- Wed Aug 08, 2012 8:50 am
#148263
I want to provide both 5V and 3.3V to my circuit from two 3V lithium-ion coin cells. I'm thinking of one of two ways.
1) Have the batteries provide power to two voltage regulators in parallel (5V reg and 3.3V reg).
2) Have the batteries provide power to the 5V regulator, which then uses a voltage divider to drop down to 3.3V.
The 5V is being used on a few ICs in the circuit. The 3.3V is used to power an XBee radio.
Conceptually, since the voltage is already being regulated through the 5V regulator, I would think it's okay to power the XBee radio through a voltage divider after decoupling since the voltage is already maintained. Plus it would certainly save battery power. However, I may be oversimplifying this and would like some input from you guys.
1) Have the batteries provide power to two voltage regulators in parallel (5V reg and 3.3V reg).
2) Have the batteries provide power to the 5V regulator, which then uses a voltage divider to drop down to 3.3V.
The 5V is being used on a few ICs in the circuit. The 3.3V is used to power an XBee radio.
Conceptually, since the voltage is already being regulated through the 5V regulator, I would think it's okay to power the XBee radio through a voltage divider after decoupling since the voltage is already maintained. Plus it would certainly save battery power. However, I may be oversimplifying this and would like some input from you guys.