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Hey csshih, Sent you a Pm. I need your help asap on this! Thanks!

I'm interested in getting in the next round. :)

Oh man!!! I'm scrounging everything I got together now so I can get one of these! EDIT: scrounged enough :) ORDERED!

Hey, sorry if I'm late to the table, but a while ago I picked up the 504b host and just today got around to machining the heatsink. The heatsink fits snug in the main body and it has a slight shoulder so that as you screw the head of the host down, it tightens the heatsink down onto the shoulder...

Was ordering some more LT1185 LDO regulators that I use for various things... came across a this gem LT1083 LDO high output regulator. What impressed me at first was the high current output with only 3 pins! LT1083 - 7.5A, 5A, 3A Low Dropout Positive Adjustable Regulators - Linear Technology...

It's not perfect, but I think it's satisfactory. End result, I've got 600mA to each diode. I am running them in parallel with a current driver set to ~1400mA (I know I know, if one dies, the other one will be shortly after), but it's apparently still lacking the voltage I quite need. I contacted...

Added the resistors last night and immediately got a bump in power, not as much as I expected though. Powering two diodes in parallel to drain of the same mosfet yields 450mA still, source to a 4.75 regulated power supply (measures 4V under load). If I remove the 1 ohm resistor from series with...

hahaha well... I meant I took off that resistor from pin 2 to 4. ;) Yes, I forgot to draw in the pull down resistor on the fet. That IS there. I'm using a 10k ohm resistor. Ok, so the transistor needs a 10k resistor in series to the base? And just so I understand... that resistor is to limit...

this is for a high powered led driver. The diode will go to the mosfet drain. I attached a schem just now... Now that I've worked out the details of my regulator for the LED, I haven't put in on this circuit yet since it doesn't seem like the fet is open enough to power the LT1185 (with even...

Ok, so I am pretty sure I've nailed down a couple of reasons I was having issues... biggest one is the old and tired batteries I was using. The Power Supply is definitely what I should have been using to prototype this to get the right values. haha What was I thinking? Now, I have a couple of...

Interesting... my batteries have huge internal resistance. Some different batteries did a better job at 580 mA, but their Ri was high ish as well. Power Supply gives 680mA and odd enough, these diodes were running 3.4V for that current. They're rated for 2.6v@700mA Used power supply on a full...

I think you guys have it. .. 1. I remember previously building a driver for an m140, and I completely removed the voltage setting. That seemed to work very well for that. . I'll try that in the morning. 2. I tested the batteries with drlava's method and found out my batteries are in really...

dummy load is just like the oooold popular one here on the forums but it's with .7V 3A diodes and a 1 ohm 5 watt resistor. I measure current two ways. 1, I measure mV across the resistor which makes 1mV = 1mA. 2, with the Multimeter in 'current' mode up to 10A, I connect the driver out pos to...

derp... yes. I drew it wrong. The load neg connects to pin 4 (not the resistor, but to pin 4) my bad. It's driving me up a wall that I get the right load on the dummy, but not the diodes. I know diodes differ between each other, but that much of a difference doesn't make any sense.

Sorry, thought I mentioned... the volt drop of each diode when in series (measured on the anode and cathode of the diode) is about 3V. So when it's in series, there is actually 6V across the 2 diodes which leaves another 1V or so to be burned off by the regulator (although I didn't actually...

Yeah sorry. Here's a diag. I didn't write on there (sorry) but the output current should be 700mA (and it is for one), but is only 450 when two diodes are in series. oh... and the un-valued resistor is 20k. The specs for the LT1185 makes this ~7V , 700mA I know the voltage is 8.4 when freshly...

I have been trying to build a fairly elaborate circuit for the past month or so and kept running into an underpowered problem, so last night I did some actual testing with the bare essential components. Here's what I have: Two 18650 in series (7.4V) LM1185 regulator set to 7V and 700mA Two Red...

Besides those LEDs, I could try switching out different components... the LEDs all came on the same star and are binned the same, so I wouldn't expect the big difference there, but small differences do add up. Thanks for slapping sense back into me! :thanks:

Right you are. I don't know why I was bent on thinking the voltage would be the same when under load. duh. Battery fundamentals... I was previously using a desktop power supply initially... :D Thanks ok - other side of the problem... the 2 constant LEDs in parallel aren't equally sharing load...

Ok... measured voltage and drew a simple diagram. When switch is on: mosfet not connected to 555 timer Vgs: 3.3 Vds: .03 Vds (when off): 3.03 LED Vf: 3.06, Iled: 650mA