 controlled dot matrix OLED/PLED 128x64 displays
 *
 * @created: 2014-08-12
 * @author: Neven Boyanov
 *
 * Source code available at: https://bitbucket.org/tinusaur/ssd1306xled
 *
 */

// ----------------------------------------------------------------------------

#include <stdlib.h>
#include <avr/io.h>

#include <avr/pgmspace.h>

#include "Tiny8kOLED.h"

#ifdef FONT6X8			// In case font6x8 is defined: load it
	#include "font6x8.h"
#endif

#ifdef FONT8X16			     // In case font8x16 is defined: load it
	#include "font8x16.h"
#endif

#ifdef FONT16X32			     // In case font16x32 is defined: load it
	#include "font16x32.h"
#endif



// ----------------------------------------------------------------------------

const uint8_t ssd1306_init_sequence [] PROGMEM = {	// Initialization Sequence
	0xAE,			// Display OFF (sleep mode)
	0x20, 0b00,		// Set Memory Addressing Mode
					// 00=Horizontal Addressing Mode; 01=Vertical Addressing Mode;
					// 10=Page Addressing Mode (RESET); 11=Invalid
	0xB0,			// Set Page Start Address for Page Addressing Mode, 0-7
	0xC8,			// Set COM Output Scan Direction
	0x00,			// ---set low column address
	0x10,			// ---set high column address
	0x40,			// --set start line address
	0x81, 0x3F,		// Set contrast control register
	0xA1,			// Set Segment Re-map. A0=address mapped; A1=address 127 mapped. 
	0xA6,			// Set display mode. A6=Normal; A7=Inverse
	0xA8, 0x3F,		// Set multiplex ratio(1 to 64)
	0xA4,			// Output RAM to Display
					// 0xA4=Output follows RAM content; 0xA5,Output ignores RAM content
	0xD3, 0x00,		// Set display offset. 00 = no offset
	0xD5,			// --set display clock divide ratio/oscillator frequency
	0xF0,			// --set divide ratio
	0xD9, 0x22,		// Set pre-charge period
	0xDA, 0x12,		// Set com pins hardware configuration		
	0xDB,			// --set vcomh
	0x20,			// 0x20,0.77xVcc
	0x8D, 0x14,		// Set DC-DC enable
	0xAF			// Display ON in normal mode
	
};

uint8_t oledFont, ci, oledX, oledY;

// Program:    5248 bytes

SSD1306Device::SSD1306Device(void){}


void SSD1306Device::begin(void)
{
	Wire.begin();
	
	for (uint8_t i = 0; i < sizeof (ssd1306_init_sequence); i++) {
		ssd1306_send_command(pgm_read_byte(&ssd1306_init_sequence[i]));
	}
	clear();
}


void SSD1306Device::setFont(uint8_t font)
{
	oledFont = font;
}

void SSD1306Device::ssd1306_send_command_start(void) {
	Wire.beginTransmission(SSD1306);
	Wire.write(0x00);	// write command
}

void SSD1306Device::ssd1306_send_command_stop(void) {
	Wire.endTransmission();
}

void SSD1306Device::ssd1306_send_data_byte(uint8_t byte)
{
/*  
	//if(Wire.writeAvailable()){
		ssd1306_send_data_stop();
		ssd1306_send_data_start();
	//}
 */
	Wire.write(byte);
	
}

void SSD1306Device::ssd1306_send_command(uint8_t command)
{
	ssd1306_send_command_start();
	Wire.write(command);
	ssd1306_send_command_stop();
}

void SSD1306Device::ssd1306_send_data_start(void)
{
	Wire.beginTransmission(SSD1306);
	Wire.write(0x40);	//write data
}

void SSD1306Device::ssd1306_send_data_stop(void)
{
	Wire.endTransmission();
}

void SSD1306Device::setCursor(uint8_t x, uint8_t y)
{
	ssd1306_send_command_start();
	Wire.write(0xb0 + y);
	Wire.write(((x & 0xf0) >> 4) | 0x10); // | 0x10
	Wire.write((x & 0x0f) | 0x01); // | 0x01
	ssd1306_send_command_stop();
	oledX = x;
	oledY = y;
}

