Function addition between function.

[Ian Rogers]

What LED's have you selected 3v @ 100mA

 

[koolguy]

What LED's have you selected 3v @ 100mA

my doubt is only how the chip can supply 20V if power supply is connected at 5V, that mean can we connect the supply to 20V?

 

[koolguy]

Hello,
Which led are these?

 

[Ian Rogers]

The chip doesn't supply!!! the chip sinks current... Okay! lets try and get your head around this..

If I said that the chip is a 5v device but the LED pins are 20v tolerant... So even if you had nothing but 20v on an LED pin it would still only consume the chosen mA that you had previously set... If you placed a 30v potential on the LED pin, they won't guarantee the mA...

Does that make more sense?

 

[koolguy]

Hello,
again i am confused with This what that mean 20V on LEDs how?
From Gnd it is 5V on chip how leds are on 20V?

 

[Ian Rogers]

You have to supply the voltage to the LED's.... That's what hey are telling you..

 

[koolguy]

OK, That mean it will control from gnd ok, chip sinks current
Thanks clearing doubt, We can connect string!
thanks

 

[koolguy]

Hello,
Here is P10 display kit but in pic there is no oscillator connected with the micro controller, why?
may be it has internal high speed PLL
**broken link removed**
what is Jumbo display??
http://www.acronautomation.com/led-jumbo-display-1638289.html

 

[koolguy]

Hi again,
Can you explain give some technical note on it?

 

[Ian Rogers]

On what? The chip or the P10..... I don't know the P10...

 

[koolguy]

OK, You have never used P10?
It is pitch 10, display with 16x32 LEDs and 1/4 scanning mode!
I have no idea how this work!
and some people are making card of it, how?

 

[Ian Rogers]

OK, You have never used P10?
It is pitch 10, display with 16x32 LEDs and 1/4 scanning mode!
I have no idea how this work!
and some people are making card of it, how?

What LED drivers do they use??

 

[koolguy]

What LED drivers do they use??

74hc245 octal transceiver
74hc138
74hc595
104 coded smd
102 coded smd 1k
472 coded smd 4.7k
8 pin smd p mosfet i think!!