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.
317 questions
3 votes
5 answers
625 views
Any reason the gate pull-down shouldn't be eliminated on an RP2040/RP2350 GPIO connection?
Regarding the practice of including a grounding resistor on the input of a MOSFET gate to prevent float conditions from biasing the MOSFET into the active region... Since the RP2040/RP2350 MCUs ...
- 139
2 votes
6 answers
1k views
When would we like to use a resistor here?
In Xilinx's 7 Series FPGAs Configuration User Guide (UG470), they say M[2:0] determine the configuration mode. Connect each mode pin either directly, or via a ≤1 kΩ resistor, to VCCO_0 or GND. Adding ...
- 717
1 vote
1 answer
58 views
Sensor power sequencing
I am trying to make a power up sequence for a sensor that requires 3.3V, 5V and 10V. 5V and 10V power should be applied after 3.3V. My PCB is powered by 12V, and I use STM32L4R5, connected to the EN ...
- 155
6 votes
3 answers
1k views
Relative Resistances of Pull-Up vs. Pull-Down Resistors
I’ve been reading the book “Complex Digital Hardware Design” by Istvan Nagy. On page 74 he writes PU [resistors are] typically 3 to 10 times larger resistor value than PD. On 3.3V signals a 10k PU ...
- 307
5 votes
4 answers
990 views
Pull-up and pull-down resistances technology in microcontrollers
I am making measurements for the characterization of pull-up and pull-down resistances in microcontrollers GPIO interface. I am currently working on a STM32 microcontroller, and in particular the ...
- 51
1 vote
1 answer
241 views
How to estimate pull up/down resistors for the digital pins of this IC?
Regarding this power multiplexer IC's the digital inputs D0 and D1, the input impedance of the D0 and D1 is not given. Only Input current at D0 or D1 is given as 1.4uA. So far I ended with the ...
- 1,622
1 vote
1 answer
115 views
Pull-up and pull-down resistors values
This is my first project: Do you think that all the pull-up and pull-dwn resistors value are good? Do the capacitor are oversized? Any suggestions about the circuit in general? Thank you :) Updates:
- 141
2 votes
1 answer
46 views
VNQ9080 input pull-downs
I'm using the VNQ9080 in a design and am undecided about adding pull-downs to the inputs. The inputs are controlled from a SX1509 I2C I/O expander which has the pins on HI-Z by default. I want to make ...
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