void SSD1306Device::clear(void)
{
	fill(0x00);
}

void SSD1306Device::fill(uint8_t fill)
{
	uint8_t m,n,o;
	for (m = 0; m < 8; m++)
	{
		ssd1306_send_command(0xb0 + m);	// page0 - page1
		ssd1306_send_command(0x00);		// low column start address
		ssd1306_send_command(0x10);		// high column start address
		ssd1306_send_data_start();
		for (n = 0, o = 0; n < 128; n++)
		{
			ssd1306_send_data_byte(fill);
      o++;
      if (o == BUFFER_LENGTH - 1)
      {
        ssd1306_send_data_stop();
        ssd1306_send_data_start();
        o = 0;
      }
		}
		ssd1306_send_data_stop();
	}
	setCursor(0, 0);
}

size_t SSD1306Device::write(byte c) {
// This function is modified to work also with 16x32 fonts for digits
//  Useful to display only numerical results in Largest Size!
//=================================================================
#ifdef FONT16X32	
 if(oledFont==2) {  

	// If "font16x32.h" contains only 10 symbols (0..9) rotated 90deg. right, then:
      ci = c - 44;  	// Only symbols ,-./0...9:  are available in 13kB file [0=char(16)]
      

     if (oledX > 112){ // long numbers are cut to max 8 digits
	   return 1;
	}
      			
	for (uint8_t j = 3; j > 1 ; j--) { 		// Send from top to bottom 2*16 bytes on rows
		ssd1306_send_data_start();
		for (uint8_t i = 0; i < 16; i++) { 	// Send 16 bytes as rows, at the same y position
			Wire.write(pgm_read_byte(&ssd1306xled_font16x32[ci * 64 + 4*i +j]));
		}
		ssd1306_send_data_stop();
		setCursor(oledX, oledY + 4-j);   	// Prepare position of next row of 16 bytes under the first one
	}

      setCursor(oledX, oledY-1);   			// Return a row higher 
	for (uint8_t j = 3; j > 1 ; j--) { 		// Send from the lower half 2*16 bytes on rows
		ssd1306_send_data_start();
		for (uint8_t i = 0; i < 16; i++) { 	// Send from top to bottom 2*16 bytes
			Wire.write(pgm_read_byte(&ssd1306xled_font16x32[ci * 64 + 4*i +j -2]));
		}
		ssd1306_send_data_stop();
		setCursor(oledX, oledY+1);   			// Relative move lower by 1 byte for last 16 bytes
	}
     setCursor(oledX+16, oledY-4);				// Move cursor for next digit
  }
#endif
//==================================================================
#ifdef FONT8X16
if(oledFont==1) { 
	if (c == '\n') {
		oledY++;
  		if (oledY > 6) {
			oledY = 6;
  		}
  		setCursor(0, oledY);
			return 1;
      }

	ci = c - 32;

	if (oledX > 120) {
		oledY+=2;
		if (oledY > 6) {
			oledY = 6;
		}
			setCursor(0, oledY);
	}
	ssd1306_send_data_start();
	for (uint8_t i = 0; i < 8; i++) {
		Wire.write(pgm_read_byte(&ssd1306xled_font8x16[ci * 16 + i]));
	}
	ssd1306_send_data_stop();
	setCursor(oledX, oledY + 1);
	ssd1306_send_data_start();
	for (uint8_t i = 0; i < 8; i++) {
		Wire.write(pgm_read_byte(&ssd1306xled_font8x16[ci * 16 + i + 8]));
	}
	ssd1306_send_data_stop();
	setCursor(oledX + 8, oledY - 1);
 }
#endif
//==================================================================
#ifdef FONT6X8
 if(oledFont== 0) { 
	if (c == '\n') {
		if (oledFont == FONT6X8) {
			oledY++;
			if (oledY > 7) {
				oledY = 7;
			}
			setCursor(0, oledY);
			return 1;
		}
	}
	ci = c - 32;
	if (oledX > 122) {
		oledY++;
		if (oledY > 7) {
			oledY = 7;
		}
		setCursor(0, oledY);
	}

	ssd1306_send_data_start();
	for (uint8_t i= 0; i < 6; i++) {
		ssd1306_send_data_byte(pgm_read_byte(&ssd1306xled_font6x8[ci * 6 + i]));
	}
	ssd1306_send_data_stop();
	oledX+=6; // we don't need to call setCursor for every character.
 }
#endif
//==================================================================
return 1;
}




