- Home
- Product Categories
- Level Shifters
- SparkFun Logic Level Converter - Single Supply
SparkFun Logic Level Converter - Single Supply
The SparkFun Single Supply Logic Level Converter is logic level and power supply translator in one small package. This little board breaks out the Texas Instruments TXB0104 4-bit bi-directional voltage-level translator with automatic direction sensing. With this logic level converter you will be able to use your 5V logic microcontroller with 3.3V sensors without the second power supply!
What makes this Logic level converter truly special is the fact that you can supply it with 3.3V and it will create the 5V - meaning you can use your 3.3V system, and convert directly to another 5V sensor - and even power your sensor or other board!
This logic level converter provides 5V to the high side of the TXB0104 and the low side is programmable to 3.3V, 2.5V and 1.8V. Please keep in mind that the default low side voltage is 3.3V.
- Dimensions: 28.5mm x 26mm (1.12in x 1.02in)
- Schematic
- Eagle Files
- Hookup Guide
- Datasheets
- GitHub
SparkFun Logic Level Converter - Single Supply Product Help and Resources
Single Supply Logic Level Converter Hookup Guide
August 9, 2018
The Single Supply Logic Converter allows you to bi-directionally translate signals from a 5V or 3.3V microcontroller without the need for a second power supply! The board provides an output for both 5V and 3.3V to power your sensors. It is equipped with a PTH resistor footprint for the option to adjust the voltage regulator on the low side of the TXB0104 for 2.5V or 1.8V devices.
Core Skill: Soldering
This skill defines how difficult the soldering is on a particular product. It might be a couple simple solder joints, or require special reflow tools.
Skill Level: Noob - Some basic soldering is required, but it is limited to a just a few pins, basic through-hole soldering, and couple (if any) polarized components. A basic soldering iron is all you should need.
See all skill levels
Core Skill: Programming
If a board needs code or communicates somehow, you're going to need to know how to program or interface with it. The programming skill is all about communication and code.
Skill Level: Rookie - You will need a better fundamental understand of what code is, and how it works. You will be using beginner-level software and development tools like Arduino. You will be dealing directly with code, but numerous examples and libraries are available. Sensors or shields will communicate with serial or TTL.
See all skill levels
Core Skill: Electrical Prototyping
If it requires power, you need to know how much, what all the pins do, and how to hook it up. You may need to reference datasheets, schematics, and know the ins and outs of electronics.
Skill Level: Rookie - You may be required to know a bit more about the component, such as orientation, or how to hook it up, in addition to power requirements. You will need to understand polarized components.
See all skill levels
The voltage divider equation and provided values in the schematic are screwed up. The purpose of R3 is to clamp down the output voltage so it does not go above 3.6V when R1 is removed or not present.
If you want to put in a fixed value, then you need to remove R3 and either populate R3 (SMD) or R1 (thru-hole) with the value provided in the schematic.
If you want to add a switch selector for the input voltage, then you want to keep the R3 in place because during switching you may leave the circuit disconnected and the output will rail blowing the IC. Thus, what you want to do is replace R3 with 48.7K resistor, that way the default is 1.8V when the switch breaks before makes. Then add your switch in series with the following values in place of R1, ie parallel with R3: 1.8V = open/inf ohm 2.5V = 39.2K 3.3V = 18.2K
FYI, from the pictures R3 isn't 13K, it's 12K.
What is the advantage of something like this over some MOSFETs with pull-up resistors to handle logic level translation???