I have this documented in various lights at various total output figures. Here is the test circuit I used to check how long it takes for the circuit to draw a stable mA through the LED:. Would the response be faster if the pwm voltage is 3. According to the graph posted by ChiggerPepi: It supplies mA per chip as long as the input and output voltage is within the specified range. Nah, that can’t be true. Off to the races!
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That is, Turn-on time: So if you want control over the lower ranges of duty cycle, you need to reduce the PWM frequency. That is how LED efficiency works. Does a Hz monitor produce any flicker — no.
However, assuming that the AMC is a feedback based current control system, you must consider the time that the device takes to settle to a stable constant current output.
That is not a good way to drive the AMC as the brightness will suddenly decrease in the lower ranges of duty cycle. Here is the test circuit I used to check how long it takes for the circuit to draw a stable mA through the LED: Thanks for the info.
The Chips turn on and off at high frequency. It supplies mA per chip as long as the input and output voltage is within the specified range.
AMC7135 PWM LED control – works?
Off to the races! Assuming that the supply voltage is under 6V, the setup can drive a single am7135 white power LED easily with minimal component count and no current sense resistor. So if chips are stacked 3 qmc7135 or more, does that indeed create other limiting factors?
How fast can you run the PWM? To see how this relates to brightness, you can approximate by using this graph: According to the graph posted by ChiggerPepi:. Is that because of losses in the additional chips?
AMC PWM LED control – works at what frequencies?
PWM control will not be effective over all duty cycles. What is the effect of having more or less of the AMC chips? Please look at the chart I posted above, and pay attention to what it means. Thus, if you have 3, your LED will be given mA.
AMC7135 – DC LED Driver CC
If you have the space for multiple boards, use ajc7135 and don’t use more than 8 chips each. As in this screenshot, the duty cycle is at its minimum possible here. But of course the numbers are constantly shifting, dropping with time and heat and battery loss. The input is very high impedance and so any microcontroller that outputs a 3. According to the graph posted by ChiggerPepi: AMC is a current ac7135.
Excellent info for a newbie. It did not seem to make any huge difference. Here is the test circuit I used to check how long it takes for the circuit to draw a stable mA through the LED:. Three Tanna leaves amc71355 give him life, nine to give him movement.
AMC – DC LED Driver CC  : Sunrom Electronics/Technologies
Even xmc7135 you a headache. AMC chips are current limiters. The light I saw at has different configs available and those I mentioned above has 2 groups and can be switched to 3 modes or 5 modes.
You can of course go higher, but it will reduce smoothness in brightness control. Apologies for my terrible drawing skills! If you make the frequency so high that the current sink cannot turn on properly, you will lose on your full potential power that can be delivered to the LED, ajc7135.