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Hello, What is the difference between Parts L9826 and Parts E-L9826？ I can not see the difference between them from the datasheets. Thank you in Advance
Hello,
What is the difference between Parts L9826 and Parts E-L9826？ I can not see the difference between them from the datasheets.
Thank you in Advance
Read lessHello, I am new to STM32 and trying to learn exciting stuff. I want to light a single LED from my WS2812B strip. For example, I’ll choose the 6th LED on my computer, and the 6th LED on the strip will light ...Read more
Hello,
I am new to STM32 and trying to learn exciting stuff. I want to light a single LED from my WS2812B strip.
For example, I’ll choose the 6th LED on my computer, and the 6th LED on the strip will light up.
But I am not sure where to start. How can I access to single LED address? And how to get it to work with STM32?
Thanks in advance.
Read less
Welcome, to the community! The question of WS2812 has already been discussed here many times. The thread How to use HAL DMA to generate PWM on P- NUCLEO- WB, for example, also deals with it and refers to a Github driver from Tilen Majerle and a HAL example from Martin Willner. Maybe that will help yRead more
Welcome, to the community!
The question of WS2812 has already been discussed here many times. The thread How to use HAL DMA to generate PWM on P- NUCLEO- WB, for example, also deals with it and refers to a Github driver from Tilen Majerle and a HAL example from Martin Willner.
Maybe that will help you?
Regards
Vikas
See lessI’ve read quite a bit about needing a resistor when powering a 5 mm LED from an esp32 GPIO pin, still, other experts say that if a LED is powered right, it will not need a resistor at all will ...Read more
I’ve read quite a bit about needing a resistor when powering a 5 mm LED from an esp32 GPIO pin, still, other experts say that if a LED is powered right, it will not need a resistor at all will not burn out.
1. Is it as easy as purchasing a LED that’s powered properly for an esp32 GPIO pin so that it will not probably burn out in a reasonable amount of time( years)?
2. Still, what’s the current on each GPIO pin? ( I know that the voltage on each GPIO pin is 3, If so.3 V)
3. Rather than adding a resistor, I can add a second LED parallel to add resistance and meet the power requirements, right?
Thanks!
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The maximum power per pin is 40mA. You shouldn't push more than 150 mA through all your output pins( and probably less than that to avoid overheating). You can find the correct resistor value using any led resistor calculator online and the datasheet for your led. I do not see how parallel resistorsRead more
The maximum power per pin is 40mA. You shouldn’t push more than 150 mA through all your output pins( and probably less than that to avoid overheating). You can find the correct resistor value using any led resistor calculator online and the datasheet for your led. I do not see how parallel resistors will be useful if you’re powering directly through the pin, and you do not have to get the exact resistance calculated. However, you should have a transistor gating a separate power supply for the light, If you need more than milliamps.
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What’s the purpose of the internal low-side switch in LED5000? Is it a synchronous converter? If so, also why is an external Schottky shown in the application diagrams?
What’s the purpose of the internal low-side switch in LED5000? Is it a synchronous converter? If so, also why is an external Schottky shown in the application diagrams?
Read less
Yes, it works in synchronous mode. still, after the low-side FET has been switched off, there's always a specific dead time while the inductor still drives current. That current would flow through the body diode of the low-side FET, reducing effectiveness and increasing the radiated noise. This behaRead more
Yes, it works in synchronous mode.
still, after the low-side FET has been switched off, there’s always a specific dead time while the inductor still drives current. That current would flow through the body diode of the low-side FET, reducing effectiveness and increasing the radiated noise. This behavior can be improved by using a Schottky that takes over the current during the dead time.
When your question is answered, please close this content by choosing Select as Best. This will help other users find that answer faster.
Good luck!
See lessWe’re using the L6920 to drive a 1-watt LED. We’re trying to apply the under voltage cut-off ( lockout) too. We chose the values of the voltage ground connected to the LBI pin similar that the value that comes to say ...Read more
We’re using the L6920 to drive a 1-watt LED.
We’re trying to apply the under voltage cut-off ( lockout) too. We chose the values of the voltage ground connected to the LBI pin similar that the value that comes to say 3V. Still, the IC didn’t shut off at 3V.
We also tried connecting the LBO to Vout with a 200K resistor in between. Even this didn’t work.
Can someone help apply this circuit?
Thanks!
Hi Ashish, However, you would notice that LBI input is connected to LBO output and that's the only purpose of this input, If you look into the block diagram of L6920 in its datasheet. LBI input doesn't shut down the output! Still, you need to use LBO output to shut down accordingly, If you require tRead more
Hi Ashish,
However, you would notice that LBI input is connected to LBO output and that’s the only purpose of this input, If you look into the block diagram of L6920 in its datasheet. LBI input doesn’t shut down the output!
