# Stepping up 2.4V into 3.4V

Discussion in 'The Projects Forum' started by frustratednoob, Dec 21, 2012.

1. ### frustratednoob Thread Starter New Member

Dec 21, 2012
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0
Hey guys, this will be my first time posting in this forum.
I was just wondering how do you step-up/boost a circuit from 2.4V to 3.4V using a boost converter?
I was searching for that schematic online, but I have found many designs that are somewhat different.

*I'm using 2 x 1.2V AA NiMH Rechargeable Batteries, with a total current of 4600mAh, or 2300mAh each.

2. ### t06afre AAC Fanatic!

May 11, 2009
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How much current do you need? That is also important to know in order to help you

3. ### Audioguru New Member

Dec 20, 2007
9,411
896
No.
With two cells in series you get 2.4V at 2300mAh.
2300mAh is not the total current, it is the time duration of a certain current which might be 2.3A for 1 hour. The total current might be 12A for a few minutes.

4. ### ScottWang Moderator

Aug 23, 2012
4,925
777
If you use 1.2V x 3 then you will get 3.6V/2.3A.
If you use boost converter may like this:
W_in = 2.4V x 2.3A = 5.52W
Assuming transfer effiency is 80%
Iout = 5.52W/3.4V = 1.623A
If you use pwm then the output current could be Iout_pwm = 1.623A / 2 = 0.812A

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