# 2.4V to 5V Step Up DC-DC Converter

• Rajkumar Sharma
• 47845
Views
• medium
• Tested

This project is a step up DC to DC power converter able to convert 2.4V – 5V to 5Vdc.

### Description

This project has been designed around Texas Instruments LM2623 IC, The LM2623 is a high efficiency, general purpose step-up DC-DC switching regulator for battery powered and low input voltage systems. It accepts an input voltage between 2.4V to 12V volts and converts it into 5V DC. Efficiencies up to 90% are achievable with the LM2623.

### Features:

• Good Efficiency over a very wide load range
• Very low output voltage ripple
• 2.4V to 5V (Possible Input Supply up to 14V operating voltage)
• 5V output voltage (Other output voltages possible by changing R3 and R4)
• 600mA output current

### Application:

• Hand held instruments
• Cameras, PDA, Cellphones
• White LED driver

### PCB

• Nizam uddin

I like electronics lab.com

4 years ago
• Electronics Lab

Thanks for visiting!

4 years ago
• hakanak

Does it provide 5V continously even when the input is 2.5V ?

3 years ago
• Electronics Lab

Sure, input can be in the range of 2.4 – 12V

3 years ago
• AlexRogers

will the output be stable if the Vin fluctuates?

2 years ago

That’s the purpose of this voltage converter. Keep in mind that the voltage should be inside the input limits.

2 years ago
• Sorry, i am really zero knowledge of this, and i dont know where to start learning. can i ask how much R3 and R4 should be for output around 3.3v-3.5v. thanx if you want share how to calculate it. 🙂

3 years ago
• Electronics Lab

I can’t enter the equation here. Please check on datasheet page 11 – chapter 8.2.2.3 Setting the Output Voltage. http://www.ti.com.cn/cn/lit/ds/symlink/lm2623.pdf A value of 50k to 100k is suggested for R4. Then, R3 can be selected using Equation 1.

3 years ago
• yes, i see.. thanx for the link and reference page number..:) so if R4 is 100k, i just need R3 150-160K.. really thanks…

3 years ago
• kim

What kind of inductor you used here and what is R2 0E?

2 years ago
2 years ago

R2 it’s a zero Ohm resistor

2 years ago
• kim

Can i use this inductor? https://www.amazon.com/uxcell-Axial-4-7uH-Color-Inductors/dp/B008MP0HS0. Can i ask the C5 too? Can i use a through hole capacitor? Thanks

2 years ago

No, you will need a high power inductor like the one on the mouser.com link above. As for C5 you can use a through hole capacitor that will be fitted on the PCB.

2 years ago
• kim

Can you recommend an alternative inductor that is not surface mounted because i need it for my project and we need to put it on breadboard. Thank you so much 🙂

2 years ago
• kim
2 years ago

It should work.

2 years ago
• kim

can i use electrolytic capacitor on C5?

2 years ago
• kim

How about using a 1.5V or 6V battery for the input?

2 years ago
• kim

can i use a polarize capacitor for C5?

2 years ago

It’s better to use a ceramic capacitor there.

2 years ago
• kim

Can i use solar panel that’s 3V for the input instead of a battery?

2 years ago

You may use a solar panel on the input that is able to provide 2.4 to 12V output.

2 years ago
• kim

Hi! When i finished breadboarding the circuit and put an input voltage of 6 volts the output was 6 volts too. Why does it happened? 🙁

2 years ago

Please try a lower input voltage at the range of 2.4-4.5V to check if the regulator converts it to 5V

2 years ago
• kim

Hi 🙂 I changed the input into 3V but the output is 3V too.

2 years ago
• mixos

Please check for damaged diode or IC.

2 years ago
• what is the output A’s

2 years ago

max output current is 600mA

2 years ago
• Eddy

What are the exact dimensions of the pcb drawn in this page. Thanks.

2 years ago

PCB dimensions are 24.13 x 26.99mm

2 years ago
• Eddy

Can i use through hole components (on a new pcb) for all the parts (except the lm2623 of course) ?

2 years ago

Sure, it will work just fine.

2 years ago
• Eddy

Another issue : is there a way to improve the maximum output current to let’s say 1.5A or 2A. What are the modifications needed for this purpose? Thanks in advance.

2 years ago

For that output current, you probably need a completely new design with different IC.

2 years ago
• PCB Size 24.13X26.99MM

2 years ago
• Eddy

Thanks

2 years ago
• Eddy

Why the output is oscillating continuously between 4.8 and 5.3 V (not stable) ?

2 years ago

Have you placed all filtering capacitors to the output?

2 years ago
• Eddy

Have rebuilt the circuit using your pcb (not the mine) and it works just fine. I’m using it to feed an audio amplifier rated at 6w (2x3w) so the current drawn is 1.2A (6w/5v) vs an announced nominal current of 500mA ?? Is there an explanantion.
Thanks.

1 year ago

6W should be the maximum instantaneous power delivered to the speakers and not RMS power which is lower. So that’s why your amplifier has 500mA nominal current.

1 year ago
• James

where can I buy the components for this board?

1 year ago

Your can source the parts online from various suppliers, like mouser.com ebay.com and others.

1 year ago
• Anil Tan

Hi i need to charge my samsung s8 with this kind of circuit via aa batteries. .So in need 2 A output. Are there any suggestion for me?

1 year ago
• zidni

where i can buy the module? .. but if input 2.4 volt and current is 30 micro ampere, can work the module?

1 year ago
• Andrea Poma

Hi Kumar,
could you send me the gerber file?
@ andrea-poma@hotmail.com
Thanks

7 months ago

6 months ago
• md kamal ahamed

i need
@ 1-5 vdc to 5 vdc dc dc step up converter with 2000ma
@ intelligent emergency led light driver making circuit diagram . 230vac input and 4vdc utput. 3,7 or 4 vdc li ion battery back up.
ii want t make by myself. i need easy diagram with available parts.

4 months ago
• For 1. you will need a completely new IC and design, we don’t have such board. 2. We only have an emergency light with Lead Acid battery backup.

4 months ago