void SSD1306Device::bitmap(uint8_t x0, uint8_t y0, uint8_t x1, uint8_t y1, const uint8_t bitmap[])
{
	uint16_t j = 0;
	uint8_t y, x;
	// if (y1 % 8 == 0) y = y1 / 8; 	// else y = y1 / 8 + 1;		// tBUG :: this does nothing as y is initialized below
	//	THIS PARAM rule on y makes any adjustment here WRONG   //usage oled.bitmap(START X IN PIXELS, START Y IN ROWS OF 8 PIXELS, END X IN PIXELS, END Y IN ROWS OF 8 PIXELS, IMAGE ARRAY);
 	for (y = y0; y < y1; y++)
	{
		setCursor(x0,y);
		ssd1306_send_data_start();
		for (x = x0; x < x1; x++)
		{
			ssd1306_send_data_byte(pgm_read_byte(&bitmap[j++]));
		}
		ssd1306_send_data_stop();
	}
	setCursor(0, 0);
}


SSD1306Device oled;

// ----------------------------------------------------------------------------

/*
 * SSD1306xLED - Drivers for SSD1306 controlled dot matrix OLED/PLED 128x64 displays
 *
 * @created: 2014-08-12
 * @author: Neven Boyanov
 *
 * Source code available at: https://bitbucket.org/tinusaur/ssd1306xled
 *
 */

