Questions tagged [pulldown]
A pull-down resistor brings a line down to a voltage (typically ground potential) when the line isn't being driven to a specific voltage. It prevents the line from "floating" with an unknown voltage on it.
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How long is it okay for pin to be floating during MCU startup?
I’m using an ESP32-S3 to communicate with a 5V-only LCD module with an i8080 parallel bus interface. To shift the levels, I’m using the SN74LVC8T245 bidirectional level shifter. This means I can both ...
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Question about DC pin in USB C module. Is it possible to connect two USB C and Micro USB connectors in parallel to charge the same battery?
Good morning everyone,
I received help from several members of this page regarding my goal of adding a USB-C connector to a tablet that already has a micro USB connector for charging. After ...
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Are the data pins necessary on a mini USB connector used only for charging a tablet? Is the ID pin used for OTG?
I have an older tablet, and I plan to replace the charging-only micro USB connector (which does not transmit data) with a USB-C connector. However, upon examining the pinout, I noticed that the two ...
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How should I select the ohm values for pull-up and pull-down resistors in a device with a USB Type-C connector used solely for power
Good morning, everyone. I am exploring the transition of the receptacle from a micro USB connector to a USB Type-C. Initially, my plan included implementing both sink and source capacity. However, ...
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Replace micro USB tablet connector with USB C
I'm considering upgrading my dad's old tablet, which currently has a micro USB connector. The issue arises from his habit of frequently misplacing the charger, and I'd prefer not to rely on an ...
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Why is pull-down resistor on low-pulse triggered relay input not working?
I have a low-pulse triggered latching relay board (datasheet for individual relays, link to board). Whenever I plug-in, or un-plug my Arduino Nano's USB cable the relay changes state (sometimes ...
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Inverting Op amp do i need a pull down resistor
So im currently working on a circuit and im not too familiar with inverting Op amps and therefore am asking for some help below is my circuit its the latter half of the circuit and just wondering if i ...
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ESP32 Boot Mode
I am using ESP32-S3-WROOM-1-N16R2 in my design. In ESP32-S3 development board schematic they connect boot pin GPIO0 with external switch.
The reference image of dev board link is below:
https://dl....
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SCL line Pulled Low all the time
I have made a custom PCB with nRF52840 and Three slave Devices(IAM-20380 Gyro), (ADXL372 Accelerometer), (VCNL4040 Proximity ) Sensors. All slaves are connected to one I2C Bus When I plug only power ...
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Ground detection circuit
I'm designing a circuit containing a button with a pull-up/pull-down logic depending on whether I'm grounding a header. The button triggers a GPIO that will detect if the header is grounded thanks to ...
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Loop in Arduino LED circuit, with push-button for mode switching, stuck when moving to Mode 3
I have been working on an Arduino project: 4 LEDs connected on a breadboard, with series-parallel circuits, that are being controlled by push button. The desired behavior is to start in OFF mode, and ...
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How big a pull-up resistor is needed to pull up an internally pulled-down GPIO (ESP32-C6)?
I'm feeding a BCD diode matrix of switches with Vcc at 3.3 V and running the BCD outputs into GPIOs on the ESP32-C6. The plan is to set each GPIO input to internal pull-down so I can pull it up ...
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Combining voltage divider, pull-down resistor and low-pass filter in analog sensor signal
I am integrating a KP236N6165 analog absolute pressure sensor from Infineon.
They recommend the following circuit :
My microprocessor which receives the signal uses 3.3V logic and is not 5V tolerant ...
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TC4420 MOSFET Driver Output Latching Behavior
The TC4420 push-pull MOSFET driver seems to latch its output on if the low input signal isn’t pulled to ground. The signal I am using for the input is purely an on-off signal where the off part of the ...
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Pull-down resistor with LED on a logic input
Imagine I have the following circuit:
A register (74LS377N) has the inputs connected to a bus.
In the picture, BUS0 is pulled down with a 10k resistor, so if nobody outputs to it the register will ...
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