Still, you need to use LBO output to shut down accordingly, If you require to shut down the output.
Hello I’m developing an operation that does led control with a button, I use a counter for this, but every time I hold the button, the counter increases further than 1 So indeed if I hold the button down, I want ...Read more
Hello
I’m developing an operation that does led control with a button, I use a counter for this, but every time I hold the button, the counter increases further than 1 So indeed if I hold the button down, I want it to increase once.
Read lessPerhaps you should debounce the button, as mechanical buttons bounce, i.e. may produce more than one pulse per button press. There are several techniques to do that, one of the easiest is to connect some small capacitor in parallel to the button, which together with the pull resistor forms some lowRead more
Perhaps you should debounce the button, as mechanical buttons bounce, i.e. may produce more than one pulse per button press.
There are several techniques to do that, one of the easiest is to connect some small capacitor in parallel to the button, which together with the pull resistor forms some low pass filter. The time constant of that filter should be slightly lower than the period of the maximum speed to press that button(e.g.100.200 ms). You’ll find this solution also at the NUCLEO or DISCOVERY boards.
See lessHi everyone I’m going to use STLD40D Driver IC for my TFT LCD. For driving LCD backlight, I’v chosen this Driver from ST. But I can’t figure out the function theory of this driver. could you please explain for me the STLD40D ...Read more
Hi everyone
I’m going to use STLD40D Driver IC for my TFT LCD. For driving LCD backlight, I’v chosen this Driver from ST. But I can’t figure out the function theory of this driver.
could you please explain for me the STLD40D function theory and how to use that?
thank you in advance.
Read lessWell, the STLD40D is a boost converter. The function is also described in the data sheet, section5.1. It must be taken into account that the converter not only has a min off time, but also a maximum on time. The switch- on moment is particularly interesting firstly there's no FB signal, so the powerRead more
Well, the STLD40D is a boost converter. The function is also described in the data sheet, section5.1.
It must be taken into account that the converter not only has a min off time, but also a maximum on time.
The switch- on moment is particularly interesting firstly there’s no FB signal, so the power stage is switched on( SW to GND), which charges the boost inductor. As there isn’t yet enough affair voltage to drive a current through the LEDs, pin FB remains zero. still, the maximum on time now kicks in and switches the power stage off again, whereby the energy stored in the boost inductor is delivered to the LEDs at a high voltage and results in a corresponding current and a signal to FB. From now on, FB can regulate normally.
Dear All, I want to develop 18W LED bulb in A65 Housing pls suggest me…
Dear all, i am facing one technical issue regarding LED CHIP 2835 found 1 led burn out of 20Nos. in a single light. What can be happens. pls help me. in same product found driver having no issue.
Dear all,
i am facing one technical issue regarding LED CHIP 2835 found 1 led burn out of 20Nos. in a single light. What can be happens. pls help me. in same product found driver having no issue.
Read lessI’ve 36 leds on my board. I’ll connect dimmer my board. How can i adjust leds brightness with dimmer? Because i need to manage 36 output pins. How can i do it?
I’ve 36 leds on my board. I’ll connect dimmer my board. How can i adjust leds brightness with dimmer? Because i need to manage 36 output pins. How can i do it?
Read lessYou can DMA to the io pins (using a indirect buffer, transferring to GPIO output register). I controlled 48 Leds (16 RGB Leds) this way using a STM32L4(100 LQFP package). But this was to give independent brightness situations to each individual Led. But if all Leds are dimmed together (synchronised)Read more
You can DMA to the io pins (using a indirect buffer, transferring to GPIO output register). I controlled 48 Leds (16 RGB Leds) this way using a STM32L4(100 LQFP package). But this was to give independent brightness situations to each individual Led.
But if all Leds are dimmed together (synchronised), also you probably only need a single FET to sink all the Leds current, and use that FET to control the brightness (PWM)
See less
There's no technical difference between L9826 and E-L9826. At the time, the version with the prefix E- indicated the more environmentally friendly Eco version, which has been standard for a long time. still, please mark this thread as answered by selecting Select as best, as also explained then, IfRead more
There’s no technical difference between L9826 and E-L9826. At the time, the version with the prefix E- indicated the more environmentally friendly Eco version, which has been standard for a long time.
still, please mark this thread as answered by selecting Select as best, as also explained then, If the problem is solved. This will help other users find that answer faster.
See lessRegards