// ----------------------------------------------------------------------------

#include <avr/pgmspace.h>

// ----------------------------------------------------------------------------

/* Standard ASCII 8x16 font */
const uint8_t ssd1306xled_font8x16 [] PROGMEM = {
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, // 0
  0x00,0x00,0x00,0xF8,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x33,0x30,0x00,0x00,0x00, // ! 1
  0x00,0x10,0x0C,0x06,0x10,0x0C,0x06,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, // " 2
  0x40,0xC0,0x78,0x40,0xC0,0x78,0x40,0x00,0x04,0x3F,0x04,0x04,0x3F,0x04,0x04,0x00, // # 3
  0x00,0x70,0x88,0xFC,0x08,0x30,0x00,0x00,0x00,0x18,0x20,0xFF,0x21,0x1E,0x00,0x00, // $ 4
  0xF0,0x08,0xF0,0x00,0xE0,0x18,0x00,0x00,0x00,0x21,0x1C,0x03,0x1E,0x21,0x1E,0x00, // % 5
  0x00,0xF0,0x08,0x88,0x70,0x00,0x00,0x00,0x1E,0x21,0x23,0x24,0x19,0x27,0x21,0x10, // & 6
  0x10,0x16,0x0E,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, // ' 7
  0x00,0x00,0x00,0xE0,0x18,0x04,0x02,0x00,0x00,0x00,0x00,0x07,0x18,0x20,0x40,0x00, // ( 8
  0x00,0x02,0x04,0x18,0xE0,0x00,0x00,0x00,0x00,0x40,0x20,0x18,0x07,0x00,0x00,0x00, // ) 9
  0x40,0x40,0x80,0xF0,0x80,0x40,0x40,0x00,0x02,0x02,0x01,0x0F,0x01,0x02,0x02,0x00, // * 10
  0x00,0x00,0x00,0xF0,0x00,0x00,0x00,0x00,0x01,0x01,0x01,0x1F,0x01,0x01,0x01,0x00, // + 11
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0xB0,0x70,0x00,0x00,0x00,0x00,0x00, // , 12
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x01,0x01,0x01,0x01,0x01,0x01, // - 13
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x30,0x30,0x00,0x00,0x00,0x00,0x00, // . 14
  0x00,0x00,0x00,0x00,0x80,0x60,0x18,0x04,0x00,0x60,0x18,0x06,0x01,0x00,0x00,0x00, // / 15
  0x00,0xE0,0x10,0x08,0x08,0x10,0xE0,0x00,0x00,0x0F,0x10,0x20,0x20,0x10,0x0F,0x00, // 0 16
  0x00,0x10,0x10,0xF8,0x00,0x00,0x00,0x00,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00, // 1 17
  0x00,0x70,0x08,0x08,0x08,0x88,0x70,0x00,0x00,0x30,0x28,0x24,0x22,0x21,0x30,0x00, // 2 18
  0x00,0x30,0x08,0x88,0x88,0x48,0x30,0x00,0x00,0x18,0x20,0x20,0x20,0x11,0x0E,0x00, // 3 19
  0x00,0x00,0xC0,0x20,0x10,0xF8,0x00,0x00,0x00,0x07,0x04,0x24,0x24,0x3F,0x24,0x00, // 4 20
  0x00,0xF8,0x08,0x88,0x88,0x08,0x08,0x00,0x00,0x19,0x21,0x20,0x20,0x11,0x0E,0x00, // 5 21
  0x00,0xE0,0x10,0x88,0x88,0x18,0x00,0x00,0x00,0x0F,0x11,0x20,0x20,0x11,0x0E,0x00, // 6 22
  0x00,0x38,0x08,0x08,0xC8,0x38,0x08,0x00,0x00,0x00,0x00,0x3F,0x00,0x00,0x00,0x00, // 7 23
  0x00,0x70,0x88,0x08,0x08,0x88,0x70,0x00,0x00,0x1C,0x22,0x21,0x21,0x22,0x1C,0x00, // 8 24
  0x00,0xE0,0x10,0x08,0x08,0x10,0xE0,0x00,0x00,0x00,0x31,0x22,0x22,0x11,0x0F,0x00, // 9 25
  0x00,0x00,0x00,0xC0,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x30,0x30,0x00,0x00,0x00, // : 26
  0x00,0x00,0x00,0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0x60,0x00,0x00,0x00,0x00, // ; 27
  0x00,0x00,0x80,0x40,0x20,0x10,0x08,0x00,0x00,0x01,0x02,0x04,0x08,0x10,0x20,0x00, // < 28
  0x40,0x40,0x40,0x40,0x40,0x40,0x40,0x00,0x04,0x04,0x04,0x04,0x04,0x04,0x04,0x00, // = 29
