ESP-03 Testing Board

ESP-03 is the smallest ESP8266 board that have on board antenna, it can fit for many projects that have limited space, such as wearable or portable device.

This instructables show how to build a testing board for early testing the ESP-03 board before actual soldering.

• ESP-03 board is small, it is hard for soldering especially re-soldering if you want change pin connection while development
• The pin interval is 2.0 mm, it is hard to match the 2.54 mm width bread board

• a multipurpose PC board
• 2 x 7 pins male header
• 2 x 7 pins female header
• 3 x 10 k Ohm resistor
• 2 x button

1. bend both the 7 pins male header and adjust the interval width to around 2.0 mm
2. solder the bent header to the multipurpose PC board
3. stick a sponge tape in the middle for insulate between ESP board and PC board
4. cut the PC board extra part

Put the ESP-03 board on the PC board, check and adjust each header to make all can touch the ESP pin.

ESP-03 has a little jumper near Vcc pin, this is the jumper for connecting GPIO16 pin and reset pin. To facilitate the reset function for the testing board, it is required to short this jumper. Simply solder this jumper can make it.

Put the female header beside the male header and solder the pin connect one by one.

Vcc -> 10 K Ohm resistor -> EN pin

Vcc -> 10 K Ohm resistor -> GPIO16 pin (wrongly printed as GPIO18)

GND -> 10 K Ohm resistor -> GPIO15 pin

GND -> reset button -> GPIO16 pin

GND -> program button -> GPIO0 pin

connect USB to TTL cable to ESP board

TTL Tx -> ESP Rx pin

TTL Rx -> ESP Tx pin

TTL 3.3 V -> ESP Vcc pin

TTL GND -> ESP GND pin

Flash mode

1. hold program button
2. press reset button
3. release program button

Normal mode

1. press reset button