Level shifting is the process of converting between different logic levels. E.g. from 0-3.3 V logic to 0-5 V logic

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44 views

Arduino: RS232 Level Shifter or RS2323 Breakout needed?

I am trying to establish communications between an Arduino Mega2560 (Master) and a customised controller (Slave) via a Master-Slave RS232 link using Modbus RTU. The communication should be ...
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0answers
42 views

PWM to proportional bipolar control with push-pull amplifier. Need input and opinions

I'm putting together a circuit to control a (small wattage) TEC device in a bipolar manner. The idea is to have a micro controller put out a 3V3 PWM signal, level shift it between +- 3 V and filter it ...
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2answers
163 views

Microcontroller PWM to bipolar push-pull amplifier issues. (level shifting)

I'm trying to design a circuit that allows a micro controller (arduino) to control a voltage to a load. The load voltage needs to be bipolar in nature (+- 3 to 5 V) for use in controlling a TEC. My ...
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1answer
52 views

Sense Automotive 12V Circuit from 3.3V microcontroller safely

I want to sense a circuit state in an Automotive circuit (12V nominal) from a 3.3V microcontroller (MSP430Gxxxx). The circuit is normally 12V (or VBat) until either the Wireless ECU or a Door Key ...
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1answer
60 views

Purpose of Level shifter in charge pump

Why is there a need for level shifter in this circuit (charge pump)?
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2answers
1k views

What is the best way to convert 1.8 V to 5 V?

I connected HC-SR04 ultrasonic sensor, to single-board computer BeagleBoard-xM. Trigger pin requires 5 V DC. However, control pins of BeagleBoard-xM can provide only 1.8 V DC. What is the best way to ...
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5answers
482 views

Simplest uni-directional level shifter (3.3V -> 5V)

I want to drive a WS2801 LED strip from a Raspberry Pi GPIO. I have connected the MOSI and CLK pins directly to drive the LED but it is not working as the WS2801 datasheet says that a high level is ...
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2answers
106 views

Random flashing on WS2812B LEDs

I'm trying to drive a strip of WS2812B LEDs with a Beaglebone Black(revC). Because the LEDs expect a data signal at 5V and the BBB outputs at 3.3V, some sort of level shifting is required. However, ...
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1answer
88 views

Is it safe to use a bus buffer as level shifter?

I am currently using SN74ABT5402ADW as a buffer and level shifter for my ADC, however, the datasheet does not explicitly say that it can be used as a level shifter. I provide it with 5V power, but the ...
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2answers
282 views

Can I use 74HC14 or NPN transistor instead of MOSFET as level shifter

I have SN74HC14 or BC548 / 2N2222 transistors. I need level shifter for I2C between arduino and RPi. Here's simple circuit from the internet Problem is I don't have any MOSFETs. Can I use NPN ...
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1answer
90 views

Level Shifting & Amplification

I am trying to design a crane load (Weight) measuring unit using motor current measurement technique. For some reasons we can't use load cells here. Part of schematic I have drawn here An air core ...
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4answers
198 views

Connecting a 9V IC's I2C interface to 3.3v Arduino DUE

I need to connect a TDA7312 to Arduino DUE's I2C interface via SDA/SCL. TDA7312 operates on 9V, Arduino DUE is 3.3v. Is it possible to safely connect it, without burning it? Or what should I use ...
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1answer
145 views

op amp level shifter no input situation

I tried out op-amp level shifters on web. The ones recomended here as well but there is a problem when no input applied. The output voltage is no seperable from the case voltage applied. As i ...
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1answer
57 views

CD 4504B from 12 V digital to 5 V digital level shifting [closed]

I need to translate 12 V / 1 mA to Arduino UNO digital input. Is CD4504B a good choice? Because I already have one...
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1answer
158 views

I2C - connecting 5V device to 3.3V host

Is it safe to connect any 5V I2C slave device to 3.3V host? I know, that DS1307 realtime clock can be connected to Raspberry Pi (3.3V IO), because DS1307 just pulls down data lines and 5V voltage ...
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1answer
195 views

MOSFET on Arduino Uno

What is wrong with this circuit? I've performed the following tests in my circuit: When I set the controller output pin PD7 to HIGH, the source/drain voltage is 0V (measured with oscilloscope). ...
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2answers
137 views

Voltage shifter distorts signal

I am trying to downshift a 5V TTL signal to 3V logic signal using NTB0102 level shifter. The connection is described below: However, my oscilloscope measurements are distorted. Even the input ...
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1answer
88 views

BSS138 levelshifter draws 35-40mA current when one side is grounded?