  0x00,0x08,0x10,0x20,0x40,0x80,0x00,0x00,0x00,0x20,0x10,0x08,0x04,0x02,0x01,0x00, // > 30
  0x00,0x70,0x48,0x08,0x08,0x08,0xF0,0x00,0x00,0x00,0x00,0x30,0x36,0x01,0x00,0x00, // ? 31
  0xC0,0x30,0xC8,0x28,0xE8,0x10,0xE0,0x00,0x07,0x18,0x27,0x24,0x23,0x14,0x0B,0x00, // @ 32
  0x00,0x00,0xC0,0x38,0xE0,0x00,0x00,0x00,0x20,0x3C,0x23,0x02,0x02,0x27,0x38,0x20, // A 33
  0x08,0xF8,0x88,0x88,0x88,0x70,0x00,0x00,0x20,0x3F,0x20,0x20,0x20,0x11,0x0E,0x00, // B 34
  0xC0,0x30,0x08,0x08,0x08,0x08,0x38,0x00,0x07,0x18,0x20,0x20,0x20,0x10,0x08,0x00, // C 35
  0x08,0xF8,0x08,0x08,0x08,0x10,0xE0,0x00,0x20,0x3F,0x20,0x20,0x20,0x10,0x0F,0x00, // D 36
  0x08,0xF8,0x88,0x88,0xE8,0x08,0x10,0x00,0x20,0x3F,0x20,0x20,0x23,0x20,0x18,0x00, // E 37
  0x08,0xF8,0x88,0x88,0xE8,0x08,0x10,0x00,0x20,0x3F,0x20,0x00,0x03,0x00,0x00,0x00, // F 38
  0xC0,0x30,0x08,0x08,0x08,0x38,0x00,0x00,0x07,0x18,0x20,0x20,0x22,0x1E,0x02,0x00, // G 39
  0x08,0xF8,0x08,0x00,0x00,0x08,0xF8,0x08,0x20,0x3F,0x21,0x01,0x01,0x21,0x3F,0x20, // H 40
  0x00,0x08,0x08,0xF8,0x08,0x08,0x00,0x00,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00, // I 41
  0x00,0x00,0x08,0x08,0xF8,0x08,0x08,0x00,0xC0,0x80,0x80,0x80,0x7F,0x00,0x00,0x00, // J 42
  0x08,0xF8,0x88,0xC0,0x28,0x18,0x08,0x00,0x20,0x3F,0x20,0x01,0x26,0x38,0x20,0x00, // K 43
  0x08,0xF8,0x08,0x00,0x00,0x00,0x00,0x00,0x20,0x3F,0x20,0x20,0x20,0x20,0x30,0x00, // L 44
  0x08,0xF8,0xF8,0x00,0xF8,0xF8,0x08,0x00,0x20,0x3F,0x00,0x3F,0x00,0x3F,0x20,0x00, // M 45
  0x08,0xF8,0x30,0xC0,0x00,0x08,0xF8,0x08,0x20,0x3F,0x20,0x00,0x07,0x18,0x3F,0x00, // N 46
  0xE0,0x10,0x08,0x08,0x08,0x10,0xE0,0x00,0x0F,0x10,0x20,0x20,0x20,0x10,0x0F,0x00, // O 47
  0x08,0xF8,0x08,0x08,0x08,0x08,0xF0,0x00,0x20,0x3F,0x21,0x01,0x01,0x01,0x00,0x00, // P 48
  0xE0,0x10,0x08,0x08,0x08,0x10,0xE0,0x00,0x0F,0x18,0x24,0x24,0x38,0x50,0x4F,0x00, // Q 49
  0x08,0xF8,0x88,0x88,0x88,0x88,0x70,0x00,0x20,0x3F,0x20,0x00,0x03,0x0C,0x30,0x20, // R 50
  0x00,0x70,0x88,0x08,0x08,0x08,0x38,0x00,0x00,0x38,0x20,0x21,0x21,0x22,0x1C,0x00, // S 51
  0x18,0x08,0x08,0xF8,0x08,0x08,0x18,0x00,0x00,0x00,0x20,0x3F,0x20,0x00,0x00,0x00, // T 52
  0x08,0xF8,0x08,0x00,0x00,0x08,0xF8,0x08,0x00,0x1F,0x20,0x20,0x20,0x20,0x1F,0x00, // U 53
  0x08,0x78,0x88,0x00,0x00,0xC8,0x38,0x08,0x00,0x00,0x07,0x38,0x0E,0x01,0x00,0x00, // V 54
  0xF8,0x08,0x00,0xF8,0x00,0x08,0xF8,0x00,0x03,0x3C,0x07,0x00,0x07,0x3C,0x03,0x00, // W 55
  0x08,0x18,0x68,0x80,0x80,0x68,0x18,0x08,0x20,0x30,0x2C,0x03,0x03,0x2C,0x30,0x20, // X 56
  0x08,0x38,0xC8,0x00,0xC8,0x38,0x08,0x00,0x00,0x00,0x20,0x3F,0x20,0x00,0x00,0x00, // Y 57
  0x10,0x08,0x08,0x08,0xC8,0x38,0x08,0x00,0x20,0x38,0x26,0x21,0x20,0x20,0x18,0x00, // Z 58
  0x00,0x00,0x00,0xFE,0x02,0x02,0x02,0x00,0x00,0x00,0x00,0x7F,0x40,0x40,0x40,0x00, // [ 59
  0x00,0x0C,0x30,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x06,0x38,0xC0,0x00, // \ 60
  0x00,0x02,0x02,0x02,0xFE,0x00,0x00,0x00,0x00,0x40,0x40,0x40,0x7F,0x00,0x00,0x00, // ] 61
  0x00,0x00,0x04,0x02,0x02,0x02,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, // ^ 62
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80, // _ 63
