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steev
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Posts posted by steev
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It's me again!
I nearly have done the powersupply, only the transformer is not available :-\
Although here are the first pictures including a modified layout:
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exactly i too had hard time in finding those 5804 chip.
either no availability or too costly for a small CNC project.so i moved for pic based stepper controller(linistepper) -
I just finished the the layout and the schematic diagramm (Eagle files) !!
After buying all reqired parts I will post some fotos and a link to the german HowTo ;D -
You changed the value of R7 by 8.5%. Then the max current might not be 3A, depending on the actual value of the current-setting pot and other resistors. Some people add a trimpot in series with each pot for calibration of 3A and 30V.
Well, the problem is, that i cannot find exactly the same resistor... I only found 9 Watt resistors from 0,33 to 0,47 Ohm, but it would be too small, wouldn't it?
And don't worry about the cooling stuff, I have some old CPU cooler. I wanted to use a fan anyway ::) -
Once again a big thanks for your help!!
After searching a while on my german shop's site I decided to choose these parts:transformer: RKT 12015
R1: 2W METALL 2,2K
R2: 2W METALL 82
R3: 1W 220
R4: 1/4W 1k
R5, R6, R13, R20, R21: 1/4W 10k
R7: 11W AXIAL 0,51
R8, R11: 1/4W 27k
R9, R19: 1/4W 2,2k
R10: 1/4W 270k
R12, R18: 1/4W 56K
R14: 1/4W 1,2K
R15: 1/4W 100
R16: 1/4W 1K
R17: 1/4W 33
R22: 1W 3,9K
R23, R24: 2 x 2W DRAHT 0,33 (the two resistors for Q4)
RV1: PIHER 10-S 100K
P1, P2: P6M-Lin 10k
C1: AX 10.000/63
C2, C3: RAD 47/63
C4: MKS-4 100N
C5: MKS-4 220N
C6, C9: NPO-2,5 100P
C7: RAD 10/63
C8: NPO-2,5 330P
D1, D2, D3, D4: KBU8B
D5, D6: 1N 4148
D7, D8: ZD 5,6
D9, D10: 1N 4148
D11: 1N 4001
D12: LED (LED 5MM 2MA RT)
Q1, Q2: TIP 31C MBR
Q3: BC557C
Q4: 2 x 2N 3055
U1, U2, U3: OPA 445 AP
and some heatsinks I already bought. Are the 10.000 uF of C1 enough? It's the biggest on I found...
BTW: I would really like to make a HowTo of my version of the power supply aviable on my (and another modding-) website with downloadable schematic diagramm and layout (of course selfdesigned and with the fitting parts). Are I'm allowed to do this or is there any problem because of the copyright? I DO NOT want to sell the power supply or its HowTo! -
Thanks for your reply! I decided to use the KBU 4J. Are there any other parts, which would also work on there limit, if I have a max current output of 3.3 A on the transformer?
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First of all, I want to use this transformer. Yes, I'm from Germany ;)
Input Voltage: 230 V
Output Voltage: 2x 12 VAC
Output Current: 2x 3,33 A
Power: 80 VA
Do you have any partnumber for suitable diodes? I don't really want the 1N5402 to operate on there limit, I would realy like some buffer up to 4 A?! -
I ust worry about D1, D2, D3 and D4 because they are specified for only 3.0 A but there will be an possible input current of 3.3 A ???
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Just a short question: What do I have to change, if i want use an 24 VAC 3,3 A transformer for the "0-30 VDC STABILIZED POWER SUPPLY" and the "Voltmeter + Ammeter LCD panel"?
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Hi AudioGuru
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well that pic u posted look like FM transmitter?
but u said u want RF transmittr right...aim i confused :-\ -
"5"
?? ??? ??? -
well why i liked above ckt is bcz of its simplicity.
it can remember the last distance travelled.
and ofcourse i need speed of the bike.i may face problem while attaching the sensor moudule on wheel. -
then insted of using char. display LCD u shld go for graphic display LCD
so ru gona make this ckt?or do u have any other speedometer schematic. -
well iam also thinking of making such thing
i found this http://www.edn.com/article/ca529384.html
but i need help in microcontroller handling and programming -
well i did this long time ago.
drawback in IR is u have to maintain direction.
try to get a cheap RC car(china made) remove motor from receiver and connect LED's in series or parallel according to ur LED count throght some resistor(to protect the LED)
if the LED count is high,connect the output to relay from which u can power a lot led's -
i found 2 ckts for this purpose
http://www.geocities.com/tjacodesign/supply/supply.html
http://www.electronics-lab.com/projects/power/022/
which one u think efficient and safe for driving an led -
ohh right.then i miscalculated the resistor value.
problem here is i dono the forward voltage of the led iam using.
i got them from a local electronics shop(shop guy said that he dono LED details).they r bright enough when i connect 2 AA cells in series.
so can i consider its forward voltage as 1.8v.or there any specific method to measure the LED forward voltage -
OOps i forgot.
we r using 5 100Ohms resistors for each(5) LED seperately.to provide exact amount of current.but the problem is with the output supply of receiver circuit.its only working when we feed 3.6volts exactly.and when we connect led to this voltage they r burning out.(i fried up 10 led till now) :'(
i know using lm317 we can get exactly 3volts(thanks to audio guru and ante).but problme is with heat.
in other thread someone said that we can drop voltage by 0.6v using a diode.can i keep voltage exactly 3v from this diode method.or is there any seperate ckt for this (i need circuit as small as possible with no heat generation.) -
hi again
we can't use more voltage here as the receiver is rated at 3.6v only.so we decided to go with parallel connection(we found a good high current battery pack).so can u show me a circuit which can flash 5(we decreased the number) LED's with appx. 0.5sec timing gap.
and one more thing is size of circuit.we almost ran out of space.so pls show us some small circuit.
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can we glow a 3v led(@20-30ma) using above schematic.
iam also looking for such circuit.it is for powering a single led.i can't use transformer as there is no enough space.
i tried in groups(google) most of them look dangerous to me.
is there any safe design -
u said some thing abt flasher.
will it saves current.while searching for a max600 based flasher i found this
http://www.laserfaq.org/sam/samschem.htm#schmsc5b
what do u say abt it.
and pls post ur flasher schematic too.
thanks -
i got some max 660 chips (http://www.maxim-ic.com/quick_view2.cfm/qv_pk/1140)
so can we use this chip to make the circuit work for long times.
like http://www.mitedu.freeserve.co.uk/Circuits/Misc/ledtorch.htm -
series means more voltage.thats why we choosed parallel connection.
so is it possible to boost current?
Power Supply and Multimeter at 3,3 Ampere...
in Power Electronics
Posted
The powersupply itselves is done so far. I can change the voltage from something about 0 up to 30 Volt and the current LED seems to work fine!
Now I have to grill some AVRs to get the multimeter working ;D and build a small case...
Want to see some pictures? Here you go: