Power Supply Info

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-I dont know why but linksys looks like thay like Starving ther Wireless Routers and Ap's of POWER.+I don't know why but linksys looks like they like starving their Wireless Routers and AP's of POWER.
-thay supply you with a 1 to 1.5 amp "Wallwart" Powersupply way under what you need .+They supply you with a .5 to 1.5 amp switching power supply way under what you need .
-just look a the Product spec sheet lets say just for a wpc300n PCMCIA WiFi card.+Look a the product spec sheet for a WPC300N PCMCIA WiFi card;
-JUST the Card.+ 
Power Consumption Power Consumption
TX: <900mA (Maximum) TX: <900mA (Maximum)
RX: <700mA (Maximum) RX: <700mA (Maximum)
-http://downloads.linksysbycisco.com/downloads/WPC300N_ds,0.pdf 
 +[http://downloads.linksysbycisco.com/downloads/WPC300N_ds,0.pdf http://downloads.linksysbycisco.com/downloads/WPC300N_ds,0.pdf] [broken]
 +
 +
 +Look at what the BCM4705 CPU Power Consumption is;
 +5v @ 2.4w = 0.48 amp just under 1/2 amp.
 +
 +[http://www.broadcom.com/collateral/pb/4705-PB01-R.pdf http://www.broadcom.com/collateral/pb/4705-PB01-R.pdf] [broken]
-Now we need to look at what the BCM4705 CPU Power Consumption is 5v @ 2.4w = 0.48 amp just under 1/2 amp.+the switch BCM 5325 Power Consumption is 5v 1.4W = 0.28 amp
-http://www.broadcom.com/collateral/pb/4705-PB01-R.pdf+
 +[http://www.broadcom.com/collateral/pb/5325-PB05-R.pdf http://www.broadcom.com/collateral/pb/5325-PB05-R.pdf]
-The Switch BCM 5325 Power Consumption is 5v 1.4W = 0.27999999999999997 amp+also add the RAM power consumption (unknown at this time)
-http://www.broadcom.com/collateral/pb/5325-PB05-R.pdf +
-and the Ram Power Consumption is well im not shure what the ram power Consumption is .+Remember the variation that is needed; normally 5% to 10%
-Plus Remember the +/- % that is NEEDED Normaly 5% to 10%+Power needed just for this item at minimum so far:
-And you shuld have a power supply that has a power rating of At least 5% Over what you need to keep things cool.+900 ma
 +270 ma
 +480 ma
 +total: 1650 ma which equals 1.65 amp
-So this is the power needed just for this item at Minimum !! sofar+Other Routers have this problem too!!
-900ma+This is a thread were you can find out More Info if you need: [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=54242&postdays=0&postorder=asc&start=0 DD-Wrt Forum]
-0.27999999999999997 Amp+----
 +Engineer's comment:<br />
 +I'm not refuting the fact that they could very well be power starved, I just want to clear up a misconception of the original author.
-0.48 amp+What is important here is the sum of the POWERS not the sum of the currents.
 +Switching power supplies, are very efficient at converting voltage/current levels; and if properly designed can reach efficiencies of 95%.<br />
-if you Notice your signal looks like a Electrocardiogram readout on a Failing Heart..+Using the values provided above, and assuming a Vbus of 3.3v:<br />
 +1.65a * 3.3v = 5.45w
-Try a 5 Amp Power supply !+The router needs at least 5.45w to operate correctly.
-!!!!!!STAY WITH THE SAME VOLTAGE!!!!!!!+Now let's look at the wall wort.<br />
 +12v output, at 500ma = 6watts.<br />
 +factoring in the inefficiencies of the power supply on the router, it is obvious that we are running at the limit of the wall wort.
-Other Routers have this problem To!! +Recommendation: if you have a 12v/500ma adapter with your router, seriously consider getting a new one.
 +Get an adapter rated for at least 1a at 12v and you should be fine.
-This is a thread were you can find out More Info if you need .+--[[User:Dejagerd|Dejagerd]] 03:26, 19 February 2010 (CET)
-http://www.dd-wrt.com/phpBB2/viewtopic.php?t=54242&postdays=0&postorder=asc&start=0+[[Category:Linksys]]
 +[[Category:Hardware]]

Current revision

I don't know why but linksys looks like they like starving their Wireless Routers and AP's of POWER. They supply you with a .5 to 1.5 amp switching power supply way under what you need . Look a the product spec sheet for a WPC300N PCMCIA WiFi card;

Power Consumption TX: <900mA (Maximum) RX: <700mA (Maximum)

http://downloads.linksysbycisco.com/downloads/WPC300N_ds,0.pdf [broken]


Look at what the BCM4705 CPU Power Consumption is; 5v @ 2.4w = 0.48 amp just under 1/2 amp.

http://www.broadcom.com/collateral/pb/4705-PB01-R.pdf [broken]

the switch BCM 5325 Power Consumption is 5v 1.4W = 0.28 amp

http://www.broadcom.com/collateral/pb/5325-PB05-R.pdf

also add the RAM power consumption (unknown at this time)

Remember the variation that is needed; normally 5% to 10%

Power needed just for this item at minimum so far: 900 ma 270 ma 480 ma total: 1650 ma which equals 1.65 amp

Other Routers have this problem too!!

This is a thread were you can find out More Info if you need: DD-Wrt Forum


Engineer's comment:
I'm not refuting the fact that they could very well be power starved, I just want to clear up a misconception of the original author.

What is important here is the sum of the POWERS not the sum of the currents. Switching power supplies, are very efficient at converting voltage/current levels; and if properly designed can reach efficiencies of 95%.

Using the values provided above, and assuming a Vbus of 3.3v:
1.65a * 3.3v = 5.45w

The router needs at least 5.45w to operate correctly.

Now let's look at the wall wort.
12v output, at 500ma = 6watts.
factoring in the inefficiencies of the power supply on the router, it is obvious that we are running at the limit of the wall wort.

Recommendation: if you have a 12v/500ma adapter with your router, seriously consider getting a new one. Get an adapter rated for at least 1a at 12v and you should be fine.

--Dejagerd 03:26, 19 February 2010 (CET)