  0x00,0x02,0x02,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, // ` 64
  0x00,0x00,0x80,0x80,0x80,0x80,0x00,0x00,0x00,0x19,0x24,0x22,0x22,0x22,0x3F,0x20, // a 65
  0x08,0xF8,0x00,0x80,0x80,0x00,0x00,0x00,0x00,0x3F,0x11,0x20,0x20,0x11,0x0E,0x00, // b 66
  0x00,0x00,0x00,0x80,0x80,0x80,0x00,0x00,0x00,0x0E,0x11,0x20,0x20,0x20,0x11,0x00, // c 67
  0x00,0x00,0x00,0x80,0x80,0x88,0xF8,0x00,0x00,0x0E,0x11,0x20,0x20,0x10,0x3F,0x20, // d 68
  0x00,0x00,0x80,0x80,0x80,0x80,0x00,0x00,0x00,0x1F,0x22,0x22,0x22,0x22,0x13,0x00, // e 69
  0x00,0x80,0x80,0xF0,0x88,0x88,0x88,0x18,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00, // f 70
  0x00,0x00,0x80,0x80,0x80,0x80,0x80,0x00,0x00,0x6B,0x94,0x94,0x94,0x93,0x60,0x00, // g 71
  0x08,0xF8,0x00,0x80,0x80,0x80,0x00,0x00,0x20,0x3F,0x21,0x00,0x00,0x20,0x3F,0x20, // h 72
  0x00,0x80,0x98,0x98,0x00,0x00,0x00,0x00,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00, // i 73
  0x00,0x00,0x00,0x80,0x98,0x98,0x00,0x00,0x00,0xC0,0x80,0x80,0x80,0x7F,0x00,0x00, // j 74
  0x08,0xF8,0x00,0x00,0x80,0x80,0x80,0x00,0x20,0x3F,0x24,0x02,0x2D,0x30,0x20,0x00, // k 75
  0x00,0x08,0x08,0xF8,0x00,0x00,0x00,0x00,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00, // l 76
  0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x00,0x20,0x3F,0x20,0x00,0x3F,0x20,0x00,0x3F, // m 77
  0x80,0x80,0x00,0x80,0x80,0x80,0x00,0x00,0x20,0x3F,0x21,0x00,0x00,0x20,0x3F,0x20, // n 78
  0x00,0x00,0x80,0x80,0x80,0x80,0x00,0x00,0x00,0x1F,0x20,0x20,0x20,0x20,0x1F,0x00, // o 79
  0x80,0x80,0x00,0x80,0x80,0x00,0x00,0x00,0x80,0xFF,0xA1,0x20,0x20,0x11,0x0E,0x00, // p 80
  0x00,0x00,0x00,0x80,0x80,0x80,0x80,0x00,0x00,0x0E,0x11,0x20,0x20,0xA0,0xFF,0x80, // q 81
  0x80,0x80,0x80,0x00,0x80,0x80,0x80,0x00,0x20,0x20,0x3F,0x21,0x20,0x00,0x01,0x00, // r 82
  0x00,0x00,0x80,0x80,0x80,0x80,0x80,0x00,0x00,0x33,0x24,0x24,0x24,0x24,0x19,0x00, // s 83
  0x00,0x80,0x80,0xE0,0x80,0x80,0x00,0x00,0x00,0x00,0x00,0x1F,0x20,0x20,0x00,0x00, // t 84
  0x80,0x80,0x00,0x00,0x00,0x80,0x80,0x00,0x00,0x1F,0x20,0x20,0x20,0x10,0x3F,0x20, // u 85
  0x80,0x80,0x80,0x00,0x00,0x80,0x80,0x80,0x00,0x01,0x0E,0x30,0x08,0x06,0x01,0x00, // v 86
  0x80,0x80,0x00,0x80,0x00,0x80,0x80,0x80,0x0F,0x30,0x0C,0x03,0x0C,0x30,0x0F,0x00, // w 87
  0x00,0x80,0x80,0x00,0x80,0x80,0x80,0x00,0x00,0x20,0x31,0x2E,0x0E,0x31,0x20,0x00, // x 88
  0x80,0x80,0x80,0x00,0x00,0x80,0x80,0x80,0x80,0x81,0x8E,0x70,0x18,0x06,0x01,0x00, // y 89
  0x00,0x80,0x80,0x80,0x80,0x80,0x80,0x00,0x00,0x21,0x30,0x2C,0x22,0x21,0x30,0x00, // z 90
  0x00,0x00,0x00,0x00,0x80,0x7C,0x02,0x02,0x00,0x00,0x00,0x00,0x00,0x3F,0x40,0x40, // { 91
  0x00,0x00,0x00,0x00,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xFF,0x00,0x00,0x00, // | 92
  0x00,0x02,0x02,0x7C,0x80,0x00,0x00,0x00,0x00,0x40,0x40,0x3F,0x00,0x00,0x00,0x00, // } 93
  0x00,0x06,0x01,0x01,0x02,0x02,0x04,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, // ~ 94
};

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John Bradnam

141 projects • 167 followers

3S Battery Charger

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