Moderator: pebe
pebe wrote:I’ve looked through the links and the data sheets for the various components you mentioned but I am having difficulty sorting the wheat from the chaff in your posting.
Am I right in assuming that the Typhon controller has nothing to do with the problem and what you are actually trying to do is use the PWM output from an Arduino to control the output voltage of the Meanwell SMPS by means of a varying analogue voltage of 10V max?
Is the Arduino fed from a 5V regulator, and if so what is the input voltage to the regulator?
Thanks for sharing that. Regarding the 10v side is definitely different looking on the oscilloscope, (not a clean square wave), but oddly, it works just fine on the 10V PWM drivers, so we never really looked into it.
Thanks!
Jeff
pebe wrote:
Am I right in assuming that the Typhon controller has nothing to do with the problem and what you are actually trying to do is use the PWM output from an Arduino to control the output voltage of the Meanwell SMPS by means of a varying analogue voltage of 10V max?
Is the Arduino fed from a 5V regulator, and if so what is the input voltage to the regulator?
pebe wrote:I’ve looked through the links and the data sheets for the various components you mentioned but I am having difficulty sorting the wheat from the chaff in your posting.
Am I right in assuming that the Typhon controller has nothing to do with the problem and what you are actually trying to do is use the PWM output from an Arduino to control the output voltage of the Meanwell SMPS by means of a varying analogue voltage of 10V max?
Is the Arduino fed from a 5V regulator, and if so what is the input voltage to the regulator?
1. The Arduino shown in your first posting is actually a part of the Typhon controller
2. The Typhon outputs 5V and 10V PWM signals.
3. The Meanwell can be controlled by either 0V-10V analogue signals, or 10Vpp PWM signals.
Or have I missed something?
No, that was the "rumor" and I believe it would work w/ a "normal" 10v PWM signal where the Voltage is pulsed.. not the ground is "pulsed".
either way it is irreverent to this discussion since it doesn't work.
MeanWell LPF-60D-48 is better as it offers dimming via 1~10Vdc or PWM signal or resistance unlike the ELN-60-48D/P .
Your situation is that the 5V PWM output of the Typhon works as a "source" and the 10V output as a "sink". Briefly explained, the 5V PWM switches on/off the +5V and the ground is fixed. With the 10V PWM signal, the +10V is fixed and the ground is switched on/off.
When you connect the low pass RC filter to the 5V PWM to smooth it out it works since the switching 5V charges the capacitor to a certain point depending on the PMW ON duration.
On the other hand with the 10V PWM, since the +10V is fixed the RC low pass filter have no effect. There is no variable voltage to smooth out.
I guess that with a PNP transistor, the 10V PWM "sink" output can be converted to a "source" output. I have not done this, it is just a pausible solution to try.
pebe wrote:I wish I had known that there were two different ELN versions at the outset, because there is nothing in the block diagram of their data sheet that would imply there is a difference. In fact, the data sheets for both the ELN and Typhon are very vague; OK if you are only wiring them up, parrot fashion, but pretty useless if you are trying to do what you are doing.
However, all is not lost. I think you need to confirm that the ELN is working correctly by connecting a 9V battery to the DIM+ and DIM- pins and check that it gives 90% output. If that is OK then we need to establish if those pins draw current from the battery. Most complex ICs these days use MOS transistors internally which have a very high input resistance, so it is only necessary to provide voltage – not current.
pebe wrote:To prove the point, fit a 100K resistor between the +ve of the 9V battery and the DIM+ input pin and see if the output is still the same.
Try that, and depending on the results we can proceed from there.
high input resistance, so it is only necessary to provide voltage – not current.
The ICL7660 and ICL7660A contain all the necessary
circuitry to complete a negative voltage converter, with the
exception of 2 external capacitors which may be inexpensive
10μF polarized electrolytic types. The mode of operation of
the device may be best understood by considering Figure
12, which shows an idealized negative voltage converter.
Capacitor C1 is charged to a voltage, V+, for the half cycle
when switches S1 and S3 are closed. (Note: Switches S2
and S4 are open during this half cycle.) During the second
half cycle of operation, switches S2 and S4 are closed, with
S1 and S3 open, thereby shifting capacitor C1 negatively by
V+ volts. Charge is then transferred from C1 to C2 such that
the voltage on C2 is exactly V+, assuming ideal switches and
no load on C2. The ICL7660 approaches this ideal situation
more closely than existing non-mechanical circuits.
Users browsing this forum: No registered users and 21 guests