ESP8266 Community Forum

I brought a piglow for my raspberry pi and was wondering about running it on the esp.
I see that it requires 5V to drive the leds but I'm worried about 5V hitting the esp8266-01

This show the i2c at 3v3 but I'm still not sure.
Is it safe or will it damage the esp?

So use a level shifter between 'em.

http://www.aliexpress.com/item/Promotio ... 88659.html

The Raspberry Pi is a 3.3V device as well and not 5V tolerant. So if it's designed to work with a Raspberry Pi, the voltage level should be compatible with the ESP as well, without a level shifter.
While eagle part for IC1 is horrible, you can tell with some guess work that pin 3 should be VDD and is connected to 3V3 on the Pi. The I2C lines should therefore also have 3.3V max.
The 5V line is only used to drive the LEDs (3.3V is to low for some blue or white LEDs) and IC1 is probably designed to act as sink for LEDs connected to a higher voltage.