Search results

Search Forums New Posts
  1. dave9

    PWM setup

    Yes either of those should work for 12 LEDs in series including the 4 you already have, which one depending on whether you want 300mA or 900mA. Keep in mind that those heatsinks were listed for 1W/3W/5W LEDs, meaning one 5W, while 12 LEDs at 900mA is going to be higher than 5W per heatsink if...
  2. dave9

    PWM setup

    I am not sure if that one will work or not because it's cutting it close, with a max voltage of 10V and your LEDs could be right near their upper Vf range at 900mA drive current. It should work for at least 3 in series. If you can dig up a proper datasheet for the LEDs with a voltage vs...
  3. dave9

    PWM setup

    Those won't work, are just 12VDC power supplies, do not regulate current. I mean you could use one, then a series resistor or another driver module like the one that's blown, except we didn't really determine that it is suitable at 12.0V input for those 4 LEDs in series. I do not understand...
  4. dave9

    PWM setup

    Oh well, at least it wasn't an expensive driver. What I would do now, is get one that can operate from 120VAC and not use the old 12.6V PSU, which should greatly increase the efficiency. Without looking around for the best price, I mean something similar to the following "10W 3-4x2(3)W 600mA...
  5. dave9

    Woo-Woo Biocompatible Frequencies

    Flac on an old phone repurposed as a headphone driver FTW.
  6. dave9

    The Best and Cheapest way to clean Rosin Flux for your Board.

    It is late so I may have misunderstood your post. If so, I apologize. Alcohol does fine cleaning rosin core flux for me. Is this a board you soldered yourself and are sure it is rosin core flux, or is this a board that someone else produced and it's a water soluble flux and you need mild...
  7. dave9

    How do I rig up a battery charger?

    Old power tool chargers, I would seek at local pawn shops for a major brand like Dewalt, or if the pawn shop won't split up a kit and you don't want the rest, then eBay.
  8. dave9

    PWM setup

    That's not a problem. It is set up to output 700mA for as many LEDs as you want to attach, up to a series of LEDs whose sum forward voltage does not exceed 28VDC, and as mentioned previously your PSU input voltage must be a few volts (2V to 3V) above that. Measure the circuit. Measure the...
  9. dave9

    PWM setup

    It might have helped if you had provided specs for the driver and/or linked to it. There are versions of this board with default drive at 700mA without any PWM input, and some at 300mA, and possibly other current levels up to the max the U1 regulator IC can handle. It appears to determine...
  10. dave9

    I want to know about this UPS transformer with 7 wires and how to get maximum power from it.

    I would put it back in the UPS and buy a battery since your father wanted an UPS, and make getting a multimeter a priority if you want to fiddle with electrical/electronics. However before buying a 12V battery you could hook two of your 6V in series to achieve 12V for testing the UPS, provided...
  11. dave9

    Help! DC Automatic Voltage Regulation

    By using a micro-controller designed to regulate voltage and supplying the supporting components needed to do that? It might be easier if you just started out by telling us exactly what you're trying to do. What appliance, what input voltage, what output voltage (and current), and why you...
  12. dave9

    Organic LEDs...

    I've never seen any. What would you use them for? Since it's through-hole, the thinness doesn't seem a benefit and they have shorter life at higher cost, are more useful in an indicator panel array rather than a single point or general light source. I'm not understanding the benefit of a tiny...
  13. dave9

    Help identify the part

    Sometimes it is easier to identify a component, or at least determine an equivalent component, by looking at its placement in the circuit, and if the circuit still works, measuring what it is doing. In some cases that could mean if connected to an IC, you look up the datasheet for it and look...
  14. dave9

    Like new treadmill has dead console. Was working until I unhooked it for transport

    That type of reset breaker/switch often doesn't seem to do anything unless you have a current overload that trips it. As kellys_eye mentioned it should have continuity between the two pins. Considering the amount of force that was needed to pull latching connectors off and bent the pins, I...
  15. dave9

    How this forum came to be

    Probably the same as many forum oriented sites. Several people wanted it and one of them was motivated enough to DO it. I don't know when it started but another factor may be that old timers used to use usenet but then ISPs stopped offering it (*free with an ISP plan*) and usenet was quite...
  16. dave9

    Lithium ion cell equivalents

    They're definitely in series to reach their 28V claim, just using 4.0V instead of the prior convention of 3.6V/cell. The problem with a battery like that is to get something good instead of old, low capacity, low current, or fake, then the cells are going to cost a premium. Different cell size...
  17. dave9

    Battery pack diy advice please

    Doubtful, as it is it would be a boost 3.(n)V to 5.0V, but if you ran them in series it would need a buck ~7V to 5.0V circuit instead. If you wanted to replace the PCB with a buck PCB, carve up the casing to electrically put the cells in series, cut out a new USB socket hole since it's unlikely...
  18. dave9

    SMD Component Identification Assistance

    Any n-channel SOT23 mosfet rated a fair amount over the single LED strand drive current, which I don't know (but you could measure, but don't really need to) so above the PSU 0.83A. They come in much higher currents than 1.4A but that should work.
  19. dave9

    Naze32 flight controller Repair

    https://www.digikey.com/product-detail/en/taiwan-semiconductor-corporation/B0530WS-RRG/B0530WSRRGCT-ND/7357154
  20. dave9

    Wire a mag drill motor

    The owners manual states you can call 1-800-SAWDUST No, I'm not kidding...
Top