Frequently Asked Questions (FAQ) for LED Driver

Can't find generic USB audio driver for a Samson COU1 USB microphone

Are you connected to the internet and allowing Device Manager to search Windows Update? That worked for me.As an aside, I contacted Samson support about this mic: they had a specialized driver, but it was poorly written and introduced cracks, pops, ticking noises, clipping, etc. into the recorded audio. Samson support suggested that I uninstall their driver and let windows update pick it back up -- and this worked marvelously.

Don't forget that with this mic you may need to go into recording properties and set it as your default or selected recording source, or no dice, Chicago

------

(Backlight) LED Driver maximum number of LEDs

Isn't it irrelevant how many LEDs you connect as long as the voltage is correct and the driver can supply or sink enough current?Only the string max voltage and current are relevant not the max number of LEDs.

I don't know why they specify the output in terms of the number of LEDs. Why do some ICs have multiple sink channels for separate strings when you can connect them together to increase the total current? Flexibility to increase target market. I have 2 backlight strings of 120mA eachAnd about 24-30V per channel. Check out the TI LP8862, Allegro A8502

------

LED Visible Light encoding

I found two issues that were affecting the response of the circuit:

- The CSHUNT (capacitor in parallel with the LED) that should act as ripple filter didn't allow to follow correctly the PWM. So I removed and now works as I was expecting:

- While encoding with digitalWrite() and delayMicroseconds() I was printing the iteration Serial.println(): this was making extra delays that were also affecting the output PWM.

- I tested now in the range of my requirements and it works fine: Bit_time 166 usec, including a 95% duty cycle. That means 8 usec RTZ and the circuit responds fine

------

uC platforms to consider for faster CPU and 30 GPIO pins

I would probably look into the mbed platform. You might be able to use one of their DIP modules as your "uC DIP", though it will contain the necessary surrounding peripherals as well (crystal, power, etc). While this will be significantly more expensive than buying bare microcontroller chips, it sounds like you're not producing this in mass so that shouldn't be too much of an issue.

.There is a large developer community and the hardware can definitely meet your I/O and speed requirements. Due to the readily accessible development tools these rather complex microcontrollers will still have almost no start-up time

------

Calculate resistors for LED

I'd like to connect 10 LED to the Arduino's Digital PinsYou can't.The Arduino has an absolute maximum of 40mA from a digital IO pin, and a recommended maximum of 25mA from a digital IO pin.You can't get 350-600mA out of that.For those LEDs you need either a decent transistor to switch them, along with a suitable high power resistor with good temperature coefficient, or a proper LED driver, such as the CAT4101 or similar.

You also need a power source capable of providing many amps to drive them all. At full brightness, 10 LEDs at 600mA would need 6A

------

Driving three high power RGB LEDs with PWM, from a 9v battery

If you power off 9V then consider using some of the 3W LEDs in series: -Typically red leds need about 2.5V across them so wiring three in series will need at least 7.5V then there should be some current limiting circuit that might take 0.

5V.

Typically for blue or green leds they need 3.4V across them so maybe only series together two LEDs.You might just about get enough brightness with the NCP5623 chip this way but if not you'll need a current limit circuit and mosfets. The NTD80N02 looks OK but you need to limit current into the LEDs

------

No display after updating intel HD graphics driver

Solved it myself, in the end.Long story short, fixed it by installing the ATI drivers, not the Intel ones.Steps:Used DDU to wipe all existing display drivers in safe mode. (Thanks to headkase for the recommendation.

)Installed the ATI driver instead. Apparently the ATI driver package for switchable graphics cards has both the ATI and Intel HD Graphics drivers.Ran into some errors like "inf file not found" during driver installation, bypassed that by manually extracting and pointing Device Manager to the inf file via "update driver".Two blue screens and a DDU-aided reinstall later, it somehow worked.

Ugh.

------

LED filament bulb driver

You can use a capacitor power supply where most of the voltage is dropped in a cap on the AC input side of the bridge rectifier.The losses can be very low .The cap should be a X rated type at least 250VAc .The DC side of the bridge rectifier should have a filter cap across it to prevent annoying flicker .

Place a surge limiting resistor of say 1 Kohm 5W in the AC side to protect things at turn on .The Cap supply is nothing new and it is described elsewhere.In fact some mains LED string drivers use them .

------

MOSFET only turns partially off when overheated why?

