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## Voltage Level Shifter 3.3V to 5V | Level Converter 5V to 3.3V

This page describes voltage level shifter from 3.3V to 5V conversion. It mentions level converter circuit to convert 5V to 3.3V including its benefits and drawbacks.

Introduction: There are various methods to convert voltage from one value to the other value. The common techniques are as follows.
• Using simple resistance divider technique
• Using MOSFET
• Using bi-directional logic level converter

### Voltage divider method using resistors 5V to 3.3V The figure depicts simple method using resistors to derive one voltage value from the other value. In this case we will demonstrate 5V to 3.3V conversion.
Vout = { Vin * (R2/(R1+R2)) }
Above formuls is used in the following calculator.

The voltage converter circuit can be used to interface arduino which operates at 5V with ESP8266 which operates at 3.3V. This circuit works with slow signals. It is not very reliable. Hence most of the designers prefer bi-directional logic level converter module which is available at very cheap price.

### Voltage divider calculator

Following calculator can be used to convert one voltage input to the other. It is referred as voltage level converter.

#### INPUTS

Input voltage (Input #1) :

Resistor, R1 in KOhm (Input #2) :

Resistor, R2 in KOhm (Input #3) :

#### OUTPUT

Output voltage (Output #1) :

EXAMPLE voltage level converter :
Voltage input = 5V, R1 = 1 Kohm, R2 = 2 KOhm
Voltage output = 3.3V

### Using Bi-directional logic level converter The figure depicts logic level converter. It is bi-directional which converts voltage from 5V to 3.3V and vice versa. The device is I2C based and it consists of 4 channels. As shown "HV" pin refers to High voltage i.e. 5V where as "LV" pin refers to Low voltage i.e. 3.3V. The 8 channel bi-directional logic level converter is also available for enthusiasts and circuit designers. The circuit can be used as common digital interfaces for unidirectional and bidirectional use.

Following are the technical specifications of logic level shifter.
• Mutual transform between 5V TTL and 3.3V TTL
• Circuit converts voltage level as low as 1.8V to as high as 5V and vice versa.
• Supports digital interfaces such as SPI, I2C and asynchronous TTL serial.
• It can be used with microcontrollers, Raspberry PI, Arduino etc.

### Voltage level shifter 3.3V to 5V using MOSFET The figure depicts simple circuit to shift voltage from 3.3V to 5V and vice versa. This MOSFET based circuit is referred as voltage level shifter. The circuit can be used as bi-directional voltage level converter.

The component bi-directional logic level converter can be purchased from Robu.in in INDIA or from Sparkfun.com in USA.