Power

BSS138 Level Shifter

MOSFET-based bidirectional level shifter module used for I2C 3.3V/5V conversion.

China-madeGenericActiveModerate

Best For

Projects needing Level shifting and I2C with a commonly available power part.

Avoid If

You need production-grade certainty without checking the exact module vendor, pinout, and library maintenance status.

Quick Decision Notes

BSS138 Level Shifter is indexed as a power part from Generic. ChipScout tracks it by practical maker-facing dimensions: interfaces, library readiness, estimated price, field-level sources, and whether the page is strong enough for selection rather than only lookup.

Technical Specifications

FunctionLevel shifterSource: Generic
Channels4 commonSource: Generic
DirectionBidirectionalSource: Generic
UseI2C / GPIOSource: Generic

Common Use Cases

  • Maker prototypes
  • Low-cost modules
  • Educational hardware

Known Issues

  • Breakout boards may use different pin labels or regulator choices
  • Clone modules can differ from the original datasheet part

Interfaces and Library Support

Interfaces
I2CGPIO
Wireless
None
Voltage
3.3V
Libraries
Arduino verifiedMicroPython pending
Data Integrity72% confidence
Sourcehttps://learn.sparkfun.com/
Last verified2026-05-20
Core specsVerified
PinoutAvailable
Library supportChecked
Price rangePresent
Found a wrong spec?

Every field is meant to be source-backed. Corrections should include a datasheet URL, vendor page, module photo, or reproducible library test.

Submit correction

Source Resources

Pinout Table

VCC3.3VPower the module from a rail that matches the breakout board, not just the bare IC.
GNDCommon groundConnect ground between the controller, sensor/module, and external power supply.
SDAMCU I2C dataUse pull-ups appropriate for the board voltage; many modules already include them.
SCLMCU I2C clockKeep wiring short for breadboard prototypes and lower bus speed if unstable.
SignalMCU GPIO / ADCUse a digital input, output, PWM, or ADC pin based on the module output type.

Pinout is not yet source-verified. Use the table as an integration checklist, then confirm exact pins against the module vendor page before wiring hardware.

Common Wiring

VCC

Power the module from a rail that matches the breakout board, not just the bare IC.

GND

Connect ground between the controller, sensor/module, and external power supply.

SDA

Use pull-ups appropriate for the board voltage; many modules already include them.

SCL

Keep wiring short for breadboard prototypes and lower bus speed if unstable.

Arduino Example

#include <Wire.h>

void setup() {
  Serial.begin(115200);
  Wire.begin();
  Serial.println("BSS138 Level Shifter I2C wiring smoke test");
}

void loop() {
  // Replace this with the maintained BSS138 Level Shifter library call.
  Serial.println("Check BSS138 Level Shifter on the I2C bus, then read a sample.");
  delay(1000);
}

MicroPython Example

MicroPython support is pending. Treat community scripts as prototypes until a maintained driver is linked and tested on a known development board.

Recommended Development Boards

ESP32-C3 development board

Low-cost Wi-Fi/BLE board with enough interfaces for most sensors and modules.

Arduino Uno R4 / compatible

Good baseline for beginner wiring and library validation.

Raspberry Pi Pico W

Practical MicroPython target for I2C, SPI, UART, PWM, and ADC experiments.

Alternative Model Reasons

18650 Battery HolderPowerCompare this option when price or module availability is the deciding constraint.
74HC595PowerChoose this when MicroPython support is required for fast prototyping.
A4988PowerThis alternative currently has stronger source coverage and confidence in ChipScout.
AMS1117-3.3PowerThis alternative currently has stronger source coverage and confidence in ChipScout.

Common Questions

What is BSS138 Level Shifter best used for?

Projects needing Level shifting and I2C with a commonly available power part.

Does BSS138 Level Shifter support Arduino or MicroPython?

BSS138 Level Shifter has verified Arduino support and MicroPython support pending verification.

What interfaces does BSS138 Level Shifter use?

BSS138 Level Shifter lists I2C, GPIO; wireless support is no wireless protocol.

Compare BSS138 Level Shifter vs 18650 Battery Holder

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