We build high-temperature circuits, and find we have to test for this phenomena in an oven, although we generally work at higher voltages. IDSS increases with temperature on all MOSFETS and will eventually reach a point where the leakage is enough to keep it hot or it runs away; that is, the heat generated by the leakage current (in your case .7 * 12 or 8 Watts) heats up the junction enough to sustain the large leakage or allow it to continue to increase. Not an academic response, but maybe there is a solid-state physicist out there who can explain why this occurs

------

Add constant current to an XL6019 module

You cannot drive 6 LEDs with 12V.With 12V in and 6 LEDs you do not need boost buck, just boost. You should use a $7 Mean Well LDB-300L boost driver rather than the CV 12V source. Its size is about 30 mm x 20mm You would need to use LEDs that have a max current of 300 mA or higher. They also have 350, 500, 600 mA models.

With a 12V input it can drive a string of LEDs with a Vf of up to 36V. The LDB-300L has a PWM dimming pin that accepts frequencies between 100 and 1,000 hz. Mean Well LED Driver Catalog

------

High speed (>30KHz) 10-bit PWM generator

Since the Arduino Due was mentioned above (and I can't comment yet), I'll mention on that here.On the Arduino Due, you can use the compare module for PWM, eg. By changing the "TOP" (what the timer counts up to - this sets the frequency) using the RC register in the AT91SAM chip, you can adjust the frequency (and resolution). To get 30 kHz, you end up having more than 10-bit resolution (with a 1:1 prescaler).I see there is also a separate PWM block in the chip. I haven't played around with that, but the datasheet should reveal more.

------

Display large decimal number using seven segments display closed

The way you've designed it, you're giving 4 bits to one display and 4 bits to the other display. That's great if you're trying to display your value in hexidecimal. (...which assumes the 7447 LED driver chip supported symbols AbCdEF.

) Otherwise you're going to need another IC which inputs 8-bit digital value and either gives you 3-digit BCD (2,4,4 wires) or can directly drive the LED segments (3x7 wires). If your number will never exceed 63, you do not need to physically wire the 3rd digit. Alternately you might find another display module which inputs 8 bits and displays a 2-3-digit unsigned decimal value.

------

Connect audio device with bluetooth dongle

It is likely you are having compatibility issues between the three devices; computer, dongle and headset. Here is what the user manual states about compatibility.Your headset is compatible with Bluetooth enabled mobile phones. It features Bluetooth version 3.0. It also works with devices featuring other Bluetooth versions that support the Headset profile (HSP), Hands-Free profile (HFP), Advanced Audio Distribution profile (A2DP) and Audio/Video Remote Control profile (AVRCP).I might note the manual focuses on mobile phones. There is a lot of discussion about this issue on Philips' forum; SHB7000 Windows 7 Bluetooth Driver Problem & SHB7000 not working on windows 7.

------

UART LED Driver using MOSFET

The drive voltage refers to the $V_mathrmGS$ at which those $R_mathrmDS$ values are reported. The maximum $R_mathrmDS$ was measured with $V_mathrmGS$ 2.75 V, and the minimum $R_mathrmDS$ was measured with $V_mathrmGS$ 5 V. Your understanding of the other parameters is correct.Your circuit will probably work, but you may encounter problems at higher baud rates. The MOSFET has a gate capacitance $C_mathrmGS$ which will distort the edges of your serial signal. This value is referred to as $C_mathrmiss$ in the datasheet, with a maximum value of 50 pF

------

How to connect LED strip to be powered by charger and batteries closed

Looks mostly fine. I'm not overly familiar with this specific charging module so correct me if I'm wrong, but it looks like there is an input to charge the batteries, but no output pins, so you would have to directly draw current from the Li-ions. It should be fine for just a 2A draw, but any higher and I would make sure I have output current protection.When your batteries drop below 4V, you wont be able to directly supply 12V any more. I would suggest a 12V regulator or some kind of LED driver to maintain constant and adequate power

------

Who's responsible for USB 3 drivers

When a USB port is located on a motherboard, or connected to directly through a cable (USB on chassis for example), then the chipset on the motherboard is responsible for the USB ports, and as such, you need to install the chipset drivers.Most likely there are installers available on the motherboard homepage, but if there isn't, then the motherboard says: we use plug and play drivers that ship with Windows. Although the manufacturer is ultimately responsible for the drivers, it can be Windows too where things stop working. But it is up to the manufacturer to contact Microsoft in these cases

------

Why the television manufacturers (Samsung, Sony, LG, so on) exceed the voltage capacity on led strips (backlight) on TV's?

