how to increase the output current of negative voltage IC

[malik_123]

how to increase the output current of a regulator

i am using lt1044 smd package to convert 7 volt to -7 volts

but out put current is very low

i need 50 mA

is there any way by which i can increase current handling of the ic

 

[BABESH]

how to increase current output

Hi,
Try connecting two lt4011 in parllel, you should able to get some improved performance..


--Babesh.

 

[sau_sol]

how to increase increase current

you can try using pull-up resistances in the output line to drive more current

 

[erohanip]

boost current lm337

Try using ADM660 it is capable of supplying 100mA current

 

[pranam77]

negative voltage ic

Hai Mailk_123,
Try this Adjustable negetive voltage regulator using LM337 (TO 220 package). Remember to keep the input voltage, minimum 3volts above the output voltage required. Adjust the 5K variable resistor to get the desired voltage at the output. This package mentioned can deliver practically up to 1.0 ampheres with good heat sink. For 50 Ma, u may use it as it is. Hope it helps you. Good luck

 

[malik_123]

increase output current in a circuit

i cannot use parallel configuration as ic is costly

second ,

i wonder how can i pull up i am getting the negative voltage from the ic , using POSITIVE voltage

ADM660 solution is good , i have to just check if this IC is availble in local market or not

to use the lm337 ,

i have a question that in the case of using lm337 from where the ic get the input current

from negative Vin ,
am i right ?

but my problem is not to regulate the out put voltage

my problem is to generate the negative out put voltage

from the positve

had i already -12 v i would not have problem
i could have used it as well







i am now trying to use
lt1074
for the negative converter

but i am unable to figure out from its data sheet that how can i control out put voltage ?

it gives the circuit of the -5 voltage but i want to have -7

if i can create -12 v then i can use some other regulator to decrease it to regulated voltage

but i believe some how we can generate the -7 regulated voltage from lt1074

please
see the data sheet and if some one can figure out which parameter control the out put voltage then let me know it

 

[hakeen]

how to increase the current supply

Hi

It is quite difficult task with 50mA@7V, though it is not impossible.

I briefly checked datasheet of 1074, it is boost converter, not negating supply. That is you need already negative supply at Vin to have -7V at output.

As far as I undertsand you can't use also ADM660, as max Vin is defined @7V, and by 50mA load current there is a typical voltage drop more than 0.5V. So, even in typical case (e.g. at room temp) you will not have a healthy -7V output. A similar part is also available by Linear T. and it has less drop than ADM660, but LT part (LTC660) has 5.5V max Vin. At least datasheet is more fairly written.

I found out LT1044A up to 12V negating supply. Maybe it can help to you.
http://cds.linear.com/docs/Datasheet/lt1044a.pdf

Load current of 50mA seems possible.

Cheers

 

[hemant03]

regulate negative voltage

Hi,
Try using LTC1144. It gives around 50mA at 15V. Put a resistor divider network and get - 7V at the output but some current would be lost.
Also you could try putting a X'stor switch to get the desired voltage and current.
Thanks,
- Hemant

 

[JStuffer]

how to increase current

Hi, i don't know how constrained you are by size limitation, but you may use a switching regulator like MC34063 - it's just 8-pin PDIP or SOIC package.
Constructing an inverting regulator with this is quite simple; if you're interested, look here:
**broken link removed**

 

[sush]

how to increse voltage regulator output current

i'm not sure but you can try adding power transistor by taking the idea from the circuit diagram i have attached. Just try reversing the things for Negative voltage.

 

[malik_123]

more current negative voltage

hello sush

i am going to try ur suggestion

i am wondering will it work with the power mosfet as well , i mean if i replace the TIP transistor with the Mosfet , should it work
i think it should .what u say ?

 

[grittinjames]

how to create negative voltage using ic

you can use Lm7906 with a diode between GND pin to GND. It will give you -6.7.
This will be a easy way i think