I completely rewrote my question as I found the source of the issue is related to the level shifter only. This is the circuit for a 3.3V to 5V bidirectional levelshifter, used frequently. My ...
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1answer
163 views

op amp level shift circuit diagram? [closed]

Can someone please help me with explaining the op amp level shift functioning with circuit diagram? Thank you
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2answers
75 views

Driving a load on negative rail with a positive signal

I want to turn the LED on when the 5V pulse is high. I expect a simple circuit consisting of two or three bipolar or MOSFET transistors similar to the erroneous one in the image above. I don't want ...
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1answer
66 views

NXP i2c temperature probe locking up

I have an issue with an NXP SE95 temperature probe that has been working just fine up until now on other systems. At some point, either on boot or soon after, the probe will have some sort of meltdown ...
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1answer
94 views

Why would a 5V input to a 74HC04 pull it's V_CC from 3.3V to about 4V

I have the following circuit: simulate this circuit – Schematic created using CircuitLab The SN74HC00 (from TI) has input clamps, so I am expecting the 5V logic input to be clamped to ...
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3answers
288 views

3V3 to 5V level conversion

I'm currently working on the development of some measurement equipment. For conversions I use a small ARM which runs on 3V3 and to display the results I use a graphical display running on 5V. This ...
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1answer
101 views

FET level shifter for serial does not work with inline resistor for safety

For a voltage change on a serial line I'm using a common level shifter design which uses a FET (BSS138 in this case) as so: I have two of these - one for RX and one for TX. I should add that I'm ...
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1answer
676 views

Arduino <-> BBB UART issues using bi-directional level converter (5v to 3.3v)

I am having a strange issue interfacing between an Arduino and BeagleBoneBlack over UART. The Arduino is 5v logic, and the BBB is 3.3v logic, so I'm using a bi-directional logic level converter from ...
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4answers
1k views

What is the simplest op amp level shifter?

What is the simplest op amp level shifter? That is, no gain and both inverting and non inverting configurations, for AC coupling
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1answer
181 views

Understanding 74LVC245 datasheet and current source/sink

I'm using a SN74LVC245A (datasheet) to shift 5V TTL down to 3.3V so I can read the signals with a Raspberry Pi. However I am getting really weird results (a 60Hz input signal is picked up by the Pi ...
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1answer
52 views

making sense of HCT ACT cmos “addional supply current”

I'm trying to make a low-current level shifter from low voltage (~2V) CMOS up to 5V CMOS. I had the idea to use TTL-compatible CMOS gates in the HCT or ACT families. But this line in the 74HCT04 ...
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2answers
218 views

TTL to +/- 12V conversion - what's a better way?

The context here is the pilot generator for a J1772 EV charging station. The specification calls for a 1 kHz +/- 12 volt square wave with varying duty cycle. The output is sent through a 1 k resistor ...
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2answers
427 views

Is a N-Channel Mosfet save/reliable for level shifting UART from 3V3 to 5V?

I am busy with a design that needs to connect a Raspberry Pi to an Arduino via UART. Previously I have designed a circuit that worked okay. But now I want start using SMD components and is planing ...
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3answers
114 views

I2C Level translation

In our current design, we have two devices which communicate with each other using I2C. But their I2C logic levels are different, so we need to use a level translation? Can I use a simple level ...
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2answers
74 views

Low profile i2c level shifting solution

I have a system that involves two boards and i2c communication between them. One of the boards uses 2.8V for i/o (including i2c) and the other 3.3. The 3.3V board is always the master and the 2.8V ...
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1answer
38 views

GPIO pull up to different level

I am using MSP430F235 which is supplied with 2.5V on DVCC. So, all its I/Os will be in 2.5V level. Now, I want to enable a LDO in which EN pin is tied to a different level (>2.5V is the battery supply ...
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2answers
193 views

