Schema: 12volt to 9volt voltage regulator

[Thor]

I currently have solar panels charging batteries via a charge controller and then I have one of my routers connected to the load of the charge controller since both the charge controller and the Mikrotik is 12volt.

However my VDSL modem (Netgear) is 9volt.

I want to build a 12volt to 9volt DC to DC inverter.

Any idea what parts I need (Yebo electronics is down the street.) and I'm comfortable soldering, just need a schema.

 

[thehuman]

Maybe, would need to set voltage with multimeter
https://www.fort777.co.za/index.php?main_page=product_info&products_id=18233

 

[Brandon]

Get a 7809 voltage regulator, depending on the model should handle up to 35vdc in and give 9vdc 1A out. Cost around R7 each. You can connect them in parallel to achieve a higher amperage handling. Also get a small heat sink.

 

[Thor]

Maybe, would need to set voltage with multimeter
https://www.fort777.co.za/index.php?main_page=product_info&products_id=18233

Meh, there we go that is exactly what I was looking to build. For R134.71 I think it's worth the money a soldering iron will probably cost me more than that.

 

[Thor]

Get a 7809 voltage regulator, depending on the model should handle up to 35vdc in and give 9vdc 1A out. Cost around R7 each. You can connect them in parallel to achieve a higher amperage handling. Also get a small heat sin

That is neat, I think I will buy the stuff to build this one as well, I like the DIY approach.

 

[Brandon]

That is neat, I think I will buy the stuff to build this one as well, I like the DIY approach.

They're quite old tech, but get the job done and are commonly available. Just remember to use a heat sink as they generate a bit of heat under load, an old CPU heat sink without the fan works great.

 

[Thor]

This also looks viable: http://powersupply33.com/simple-12-volt-to-9-volt-dc-dc-converter.html



Parts List :
R1 = 560 ohm
C1 = 1000µF/16V ( Electrolytic Capacitor )
C2 = 100µF/16 ( Electrolytic Capacitor )
C3 = 330nF ( Ceramic Capacitor )
Z1 = 9.1V, 0.4 watt ( zener diode )
Q1 = ECG184, NTE184

 

[Brandon]

This also looks viable: http://powersupply33.com/simple-12-volt-to-9-volt-dc-dc-converter.html

Will also work, price on the NTE184 is over R40.

 

[Thor]

Will also work, price on the NTE184 is over R40.

Stock availability in SA

Do you guys have a schema for me on how to use this transistor?

 

[Thor]

What is the advantage of the circuit I was looking at earlier vs this approach?

 

[Düber]

What is the advantage of the circuit I was looking at earlier vs this approach?

I would hazard a guess that your circuit and perhaps more is built into the TSR.

 

[RedViking]

Why don't you just buy a buck boost converter of one the Chinese sites.
They are like R35

ZAR 32.70 | DC CC 9A 300W 150W Boost Converter Step Down Buck Converter 5-40V To 1.2-35V Power module
https://s.click.aliexpress.com/e/cHD7qKCo

Yes it will arrive when the DA took over.

 

[Brandon]

What is the advantage of the circuit I was looking at earlier vs this approach?

The TSR is way more energy efficient and uses frequency switching to step down the output - but is a more expensive component. The 7809 and xx184 circuit are both linear regulators, they are cheaper, but generate heat due to inefficient conversion.

There are quite a few other makes of DC/DC step down converters like the TSR out there, you would need to confirm what your local electronics shop stocks.

Why don't you just buy a buck boost converter of one the Chinese sites.
They are like R35

ZAR 32.70 | DC CC 9A 300W 150W Boost Converter Step Down Buck Converter 5-40V To 1.2-35V Power module
https://s.click.aliexpress.com/e/cHD7qKCo

That is cheap for 9amps output, but probably an overkill for the intended load. I would also be cautious with cheap Chinese power products (think MTBF due to cheap components).

 

[Jake45]

Have you tried to power the VDSL router from a 5V power bank? An Adata 5000mAh power bank costs R130 on Loot and a 10000 about R190.
https://mybroadband.co.za/forum/threads/router-battery-backup.993476/page-15#post-23143044

Alternatively you could just purchase 4X 3A silicon diodes and put them in series in the power lead. Each diode should have a forward voltage drop of around 0.7~0.8V i.e. 4 in a row will drop the voltage by 4X 0.8 = 3.2V. 1N5401 diodes should be suitable and cost around R1.00 each.
http://www.mantech.co.za/Stock.aspx?Query=1N5401and

 

[thehuman]

Have you tried to power the VDSL router from a 5V power bank? An Adata 5000mAh power bank costs R130 on Loot and a 10000 about R190.
https://mybroadband.co.za/forum/threads/router-battery-backup.993476/page-15#post-23143044

Alternatively you could just purchase 4X 3A silicon diodes and put them in series in the power lead. Each diode should have a forward voltage drop of around 0.7~0.8V i.e. 4 in a row will drop the voltage by 4X 0.8 = 3.2V. 1N5401 diodes should be suitable and cost around R1.00 each.
http://www.mantech.co.za/Stock.aspx?Query=1N5401and

A leas acid battery can swing between 14v and 10v , with doided output will follow that swing less volt drop

 

[Thor]

Why don't you just buy a buck boost converter of one the Chinese sites.
They are like R35

ZAR 32.70 | DC CC 9A 300W 150W Boost Converter Step Down Buck Converter 5-40V To 1.2-35V Power module
https://s.click.aliexpress.com/e/cHD7qKCo

1 I don't trust any of their electronics and two it will never arrive here.

 

[Thor]

I wonder if Yebo will have a TSR?
If not where in Bellville can I get it?

 

[Thor]

That helps, where did you order from?

I am going to buy this now https://www.netram.co.za/1806-dc-dc-step-down-power-module-125v-35v.html

 

[Thor]

Went to Netram best damn service there is! Replies within 2 minute on E-mails and incredibly cheap especially Raspberry Pi and Arduino, I mean they where product for product 40 to 70% cheaper than Yebo Electronics.