Can I provide 5V to LM1117 ?

I have to power PIC18LF45K80 (3.3V device) and SIM900 board (3.3V board). The power source is a 3.7V 2000mAh Li-Po battery from mikroElektronika. The system will be battery powered. To provide 3.3V to both the boards I am thinking of using a 3.3V zener with the 3.7V battery. Is it ok to use the zener. Will this result in battery power loss ?

I am making two versions of this system. One will have LCD and Keypad and this is for shops (like Jewellery shop) and another without LCD and Keypad. The one with LCDs use 3 to 24 PIR sensors. The one for automotive uses vibration sensors. I need both to be battery powered hence I have purchased SIM900 board working at 3.3V and also PIC18LF45K80. This is important because if used in shops then if the system doesn't use battery but work from mains then the system will not work if there is a power cut.

Also can I use a 11.3V 5000mAh Li-Po battery pack and connect it to IN of LM1117 and take 3.3V out for SIM900 and PIC18LF ? Will the battery provide 2A burst voltage to GSM while sending SMS ?

Which is better 3.7V 2000mAH battery with 3.3V Zener ot 11.3V 5000mAh battery with LM1117 ? Will LM1117 handle 2A current ?

Why do you not use a dc-dc converter? If you go from 11.3V to 3.3V at 2A you will waste (11.3-3.3)*2A=16W. For this you could use something like lm2673S-3.3 or a complete module.
If you go from 3.7V to 3.3V with a zener it is ok only for small currents but you will lose the power disipated is the resistor and zener. Or you could use a DC/DC again like ADP3050ARZ-3.3 that wil go from at least 3.6V to 3.3V. But that does not leave much room for dropping voltage of your battery.

would be convenient if you posted links to the devices..........

Ok Kam. Here are the links for the products mentioned in threads

this and

https://www.edaboard.com/threads/331027/
https://www.edaboard.com/threads/331023/



https://www.mikroe.com/mikromedia/pic32/
https://www.mikroe.com/mikromedia/stm32-m4/

https://www.mikroe.com/mikromedia/shields/mikrobus/
https://www.mikroe.com/mikromedia/shields/battery-boost/
https://www.mikroe.com/click/rtc2/
https://www.mikroe.com/click/fm/

https://www.mikroe.com/click/speakup/

I need a usb charger similar to this

https://www.mikroe.com/add-on-boards/power-supply/usb-charger/

which can charge a 5V 3000mAh Li-Po battery. It is for another product. It is Arduino UNO and LinkSprite SIM900 modem based product. It is GSM Alerter. I want the product to be compact and sealer so that nobody tampers with it. It is for two wheelers. I have written the code using mikroC PRO AVR Compiler and everything is working fine. All I need is a 5V 3000mAh or more battery with a charging circuit. The unit will be clamped below the vehicle seat. When the vehicle is parked then all that is needed is to press the button on the unit and the system will activate after 2 minutes. Then is vehicle movement is detected it sends SMS. It can be deactivated by pressing the same switch or by sending SMS "Deactivate" from the owner mobile.

milan.rajik said:

It is for two wheelers. The unit will be clamped below the vehicle seat. When the vehicle is parked then all that is needed is to press the button on the unit and the system will activate after 2 minutes. Then is vehicle movement is detected it sends SMS. It can be deactivated by pressing the same switch or by sending SMS "Deactivate" from the owner mobile.

Click to expand...

Sounds sort of like a **broken link removed**, which as you can see there are already products on the market.

Here are the links for the SIM900 mentioned in post #1.

I am getting this SIM900 board customized for my requirement. Vehicles will have vibrations and I don't want connectors to disconnect. So, I am getting a PIC18LF46K80 PDIP on the board. There will be only one 2 pin relimate connector for connecting battery power. I have requested then to provide battery charging circuit on board. I am thinking about using Machine tooled 40 pin DIL Socket for PIC18F. Is it ok to use Socket? Can PIC18F come out of the socket due to vibration in vehicle ? I thought that PDIP version will be easier to replace. Should I go for SMD version of PIC18LF46K80 ?

https://www.rhydolabz.com/index.php?main_page=product_info&cPath=184_185&products_id=1076



Here are the links for SIM900 used in Arduino based products.

https://store.linksprite.com/sim900-gprs-gms-shield/
https://www.geeetech.com/wiki/index.php/Arduino_GPRS_Shield

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Thanks for the link ads-ee

It's a 129 USD product for bicycle. I am designing for bikes and scooters. No body in India will buy a 129 USD product in India for two wheelers. 60 USD product will be ok.

Some are manufacturing a low quality product for two wheelers and their manufacturing cost is USD 33 and they are selling it for USD 80.

I am planning a USD 50 product which will be sold for USD 70.