Isn't 133V the open-circuit voltage? When LEDs are working, voltage should be lower.LEDs are driven by constant current sources, it's far better than using voltage regulation, because LEDs have widely varying forward voltages and they tend to have negative temperature coefficient :

Overheating reduces voltage which raises current with a constant voltage regulator which leads to even more overheating until one LED in the chain die.Here is for example the datasheet of a LED driver used in a LG TV I've repaired : mode DCDC converter"

------

Unsolvable NVIDIA & Ubuntu 16.x compatibility

I had the same problem today when I was installing Ubuntu on my new MSI GL62 laptop which has the NVIDIA Geforce GTX 960M graphics aswell. The issue, it turned out was not with the drivers as such but grub setting. I had 'nomodeset' and 'acpioff' in grub to install ubuntu with the live CD. That setting got carried on to actual installation on my laptop. I think it's the 'nomodeset' that interferes with the NVIDIA graphics drivers and not the 'acpi'. So I manually removed the options from /etc/default/grub and runand that fixed the issue.

------

Eliminating buzz or high pitch noise from PWM LED Driver? closed

You are dealing with a common problem with microcontroller-generated PWM signals: An 8-bit PWM driven at the usual clock rate can skirt the edge of audio range. Let's say the chip has an 8MHz clock. An 8-bit PWM maximum frequency is 31.25 kHz. You won't hear that, but your dog might. Add in charlieplexing: now your 30 kHz PWM is being time-shared among several LEDs, effectively lowering (into the audio range) the signal to individual LEDs.There is no easy way around this without completely changing how you approach this problem. Charlieplexing PWM dimming will scream when implemented on a small microcontroller

Artículos recomendados
On Semi Launched the LED Driver Evaluation Board Ncl30051 Circuit Solution
On semi's ncl30051 is a step-down controller with peak current control and fixed off time. It is suitable for LED driver applications. It can adjust off time, source 250mA / sink 500mA peak driving capacity, current detection accuracy at 25 ° C ± 3.2%, 3.3V level dimming input, thermal off, overcurrent protection and maximum off time protection. It is mainly used for LED backlight driver of LCD screen, LED strip lamp, LED street lamp and led bulb. This paper introduces the main characteristics of ncl30051, block diagram, typical application circuit diagram, step-down LED driver evaluation board with input 80V 350mA output, ncl30105gevb circuit diagram, bill of materials and PCB layout.Main features of ncl30051:• Constant Off Time Current−Mode Control OperaTIon• Adjustable Off TIme (0.5 [1]s to 10 [1]s)• Internal Leading Edge Blanking• Source 250 mA / Sink 500 mA Peak Drive Capability• ±3.2% Current Sense Accuracy at 25℃• Internal Startup Delay• 3.3 V Logic Level Dimming Input• This is a Pb−Free DeviceNcl30051 safety features:• Thermal Shutdown• Maximum On TIme ProtecTIon• Overcurrent ProtectionNcl30051 typical applications:• LED Backlight Drivers for LCD Panels• LED Light Bars• LED Street Lighting• LED BulbsFigure 1. Block diagram of ncl30051Figure 2. Typical application block diagram of ncl30051Figure 3. Typical application circuit diagram of ncl30051Figure 4. Outline drawing of evaluation board ncl30105gevb: input up to 80V, output 350mAFigure 5. Circuit diagram of evaluation board ncl30105gevb (1)Figure 6. Circuit diagram of evaluation board ncl30105gevb (2)Material list of evaluation board ncl30105gevb:Figure 7. Evaluation board ncl30105gevb component layout: top floorFigure 8. Evaluation board ncl30105gevb component layout: ground floor
Let's Talk About the Application of Thermal Conductive Silica Gel in LED Lighting Industry
7 Tips to Help You Sell Your Farm Fresh Eggs for More Money
Need Help Finding Kitchen Items and Sofa?
Can I Heat an Outside Chicken Coop with an Underground Heating System?
How Can I Get My Foundation Brush Clean?
My Boyfriend Wants to Get Married? We Known Each Other for a Year?
My Mom Won't Let Me Go to School Tomorrow?
Pease I Need Help Fast, I Have a Peugeot 306 1.4 Fuel Injector?
Physics Problem on Potential and Kinetic Energy...?
related searches
On Semi Launched the LED Driver Evaluation Board Ncl30051 Circuit Solution
Let's Talk About the Application of Thermal Conductive Silica Gel in LED Lighting Industry
7 Tips to Help You Sell Your Farm Fresh Eggs for More Money
Need Help Finding Kitchen Items and Sofa?
Can I Heat an Outside Chicken Coop with an Underground Heating System?
How Can I Get My Foundation Brush Clean?
My Boyfriend Wants to Get Married? We Known Each Other for a Year?
My Mom Won't Let Me Go to School Tomorrow?
Pease I Need Help Fast, I Have a Peugeot 306 1.4 Fuel Injector?