Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

LM7806 for 6V DC motor?

Status
Not open for further replies.
M

maniac84

Full Member level 6
Full Member level 6
Joined
Mar 4, 2012
Messages
337
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,298
Activity points
3,661
May I know can the LM7806 be able to power up a 6V DC motor?
Does it have enough current to turn the motor on? I don't have the motor datasheet. I'm asking generally.
 

It should work for a small motor, but not for a big one.
 

LM78XX series regulator comes with 1 A output current capacity. its depends on your motor voltage supply requirement if your dc motor is turn on at 6v then it will go on but i suggest to have datasheet of your motor so you can know requirement to on your DC motor.
 

ud23 said:
LM78XX series regulator comes with 1 A output current capacity. its depends on your motor voltage supply requirement if your dc motor is turn on at 6v then it will go on but i suggest to have datasheet of your motor so you can know requirement to on your DC motor.
Click to expand...

I've attach the spec for the 6V motor:View attachment 2619_SR_MME.pdf
The part number is 2619S006SR207:1 which is a 6V DC motor. Can the LM7806 drive this motor?
 

Yes. Power is about 1W, so current is less than 1A.
 

If this LM7806 is also use to power a pic18f26k20 mcu? Will it be enough?
 

How much current does the mcu use?
 

godfreyl said:
How much current does the mcu use?
Click to expand...
I'm not sure. There's too much current value in the datasheet. **broken link removed**
Not sure which one is the value you need. Could you help me see?

---------- Post added at 00:48 ---------- Previous post was at 00:44 ----------
tpetar said:
78s06 2a
78t06 3a
Click to expand...
??
You mean there's 78s06 which can produce 2A current and 78t06 which can produce 3A current? But I could not find any info about them in the internet.

---------- Post added at 00:58 ---------- Previous post was at 00:48 ----------

By the way, what is ration 207:1 means for my motor?
 

Yes

7806 is 1A
78S06 is 2A
78T06 is 3A

Also you can use :

LM350 to make 6V 3A, or
LM338T (TO220) LM338K (TO3) 5A to make 6V 5A, or
LT1083CP (TO3) to make 6V 7,5A.

---------- Post added at 19:23 ---------- Previous post was at 19:09 ----------
By the way, what is ration 207:1 means for my motor?
Click to expand...

If you see table in motor datasheet its obvious what is this. Just compare motors data. See speed column.
 
maniac84 said:
I'm not sure. There's too much current value in the datasheet. **broken link removed**
Not sure which one is the value you need. Could you help me see?
Click to expand...
Page 1 of the datasheet says "Operating Voltage Range: 1.8V to 3.6V", so you can't use that mcu with a 6V supply.

By the way, what is ration 207:1 means for my motor?
Click to expand...
There is a gearbox attached to your motor. "207:1" is the gearbox ratio.
 
Actually I hv another regulator lm1117-3.3 to step down 6v to 3.3v. So my mcu wil get a 3.3v. So wif all this other compenents, I'm asking is the current generated from lm7806 enough to operate my motor?
 
Last edited:

Yes, uC supply voltage is in range 1.8V to 3.6V (max 4,5V), use 6V regulation for motor and 3,3V for uC and no problem.

uC consume from several uA up to few mA.

• Sleep mode: < 100 nA @ 1.8V
• Watchdog Timer: < 800 nA @ 1.8V
• Timer1 Oscillator: < 800 nA @ 32 kHz and 1.8V

---------- Post added at 03:47 ---------- Previous post was at 03:40 ----------

For voltage regulation to 3,3V you can use :

LF33CV 1A TO220AB
78L33 100mA TO92 (its enough for uC dont worry)
LM3940IMP-3.3 1A SOT223 TO220AB
LM1085IT-3.3 3A

---------- Post added at 03:50 ---------- Previous post was at 03:47 ----------

Use small heatsink for 7806 or 78S06.
 

tpetar said:
Yes, uC supply voltage is in range 1.8V to 3.6V (max 4,5V), use 6V regulation for motor and 3,3V for uC and no problem.

uC consume from several uA up to few mA.

• Sleep mode: < 100 nA @ 1.8V
• Watchdog Timer: < 800 nA @ 1.8V
• Timer1 Oscillator: < 800 nA @ 32 kHz and 1.8V

---------- Post added at 03:47 ---------- Previous post was at 03:40 ----------

For voltage regulation to 3,3V you can use :

LF33CV 1A TO220AB
78L33 100mA TO92 (its enough for uC dont worry)
LM3940IMP-3.3 1A SOT223 TO220AB
LM1085IT-3.3 3A

---------- Post added at 03:50 ---------- Previous post was at 03:47 ----------

Use small heatsink for 7806 or 78S06.
Click to expand...

Thanks for the info.
Now I'm scared of the 6V dc motor can't work. I'm not sure how much current it needed. Do you guys have any idea?

---------- Post added at 13:21 ---------- Previous post was at 13:18 ----------
tpetar said:
Yes, uC supply voltage is in range 1.8V to 3.6V (max 4,5V), use 6V regulation for motor and 3,3V for uC and no problem.

uC consume from several uA up to few mA.

• Sleep mode: < 100 nA @ 1.8V
• Watchdog Timer: < 800 nA @ 1.8V
• Timer1 Oscillator: < 800 nA @ 32 kHz and 1.8V

---------- Post added at 03:47 ---------- Previous post was at 03:40 ----------

For voltage regulation to 3,3V you can use :

LF33CV 1A TO220AB
78L33 100mA TO92 (its enough for uC dont worry)
LM3940IMP-3.3 1A SOT223 TO220AB
LM1085IT-3.3 3A

---------- Post added at 03:50 ---------- Previous post was at 03:47 ----------

Use small heatsink for 7806 or 78S06.
Click to expand...

Thanks for the info.
Now I'm scared of the 6V dc motor can't work. I'm not sure how much current it needed. Do you guys have any idea?
 

Now I'm scared of the 6V dc motor can't work. I'm not sure how much current it needed.
Click to expand...

Why you think that ?

1A regulator should be fine, but I suggest usage of stronger 2A or 3A with small heatsink of course.

You can use multimeter as DC current meter, set to 10A range an put into circuit with motor and battery or some power supply of 6V voltage, and you will see current.

I think this motor will consume about 0,5A-0,7A max.
 
Last edited:

of COURSE the 7806 will work. Why is there any doubt ?

Your DC motor will work with any voltage from near zero upto and beyond 6v. It is rated for 6v as a max only, at the rated rpm. At lower voltages the rpm will be proportionately lower - thats all.

The 7806 is capable of delivering (6 x 1) = 6 watts (with proper heat sink), which is more than enough for your 1w motor.

Next - what you need to worry about is power dissipation in your 7806. What is the input voltage your are feeding ? Yuo should keep this voltage as low, but higher than, the 7806 differential. Usually around 2 volts. This will ensure that power is minimal in the 7806. If the input voltage is higher than 8v, then a small series resistor of appropriate wattage can be used, or even power diodes (1N4001 type) in series.

cheers & all da best !!
 
I've added in a 5K trimmer because I plan to adjust the motor speed by controlling the the voltage. But seems like the motor only will turn on at 6V and around 150mA and my trimmer is already set at 0 ohm. If I increase the resistance of the trimmer higher a bit, the motor will stop. Is it that my current is not enough?
I mean, can I design in such a way that I use a trimmer to adjust the voltage to the motor n as a result adjusting the motor speed?
 

Oh good ***. Did you put the trimmer in after the 7806 ?!? And that too a 5K one ?

Maybe you should stay away from electronics my friend.

cheers!
:D
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top