The board’s MOSI pin connects to the DI pin on the LED strip, and SCLK connects to the CI pin.
below is pictures of offline wiring connection and online wiring connection
2015年12月10日星期四
How to connect Digital Addressable RGB LED strip to the Raspberry Pi, offline wiring connection, online wiring connection
Interfacing sfleds's Digital Addressable RGB LED strip to the Raspberry Pi is super simple, requiring just a few connections between the board, strip and a DC power jack.
The board’s MOSI pin connects to the DI pin on the LED strip, and SCLK connects to the CI pin.
below is pictures of offline wiring connection and online wiring connection
The board’s MOSI pin connects to the DI pin on the LED strip, and SCLK connects to the CI pin.
below is pictures of offline wiring connection and online wiring connection
2015年12月3日星期四
APA102 RGB+White LED STRIP
By Shenzhen Shining Future LED Technology Co., Ltd.
RGB+White APA102 LED STRIP
Working Voltage: DC5V
Led QTY: 60leds/M
(30pcs RGB SMD5050 APA102 LED+ 30pcs White SMD5050 APA102 LED)
Power: Max 18W/M
Led Type: SMD5050
IC Type: APA102 Chip Built In RGB & White LED
Dimension: 5000mm*14.0mm*4.0mm (IP67 waterproof)
5000mm*12.0mm*3.0mm (IP65 waterproof)
5000mm*12.0mm*2.5mm(non-waterproof)
Pixel QTY: 60pixels/m ,each led addressable
PCB Color: White or Black color
Brightness Level: 256 level
Emitting Color: RGB color + White color
Emitting Angle: 160 Degree(120 Degree also available)
Waterproof IP grade:silicon tube IP67/glue sealing IP65/Non-waterproof
2015年12月2日星期三
5050 APA102 APA104 White LED strips with addressable LEDs
Nowadays, more and more new bulid in ic RGB led chip is come out , our company develop a new White bulid in IC led chip ,They are APA102 APA104 WHITE LED CHIP . About white color , can be warm white , cool white , Nature white , Pure white . and now, they are very hot sales , can make amazing effection.
video of them is on the following
https://www.youtube.com/watch?v=hvYHcm9yTWQ
Datasheet of APA102 White led
http://www.sfleds.com/Blog/150.html#.Vl_0dy6MW1Y
Datasheet of APA104 WHITE LED
http://www.sfleds.com/Blog/159.html#.Vl_0gi6MW1YA
video of them is on the following
https://www.youtube.com/watch?v=hvYHcm9yTWQ
Datasheet of APA102 White led
http://www.sfleds.com/Blog/150.html#.Vl_0dy6MW1Y
Datasheet of APA104 WHITE LED
http://www.sfleds.com/Blog/159.html#.Vl_0gi6MW1YA
the difference between apa102 ap104 led strip and ws2812b ws2811 led strip
Firstly you should know what is APA102 chip/APA104 chip/WS2812B chip, more details, pls click below tag for reference
APA102 Chip APA104 chip WS2812B chip
APA102 led strip
(price: linda@sfleds.com)
"I contrast to the very timing-sensitive one-wire protocol of the WS2812,
the APA102 uses a standard two wire SPI protocol – one clock line and one data line.
Each LED has two inputs and two outputs which can be daisy chained. At the first
sight this may seem wasteful, but it has the advantage of being supported by standard
microcontroller periphery and it is insensitive to timing variations. Due to the critical
timing requirement it is not possible to control the WS2812 from SOCs with
multitasking operating systems, such as the Raspberry Pi. This should not be an issue
with the APA102. Furthermore, the data can be transferred at an almost arbitrary
clock rate. I was able to control the LEDs with 4 MHz SPI clock without any hitch. It
appears that the maximum speed is mainly limited by the parasitics of the wiring. The
data format is shown below.
encoding is indistinguishable from a LED set to maximum brightness and will simply
be forwarded to the next LED. In my experiments, omitting the end frame did not
have any impact.
One interesting addition is the “global” field for each LED, which allows to control
the brightness of the LED in 32 steps from 0 to 31. When trying different parameters,
I was quite surprised to observe that the LEDs did not show any visible
pulse-width-modulation (PWM) flicker at all when the global brightness was set to 31.This is quite different from the WS2812, which shows visible PWM flicker when
moving the LEDs.
Interestingly, the APA102 started to flicker once I set the global brightness to 30 or
below. To understand what was going on, I hooked up my scope to the power rails.
When the LEDs are turning on, they draw significantly higher current which leads to
a drop in voltage across the power rails. I previously used a similar method to
investigate the inner workings of candle flicker LEDs.
The picture above shows the current modulation for RGB=255,255,255 and the
global brightness set to 16 (50%). The pulse width modulation is clearly visible in
the voltage signal at a frequency of 580 Hz, very similar to the 430 Hz of the
WS2812.
Next, I set the RGB value to 128,128,128 and kept the global brightness at 50%. The
result is shown above. Two PWM modulation schemes are superimposed in this
configuration. The global brightness is still modulated at ~582 Hz, while RGB value
is modulated at an approximately 32 times higher frequency, 19.2 kHz. This
frequency is significantly above the flicker fusion threshold, even when moving the
LED around, leading to an apparent constant brightness.
The very high PWM frequency is a pretty nice feature of these LEDs. In combination
with the higher update speed due to the SPI interface, they should be much better
suited for persistance-of-vision applications than the WS2812.
In summary, the APA102 show significant promise compared to the de-facto standard
APA102 Chip APA104 chip WS2812B chip
APA102 led strip
(price: linda@sfleds.com)
(Left is WS2812B)
Below all analysis is get from our customer:
"I contrast to the very timing-sensitive one-wire protocol of the WS2812,
the APA102 uses a standard two wire SPI protocol – one clock line and one data line.
Each LED has two inputs and two outputs which can be daisy chained. At the first
sight this may seem wasteful, but it has the advantage of being supported by standard
microcontroller periphery and it is insensitive to timing variations. Due to the critical
timing requirement it is not possible to control the WS2812 from SOCs with
multitasking operating systems, such as the Raspberry Pi. This should not be an issue
with the APA102. Furthermore, the data can be transferred at an almost arbitrary
clock rate. I was able to control the LEDs with 4 MHz SPI clock without any hitch. It
appears that the maximum speed is mainly limited by the parasitics of the wiring. The
data format is shown below.
NE
Dream Color APA104 LED Strip:http://www.sfleds.com/products/shopmore.asp?id=83#.Vl_IXC6MW1Y
Each update consists of a start frame of 32 zeroes, 32 bits for every LED and an end
frame of 32 ones. I am not sure what the “End Frame” is good for, since itsencoding is indistinguishable from a LED set to maximum brightness and will simply
be forwarded to the next LED. In my experiments, omitting the end frame did not
have any impact.
One interesting addition is the “global” field for each LED, which allows to control
the brightness of the LED in 32 steps from 0 to 31. When trying different parameters,
I was quite surprised to observe that the LEDs did not show any visible
pulse-width-modulation (PWM) flicker at all when the global brightness was set to 31.This is quite different from the WS2812, which shows visible PWM flicker when
moving the LEDs.
Interestingly, the APA102 started to flicker once I set the global brightness to 30 or
below. To understand what was going on, I hooked up my scope to the power rails.
When the LEDs are turning on, they draw significantly higher current which leads to
a drop in voltage across the power rails. I previously used a similar method to
investigate the inner workings of candle flicker LEDs.
The picture above shows the current modulation for RGB=255,255,255 and the
global brightness set to 16 (50%). The pulse width modulation is clearly visible in
the voltage signal at a frequency of 580 Hz, very similar to the 430 Hz of the
WS2812.
Next, I set the RGB value to 128,128,128 and kept the global brightness at 50%. The
result is shown above. Two PWM modulation schemes are superimposed in this
configuration. The global brightness is still modulated at ~582 Hz, while RGB value
is modulated at an approximately 32 times higher frequency, 19.2 kHz. This
frequency is significantly above the flicker fusion threshold, even when moving the
LED around, leading to an apparent constant brightness.
The very high PWM frequency is a pretty nice feature of these LEDs. In combination
with the higher update speed due to the SPI interface, they should be much better
suited for persistance-of-vision applications than the WS2812.
In summary, the APA102 show significant promise compared to the de-facto standard
WS2812:
They can be controlled with a standard SPI interface. No critical timing
required and much faster than the one wire protocol.
They have an extremely high PWM frequency, allowing flicker-free POV
applications.
They are available in a special package with better heat sinking."
Posted by Linda Tan
http://www.sfleds.com
They can be controlled with a standard SPI interface. No critical timing
required and much faster than the one wire protocol.
They have an extremely high PWM frequency, allowing flicker-free POV
applications.
They are available in a special package with better heat sinking."
Posted by Linda Tan
http://www.sfleds.com
2015年12月1日星期二
PixelPusher BetterPixel 72LED/M Strip, IP67
The PixelPusher BetterPixel LED strip utilizes a new LED package called the APA102. The APA102 has controlling circuitry built into the LED package itself which removes the need for external components. The APA102 features 4 wire signaling unlike other all in one packages, and has much more robust signaling IP67: Suitable for immersion to one meter (three feet), this strip is sealed inside a silicone tube, and comes with mounting clips. These LED strips are five metres long , just over 15 ft. They can be cut at single LED intervals and rejoined by soldering. There are 72 LEDs per metre. Each pixel is individually controllable. What are the width's of the strips? IP67 are approx 9/16" wide, 5/32 thick. IP67 is encased in a continuous high-temperature silicone tube, and IP68 is set in solid silicone. The strips are flexible but must not be kinked; the minimum bend radius is about three inches. The strips may be daisychained, but performance suffers. We get much better performance by driving them in parallel. You can daisy chain shorter segments if you want but we recommend a max of 480 pixels on any one controller port. Each controller has eight ports. More silicone sealant is recommended if these strips will be used outdoors. More information about the PixelPusher is available at www.sfleds.com
LED strip repair kit - for APA102 Dotstar strips or WS2812B led strip
Working with digital LED strips, and want to cut them into smaller pieces? It can be a huge pain to solder wires back on, so we developed this LED strip repair kit to make things stronger. Solder one of the included reinforcement shims to the end of your strip, and never have a bad connection again!
This kit is compatible with the following strip types:
- APA102 Dotstar LED strips buy from www.sfleds.com
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