Multiple Voltage Output (3.7V - 30V) from a 5V input

Thread Starter

Gaziorino

Joined Nov 3, 2021
5
Hello guys!

Ive ran into a probably simpleproblem but i cant wrap my head around it somehow.
Im looking for a circuit which converts a 5V, 3A Input into various voltages to simulate a batterypack.
I need that to verify functionality of other boards without having to use a batterypack all the time.

I measured all the voltages i need and made a chart in here1635925309824.png
Thought of using multiple isolated Dc-Dc Converters and put them in series,
but there might be a better way for that.
The current the outputs need is very low, measured about 0.06mA.

I hope someone knows a good solution for this simple looking solution :')

Cheers
 

Alec_t

Joined Sep 17, 2013
14,314
Welcome to AAC!
For such a low output current requirement you could probably use one 5VDC-30VDC boost converter and one or more potential dividers (resistors/potentiometer).
 

Thread Starter

Gaziorino

Joined Nov 3, 2021
5
Welcome to AAC!
For such a low output current requirement you could probably use one 5VDC-30VDC boost converter and one or more potential dividers (resistors/potentiometer).
Thank you!

I couldnt measure the current it needs while in operation, the 0.06mA is probably the standby current.
I looked into it and im guessing about 10-50mA is taken while in operation.
The Voltage regulator with resistors was my first guess, i just dont like that solution for the pcb, but i guess im stuck with that solution, haha

Thank you for your reply !
 

jayanthd

Joined Jul 4, 2015
945
I can design a very simple non buck-boost regulator DC power supply circuit for you but I need to know what is your max load side power requirement and what max Amps @ 5V your source PSU can supply. Also, you want multiple outputs in tapped format or one output port which can provide 3.7V to 30V variable voltages, that is any one voltage at a time on the same output port?
 

dl324

Joined Mar 30, 2015
16,923
Welcome to AAC!
Im looking for a circuit which converts a 5V, 3A Input into various voltages to simulate a batterypack.
I need that to verify functionality of other boards without having to use a batterypack all the time.

I measured all the voltages i need and made a chart in here
It sounds like you just need a buck-boost regulator to provide 3.7-30V from 5V.

What's the purpose of the pin numbers, signal names, cell connections, and resistances in the table? All we needed to know was the range of voltages and currents you needed from the 5V source.
 

Papabravo

Joined Feb 24, 2006
21,225
Welcome to AAC!
It sounds like you just need a buck-boost regulator to provide 3.7-30V from 5V.

What's the purpose of the pin numbers, signal names, cell connections, and resistances in the table? All we needed to know was the range of voltages and currents you needed from the 5V source.
Maybe he sought guidance from a serial troll.
 

Thread Starter

Gaziorino

Joined Nov 3, 2021
5
I can design a very simple non buck-boost regulator DC power supply circuit for you but I need to know what is your max load side power requirement and what max Amps @ 5V your source PSU can supply. Also, you want multiple outputs in tapped format or one output port which can provide 3.7V to 30V variable voltages, that is any one voltage at a time on the same output port?
Wow that would be really neat!

Im lokoing for an output for each voltage. So multiple outputs for the circuitry. The Input is an Type C 5V @ 3A. Max Load shouldnt be more than 100mA as i found out. Thank you lots for the offered help !

Cheers
 

Thread Starter

Gaziorino

Joined Nov 3, 2021
5
Welcome to AAC!
It sounds like you just need a buck-boost regulator to provide 3.7-30V from 5V.

What's the purpose of the pin numbers, signal names, cell connections, and resistances in the table? All we needed to know was the range of voltages and currents you needed from the 5V source.
The Pin Numbers are from a Molex microfit 24Pin connector which im trying to tap in my needed Voltages. The Last 4 Resistances are NTC Resistors which im emulating with a fixed resistor each. Currently were using 16 Battery modules to connect our CSC's to verify that they work before we build them in our Batterypacks.

The reason behind this little project im trying to put together is just to minimize our Testrig as we have it here. I wanted something compact to just plug a usb connector in to simulate our 16 Modules so we dont have 16 Modules just sitting around only to be used for testing our CSC's.
 

Thread Starter

Gaziorino

Joined Nov 3, 2021
5
Wow that would be really neat!

Im lokoing for an output for each voltage. So multiple outputs for the circuitry. The Input is an Type C 5V @ 3A. Max Load shouldnt be more than 100mA as i found out. Thank you lots for the offered help !

Cheers
I might need to add that a small capacitance of about 10-20nF is required for me to pass the LTC Open wire test. It sends a small current of 100uA to check if theres a battery connected. if not it sends out an error flag and the CSC doesnt pass the test. attached is the method it tries to check for the open wire

1636367379238.png
the LTC used is a LTC 6804 if you want to go through the datasheet.
Appreciate it alot that you give it a shot for this little project :)

Cheers everyone
 

dl324

Joined Mar 30, 2015
16,923
Wow that would be really neat!
By the comments from peer reviewers, you should have come to understand that what was proposed isn't possible.

To get voltages higher than your supply, you need boost. To get a voltage lower, you need buck. To get both, you need buck and boost.
 
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