A bit help on LED cube

I am builing a 8x8x8 LED cube using my arduino mega 3560.
I am using 9x 74HC595 shift register to drive the LEDs.
the cube is haing commone cathode(in layers) and anodes in columns.
I want to ask that which transistor or MOSFET do i use to drive the layers.I have already seen instructables and other forums regarding this but I cannot get correct answer to my question.Also I will prefer to use T0-220 or TO-92 package not SMDs.Also i need a bit explanation on using them.I have already seen IRF9540 but i feel really using it I cannot have that much current.the require curret for each layer would be 64*20mA(for max brightness of LED)=1.280A

THANKS, Yash

Sorry if i have posted this on wrong place you can move it to anothor place also i will not feel bad. :slight_smile:

Layers are common cathode? Use N-channel MOSFET to sink current

Common anode? P-channel MOSFET

CrossRoads:
Layers are common cathode? Use N-channel MOSFET to sink current
http://www.digikey.com/product-search/en?vendor=0&keywords=aoi514

Common anode? P-channel MOSFET
http://www.digikey.com/product-detail/en/NDP6020P/NDP6020P-ND/1055922

I think you have already made a LED cube so u posted a MOSFET unlike to tutorial present over internet

I'm part way through my own 8x8x8 white LED cube project. I was finding that when operating in the mode of having a single LED on at any one time, I could get away without MOSFETS because the current through the LEDs was low enough to be handled by the current sinking capability of the outputs of the layer shift register.

I've still not moved away from the shiftOut command, so found myself hampered by the speed of the Arduino code. As a result, I've moved away from the strict single LED lit rule, outputting block patterns when I could. This, obviously, has an impact on the layer surrent.

I've come into a whole load of old components, and have been finding what I can use. I have many quad pack N-channel MOSFETS, called VQ1000J. They are relatively low powered, evidenced by the fact that they are in DIL packages and come with no heat-sink.

The core of my cube control circuitry is unlike what I see everyone else doing. Instead of eight shift registers to light all the columns for any given layer, thus requiring b bytes to be shifted to describe each layer, I have a shift register for controlling the layers (via the N-channel MOSFET) and one each to control the rows and aisles (think ancient church analogy). The rows and aisle are then put through an AND gate matrix, thus giving the required column condition. I can this write to the whole cube in three bytes.

My fade pattern is also controlled by masking a PWM signal with the layer pattern input.

sirius631:
I have a shift register for controlling the layers (via the N-channel MOSFET) and one each to control the rows and aisles (think ancient church analogy). The rows and aisle are then put through an AND gate matrix, thus giving the required column condition. I can this write to the whole cube in three bytes.

OK, so that's two shift registers plus 64 AND gates for the layer driver. I could be wrong, but AND gates come in quad packages, so you need 16 of them as well as the two shift registers, total 18 chips and can only light a single LED or parts of a single row or column at a time.

How is this an advantage over eight shift registers with the ability to light a layer pattern of any complexity?

Paul__B:
How is this an advantage over eight shift registers with the ability to light a layer pattern of any complexity?

It also sounds as though, instead of a 1/8 duty cycle, the leds will be on 1/64 cycle? That would make them very dim.

sirius631:
The core of my cube control circuitry is unlike what I see everyone else doing.

It also sounds as though, instead of a 1/8 duty cycle, the leds will be on 1/64 cycle? Whould that not make them very dim?

sirius631:
I've moved away from the strict single LED lit rule

...or is it a 1/512 duty cycle?

sirius631:
I've come into a whole load of old components, and have been finding what I can use. I have many quad pack N-channel MOSFETS, called VQ1000J. They are relatively low powered, evidenced by the fact that they are in DIL packages and come with no heat-sink.

See the data see bro it has max output current of 0.115A and we need

64*20mA=1.28A per layer per transistor/MOSFET for full brightness if we light up each and every LED.

How about using NTE2372 or MC34152. are they good as they can provide 1.5A maximum at normal temperature