Shift 0-1.8V logic to 0-5V logic

I'm using BeagleBoard-xM McSPI to drive an MCP42050 digital potentiometer. Before using the SPI chip itself I'll try bitbanging through 3 GPIOs (but my question relates to both configurations). BB ...
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0answers
135 views

Level shift and amplify

I searched around the forum and found this post: Analog voltage level conversion (level shift) I built a dinamic motion seat with an Arduino, H-Bridge and 2 wiper motors. The wiper motors are acting ...
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1answer
286 views

IC to interface between digital switches (12V) and microprocessors (3.3V)

I am working on an automotive general purpose ECU where I need to interface 12V digital inputs with a µC (3.3V). The PCB space is limited, so I am searching for a single IC as an interface between ...
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1answer
337 views

Converting 3.3v logic level to 5v using octal bus transceiver

I'm using the Raspberry PI to communicate with various sensors and other circuits that input and output 5V logic level. The Raspberry Pi itself has 3.3V GPIOs, so i need to convert the logic levels. ...
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1answer
465 views

i2c over gpio - level shifter

I'm quite new to this. I have just basic background in electronics. So I would appreciate an advice from someone more experienced. I would like to connect an i2c display to my tp-link wr703n (ar9331) ...
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3answers
152 views

Looking for a level translator for single duplex serial bus

I have a 3.3V UART (two pins) plus a direction selector pin (also 3.3V.) I need to talk to and listen on a single duplex serial bus at 5V with 20 mA drive strength. The signaling rate is 3 Mbit/s, ...
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2answers
136 views

Bigger resistors in place of a level shifter on a SD reader?

This item, a MMC/SD card reader module with 3V3 LDO and 10k pull-ups, has a schematic with an interesting tidbit in a big red box: Change R3, R4, R5, R6 resistance [from 2R7] to 330-470 [ohms], ...
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1answer
126 views

Signal level shifting from +-15 to +-25

I have a bipolar signal with a peak to peak voltage of 30V (+-15V). I need to shift the signal level to be (+-25) with a dual supply voltage rails of (+-25). Do you have any ideas or a circuit ...
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2answers
3k views

Single transistor level up shifter

I need a simple, single directionnal level shifter for 3.3V -> 5V conversion. There are many options on the internet, some using a logic ic and some using 2 NPN transistors (converter and inverter), ...
2
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1answer
8k views

Step up 3.3V to 5V for digital I/O

I normally use an Arduino for my projects because it has 5V inputs and outputs and has 5V Vin so that makes life very easy when interfacing with 5V components. For this project I want to use a ...
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5answers
2k views

How can I switch a high-side transistor from logic referenced to ground?

Problem: I have a logic signal (represented by SW1), say from a microcontroller, that is either 0V or some low voltage, maybe 5V or 3.3V. I have a higher voltage supply (V1) and a switching device ...
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2answers
2k views

3.3V <-> 24V interface

I need to interface an ARM µC (BeagleBone Black) with a 24VDC system. 24VDC sensors and 24VDC actuators should be connected to the BeagleBone Black. I am wondered how to do this. I have found a ...
2
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2answers
2k views

GY-521 MPU-6050 + Arduino nano - Logic converter or not?

I bought this MPU-6050: link (marked as "GY-521" on the board) According to the manufacturers' site, the sensor logic level is 3.3V (though the eBay page says ...
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2answers
322 views

Using BSS138 in Level Switcher

I am trying to interface 1.8v UART and 3.3v UART using NXP app note here. Unfortunately, my circuit does not perform as expected. I am using BSS138 as mentioned in Adafruit and Spakrfun. When I ...
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3answers
100 views

Connecting devices with different logic levels

The following figure is taken from this link, where the author explains how NOT to connect devices having different logic levels He says that: Directly connecting the devices together (see ...
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2answers
369 views

Common Gate Level Shifter

I am in the need for a high-side load switch and came up with the following schematic. High-Side voltage levels and current vary between 5-12V / 2 A max. The high-side PMOS (SI5509DC) is rated for 20V ...
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2answers
485 views

Bidirectional Level Shifter without IC

I'd like to connect R-Pi serial to PC's RS232 port without IC (such MAX3232), using only diode (thus block negative voltage to 0V), voltage divider resistors, and common BJT. For TXD (RX from R-Pi ...