terahz
1x10^12 Hz
Correct. The latest version will always be there. It happens to be v0.7. I've just stopped naming the files since git is a revision control system.
DIY LED driver for reef lighting
- Thread starter der_wille_zur_macht
- Start date
Correct. The latest version will always be there. It happens to be v0.7. I've just stopped naming the files since git is a revision control system.
Thats what i thought. I intend to have each of the strings (listed in previous posts) on a separate driver. The bit Im not clear on is if each of the drivers need to see the same Vin / Current. Iv done a bit of research on the subject and not really found anything saying either way.
Check this out- kinda looks familiar to me? I hope they didn't use the EAGLE freeware to produce this! http://saltydogaquariums.webs.com/apps/webstore/products/show/3060277
shirley386
Member
terahz - What's the chance of you posting the gerbers for your LM3409 I2C V0.6 board?
Thanks
Shirley
Thanks
Shirley
Euler Kernighan
The "DIY Guy"
bump on this ^^^
Hi guys
Im building cat4101 drivers and don't know much about electronics. I also made a 555 pwm dimmer, tried to test this output from the transistor with a multimeter, got 4.8volts max and 0.66v min does this sound right? Was just wondering if pwm had to be 5v to run cat4101 at 100% Or is this not an accurate way to test the dimmer.
Im building cat4101 drivers and don't know much about electronics. I also made a 555 pwm dimmer, tried to test this output from the transistor with a multimeter, got 4.8volts max and 0.66v min does this sound right? Was just wondering if pwm had to be 5v to run cat4101 at 100% Or is this not an accurate way to test the dimmer.
theatrus
100-mile-commuter
That should be ok for a logic signal. Note that time-variant signals are not a multimeters best friend, so expect error in your measurements (in fact I'm impressed you have a min/max capability). What frequency?
Don't think it does have that, what I meant to say was with the pot turned to max end 4.8v & .66 at other end. So this is just showing the pwm as an average in volts? Dont know what im doing but I googled and read somewhere, thats what its displaying. Could I wire a switch in the pwm wire to the cat4101 and switch from the 555 signal to full psu 5.3v . I could just check difference in brightness by eye
Wanted to build the driver using the NCP3066 chip. Was wondering what values should I choose for the inductor and current sense resistor if I need to get the 1Amp output.
The BOM shows the inductor value as 100uH 1A for 500mA output. To get the 1A o/p what is the value of inductor should I choose and the resistance value for R4 & R11? I was not able to find the current sense resistor values to be chosen for each current o/p in the datasheet of the chip.
The BOM shows the inductor value as 100uH 1A for 500mA output. To get the 1A o/p what is the value of inductor should I choose and the resistance value for R4 & R11? I was not able to find the current sense resistor values to be chosen for each current o/p in the datasheet of the chip.
theatrus
100-mile-commuter
Then it's just showing an average voltage (of some kind). It appears your 555 is operating just fine.
theatrus
100-mile-commuter
The inductor Henry's stays the same (looks like 47uH in buck), but you need to pick a part with a higher current and saturation current rating. I haven't looked at the specifics here. OnSemi has an online design tool.
The Rs resistor sets the limit when there is 200mv across it. Using ohms law that gives 133milliohms for 1.5amps. Note there is .3w in this resistor so pick a larger size package.
The 1A value is 200milliohms.
Last edited:
DWMZ,
Please help me with a BOM for below
I plan to build mine as follows with XMLs,
48V in
46V out
2A out
14 LED per IC
Will BOMs differ if I want to use PWM/Analog?...and hope not layout?
BTW I hope I can still use the same schematic? but the .brd file? I suppose its package is different for QHV.
I have checked your XL
http://hpled.googlecode.com/svn/trunk/lm3409/lm3409_component_worksheet.xls
is it built only for LM3409 or for QHV varient as well? I ask so because it has an error when I try to input 48V input and 46V output.
Many thanks for your help, feel free to correct my understaning.
Kumar.
But I have read in an earlier post that the inductor value should be higher than 100uH if the o/p current is more than 700mA.
I download the schematic files and the bom from the below URL.
http://code.google.com/p/hpled/downloads/list
Could anyone please provide me the exact component values for 1A and 700mA output current. The bom provided is for 500mA.
In the mean time, I would try using the online design tool from ON semiconductor.
theatrus
100-mile-commuter
It's a function of switching speed (set by capacitor) and ripple current. See page 9 of the data sheet - you'll see inductance is a function of voltage in and out coupled with switch speed coupled with ripple current.
