16 PWM channel I2C FET Arduino shield PCA9685 by LEDSEE

Projects General Guidance
1

I bought one of LEDSEE's new 16 channel FET controllers to drive some high power LEDs. The details on the web page show it dealing with some high current / voltages. Detail below:

http://www.ledsee.com/index.php/en/?option=com_virtuemart&view=productdetails&virtuemart_category_id=55&virtuemart_product_id=1142&Itemid=116

Unfortunately the technical specs downloaded from the above page don't match with the sales info on the product page and state lower voltages being supported - useless for what I need.

Two questions:

  1. Has anyone else used this board and if so you do know if it runs at 12V or so to drive high power LED automotive LEDs. How did you use it - configs, pin settings, what connects to what etc...

  2. How do you wire it to a Arduino (micro) and programme it? I don't want to trust the manual as it seems like its for a generic (other product) and I always like to look through a few samples of code to see how it it implemented in real projects.

I hope someone can help as LEDSEE haven't responded to my queries.

Kind regards,

2

couple of things. first, better to use tinyurl.com to make a tiny url, or post the part number of order number, even better yet, the linnk to the data sheet.

now, about that board.....
16 channels, with 15 pairs of screw terminals. .........

it is not a shield, it is a "schield"

and there are only 8 switches

3 glaring errors on the one page

the biggest offense is that there is no data sheet.

no reason you could not use 12V for an LED, then use a dropping resistor go get power to the LED and if it goes

power => LED => Resistor = > pin,

well, the voltage on the pin will be less than 5 volts. so that part is workable.

3

@dave-in-nj.
I think one screw per output, one or more commons, and some terminals connected to other Arduino pins.
I agree with the "no datasheet" part. This is a useless product for most of us without the proper documentation and schematic diagram.

Ratbag:
I bought one of LEDSEE's new 16 channel FET controllers to drive some high power LEDs.

Seems to be a shield for short pieces of LED strip (<1Amp), or for low power LEDs.
High power LEDs need switching CC LED drivers.
Unless you don't mind the heat from a bank of current limiting resistors.

Attached is a homegrown 16-channel PCA9685 board with 16 switching CC drivers.
Very efficient (little or no heat).
Leo..

Led Driver x16.jpg
Led Driver x16.jpg1024×768 190 KB

4

Wawa:
Attached is a homegrown 16-channel PCA9685 board with 16 switching CC drivers.
Very efficient (little or no heat).
Leo..

Hi,

Thats a very neat looking pcb /driver board, wondered if you were sharing the schematic and pcb design ?

5

PM sent.

6

Wawa:
@dave-in-nj.
I think one screw per output, one or more commons, and some terminals connected to other Arduino pins.
I agree with the "no datasheet" part. This is a useless product for most of us without the proper documentation and schematic diagram.
Seems to be a shield for short pieces of LED strip (<1Amp), or for low power LEDs.
High power LEDs need switching CC LED drivers.
Unless you don't mind the heat from a bank of current limiting resistors.

Attached is a homegrown 16-channel PCA9685 board with 16 switching CC drivers.
Very efficient (little or no heat).
Leo..

Wow that is an amazing bit of work you achieved with that board! It looks like the type of board I thought I was buying!

Thank you for your advice.

7

Thanks Dave-in-nj - i'll put some comments in line below...

dave-in-nj:

  1. 16 channels, with 15 pairs of screw terminals. .........

ANSWER: there seems to be several connectors for power, GND, analogue input etc that might explain the disparity in screw count.

  1. it is not a shield, it is a "schield"

ANSWER: Indeed it is! It's a new form of board for the dyslexic market.

  1. and there are only 8 switches

ANSWER: The switches change the internal circuit resistance and work in pairs. ch 1+2 on one switch, 3+4 on another etc.

  1. the biggest offense is that there is no data sheet.

ANSWER: Yes! Not having a library of example code to study is also really annoying.

  1. no reason you could not use 12V for an LED, then use a dropping resistor go get power to the LED and if it goes power => LED => Resistor = > pin,

ANSWER: It might be designed to do this out of the box - it mentions a 12V+ LEDSTRIP setting but no clarity on how to use it...

Thanks again.

8

I stumbled across this forum after finding this shield from LEDSEE and doing a little Googling on it to find more info on it.

Wawa, I am too interested in the schematic and pcb design of your board you uploaded if you dont mind sharing it still.

Thanks in advance.

9

Wawa:
@dave-in-nj.
I think one screw per output, one or more commons, and some terminals connected to other Arduino pins.
I agree with the "no datasheet" part. This is a useless product for most of us without the proper documentation and schematic diagram.
Seems to be a shield for short pieces of LED strip (<1Amp), or for low power LEDs.
High power LEDs need switching CC LED drivers.
Unless you don't mind the heat from a bank of current limiting resistors.

Attached is a homegrown 16-channel PCA9685 board with 16 switching CC drivers.
Very efficient (little or no heat).
Leo..

Great PCB, please can I have the schematic?

I also sent you a PM resquesting the same...

Thank you! Ben

10

With regards to the library, maybe the adafruit one will help: GitHub - adafruit/Adafruit-PWM-Servo-Driver-Library: Adafruit PWM Servo Driver Library

It's for a board with the PCA9685.

PS: I know, late to the party.

11

benscammell:
Great PCB, please can I have the schematic?

The boards I make are for 1-3watt LEDs, up to six in a string.
Might not be right for the 24volt/2Amp you're talking about.
Post a link to the LEDs you have.
There might be other solutions.
Leo..