A project log for BlinkenCat

Modding a silicone cat lamp to have a nicer rainbow fade.

marblemarble 09/23/2017 at 21:260 Comments

The cat is a LED lamp with a lithium battery cell that is to be charged via a micro USB port. With the push of a button next to micro USB port the cat can be turned on and off.

By beating the body or the base of the cat, the mode is changed. The Modes are "warm white light on", "RGB color steps" and "LEDs off". The color steps are very annoying and the goal of this project was to replace this with pleasant color fading.

On the base of the lamp is the main PCB which is single sided and holds basic components for battery charging and protection, the main IC which does all the smarts, some analog circuitry for the "beating sensor", transistors and resistors for the LEDs, and the LEDs themselves - four warm white ones and four RGB ones. Each color is connected in parallel.

The beating sensor is a piezo element which is held in the middle of the base.

Under the main PCB is the battery and an interfacing PCB which is connected via a 4 leads cable and holds the USB port, a switch and a LED which blinks when charged.

The main IC does everything. It has contacts going in for the power, the charge status and the sensor and going out for the four colors and the charging status LED. Some pins are not used. Here you can see the footprint after removal and cleanup.

In the picture the upper left pin is pin 1.

2Charge Status INNC13
3Piezo INCharge Status LED OUT12
5Warm White OUTBlue OUT10
6Button INRed OUT9
7NCGreen OUT8