As for ripple current, this may help (from the datasheet)
DIL − Desired peak−to−peak inductor ripple current. For maximum output current it is suggested that DIL be chosen to be
less than 10% of the average inductor current IL(avg). This will help prevent Ipk (Switch) from reaching the current limit threshold set by RSC. If the design goal is to use a minimum inductance value, let DIL = 2(IL(avg)). This will proportionally reduce converter output current capability.
As for ripple current, this may help (from the datasheet)
DIL − Desired peak−to−peak inductor ripple current. For maximum output current it is suggested that DIL be chosen to be
less than 10% of the average inductor current IL(avg). This will help prevent Ipk (Switch) from reaching the current limit threshold set by RSC. If the design goal is to use a minimum inductance value, let DIL = 2(IL(avg)). This will proportionally reduce converter output current capability.
Help with BOM please
Help with BOM please
Bump for DWZM
(sorry, got the name wrong in last post)
Help with BOM please
Bump for DWZM
(sorry, got the name wrong in last post)
Hi Guys
First I would just like to thank the main protagonists for this great thread...
Second...the question....
I have seen the idea of running the cat4101's in parallel mentioned many times on here, mainly by Fishman
I have a basic understanding of electronics but designing this scenario in eagle is a bit beyond my skill set. So...I was hoping that someone could post up a sch/brd design for running 2 cats in parallel.
My Idea is...
To have one board with 6/7 drivers mounted on it but with 2 drivers running in parallel to run higher than 1a so if needed i can drive the xpg's/xml's that bit higher, future proofing if you like
Cheers
John
First I would just like to thank the main protagonists for this great thread...
Second...the question....
I have seen the idea of running the cat4101's in parallel mentioned many times on here, mainly by Fishman
I have a basic understanding of electronics but designing this scenario in eagle is a bit beyond my skill set. So...I was hoping that someone could post up a sch/brd design for running 2 cats in parallel.My Idea is...
To have one board with 6/7 drivers mounted on it but with 2 drivers running in parallel to run higher than 1a so if needed i can drive the xpg's/xml's that bit higher, future proofing if you like
Cheers
John
Hi Guys
First I would just like to thank the main protagonists for this great thread...
Second...the question....
I have seen the idea of running the cat4101's in parallel mentioned many times on here, mainly by Fishman
My Idea is...
To have one board with 6/7 drivers mounted on it but with 2 drivers running in parallel to run higher than 1a so if needed i can drive the xpg's/xml's that bit higher, future proofing if you like
Cheers
John
DEVS
Here's a dual CAT driver that will work. As it is, both channels are independent of each other. If you want to Parallel the channels, just connect the negative side of your LED string to both negative terminals on the board. I included pots with both chips for current adjustment. All you'd have to do is balance the load between the two CAT chips by adjusting each one to drive half your target current. For example- Say you want to drive a string of six XPG's to 1400 ma. Connect the string to one channel only, power-up, and adjust the current to 700ma. Now connect to the other channel only, power up, and adjust it for 700ma output. finally connect both channels and check the current, It should now be around your target of 1400ma.This design is nice because you're not forced to parallel drive if you don't need to, plus it has a 5V reg included for powering up the driver for situations where there is not a controller providing the 5V turn on signal or dimming signal. Feel free to mod it any way you like.
Finally decided to build the driver using LM3409. Since I got the BOM for 24V & 1A, and 48V & 1A, planning to build using LM.
I see that the IC is not a linear IC like CAT4101. My question is that is it mandatory to use a SMPS or can I use a normal 24V adapter to drive the led's?
Also I wanted to use analog dimming. Is there any tested circuit for LM IC? Could anybody share me a circuit for analog dimming which I could use along with LM3409 IC.
I see that the IC is not a linear IC like CAT4101. My question is that is it mandatory to use a SMPS or can I use a normal 24V adapter to drive the led's?
Also I wanted to use analog dimming. Is there any tested circuit for LM IC? Could anybody share me a circuit for analog dimming which I could use along with LM3409 IC.
1. Analog dim by directly driving the IADJ pin with a voltage source from 0V
to 1.24V
2. Analog dim by placing a potentiometer between IADJ pin and Gnd.
Am following the circuit design posted by der_wille_zur_macht. How do I decide on what value of pot should be used to do the pwm?
to 1.24V
2. Analog dim by placing a potentiometer between IADJ pin and Gnd.
Am following the circuit design posted by der_wille_zur_macht. How do I decide on what value of pot should be used to do the pwm?
