How to reduce the voltage from 5 to 3.3 volts?

Question

Arduino

Hello.
I need to power the wifi module esp8266. However, it is very demanding on power and will burn stupidly from 5 volts. Tell me how to reduce the current from 5 to 3.3 volts without using a step-down converter. I saw on the Internet that you can make a voltage divider from resistors, but I don’t know what values ​​​​to take.

Answer 1

no need to shaggy your grandmother and do something collective farming without understanding the basics :)
put a linear stabilizer at 3.3 V, for example LF33 .
their million options - google "voltage stabilizer 3.3v" select the current consumed by the module (preferably the maximum current consumption). current margin and cooling to taste.

Answer 2

If you definitely want with a resistor, then a parametric stabilizer circuit is suitable - a 5-6 Ohm resistor with a power of 1 W in series with the load and a 3.3 V zener diode in parallel with the load, anode to minus. But it is better to take a ready-made linear stabilizer, as already written above.
ps The denominations seem to be correct, but first check on the cats :))

Answer 3

probably meant the following. we connect resistors with resistances R1 and R2 to the source in series. wifi module is connected in parallel with the resistor R1. We choose the ratings so that:
A) R1/(R1 + R2) = 3.3/5
V) the power dissipated by the resistor R1 (P1) is at least an order of magnitude higher than the maximum power consumed by the module. P1 is calculated by the formula
P1 = 25V ** 2 / (R1 + R2) * R1 ** 2
But why do this?

Answer 4

It’s better to immediately buy a ready-made scarf on Ali with a USB / UART CH340 converter and an AMS1117 3.3 voltage regulator.
Stubs:
https://www.chipdip.ru/catalog/ic-stabilizers?x.15...
or here
https://www.chipdip.ru/catalog/ic-stabilizers?x.57...
on LM317T - hardelectronics.ru/lm317t-sxema-vklyucheniya.html
or Ali - https://ru.aliexpress.com/af/dc-3.3v.html?SearchTe...
.

Answer 5

* If there is nothing at hand, but you need it urgently - look for a led flashlight. Often there are 3 volt diodes. If the stub is suitable there, put it on. The card reader can also be with a converter. You apply 5 (usb) to it, and 3 for the card comes out from it. You can collect UFOs in an industrial dump.
* If you can not economically - pick up the light bulbs - you get a divider. If batteries - you can make a separate battery for the transceiver.
* If you buy batteries for 1.24 volts, then you can connect them in series -
charged - 1.24 - 2.48 - 3.72 - 4.96
dead - 1.02 - 2.04 - 3.06 - 4.08
For 1.5 volt batteries. (1.5-3.0-4.5)

(-) |-[XXXX}--[XXXX}-|-[XXXX}-| (+)
 GND                   3.0..3.3    4.5..5.0

* And in general, the microcontroller should work with 3.3. If there is a stub, then bypass it. (like you have an external stub, one for both assemblies). Most likely he will earn from 3.
(!) - in addition to the power supply of the module itself, there is also its sensitivity to signals. So a 3 volt controller is also better. You can of course: (gnd) - [resistor] - (wifi) - [resistor] - (mk) but not the fact that it will be reliable.
Battery operated-
(-) |-[XXXX}--[XXXX}-|-[XXXX}-| (+)
GND 3.0..3.3 4.5..5.0

Answer 6

No stabilizer.
ESP8266 consumes up to 200 - 250 mA, which is a lot for a circuit with a zener diode. It's ridiculous to talk about the divisor in this case.

Answer 7

Here, in a good way, a pulsed buck converter is needed.
For example, TPS562200 www.ti.com/lit/ds/symlink/tps561201.pdf
Or a little more ancient lm2596, based on which there are a bunch of Ali modules.

Answer 8

5V to 3.3V for DC-DC