Questions tagged [sinking]
The sinking tag has no usage guidance.
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"Source", "sink" or both?
Having solved the mystery of "pulling" and "pushing" devices, it would be interesting to do the same with "sourcing" and "sinking" devices.
Background
A ...
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Microcontroller sinking current from another MCU
I have two microcontrollers, the beloved ATmega328p and an ATtiny85. The ATtiny85 does power management (toggling power to main MCU, get buttons clicks, and other things). The ATtiny85 disconnects VCC ...
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Sinking an input when pulses are above a certain frequency
I'd like to use a liquid flow meter of type YF-S401 at 12VDC. It produces 1.7-35k pulses per minute (rise time: 0.04us, fall time: 0.18us).
I want to trigger a sinking input of a controller board if ...
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PNP as an inverting sink
I'm using a 74LS137 to drive a 7 segment LED (common anode.) Since it's a sink, it "inverts the demux outputs" as desired:
I want to wire-OR two outputs, but you can't do so directly for ...
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Will this optocoupler circuit work for sensor and DC motor?
I am working on a project in which I need to operate a DC motor and some ultrasonic sensors.
I want to operate the motor using motor driver DRV 8871 by giving logic signals and read sensor value on ...
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How to read this figure (UDN2981 max current)?
This question is related to this question: why-are-the-pins-of-an-udn2981-related?
In the UDN2981 datasheet, the figure below shows the maximum current (page 14, bottom left picture).
Does this ...
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LED ULN2803 thermal / heatsink questions
I'm intending to use LEDs of 5mm, which have a max forward current rate at 30 mA, or a value of 100 mA, with 10% 1 kHz duty cycle, in a circuit like the one below except some changes:
STM32F103C8T6 ...
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Choosing pulldown resistor for 74LS86
I am trying to build a half adder using a 74LS86 XOR gate. Initially I connected both input pins that I am using (9 & 10) on the 74LS86 to the ground rail using 10K ohm resistors. I then connected ...
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Matching sensor output with PLC input
I am trying to add a height captor for a line of my production where I work. I found this Banner captor (QS30LLPQ) and it has 2 bipolar discrete outputs (PNP and NPN). Now, I am trying to decide which ...
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LED circuit stopped working when expanded
I built a small prototype as shown in my diagram with the Si926 n-FET, 250 ohm pull up resistor. In my prototype board I have only 4 channels connected (only two shown). Only one LED is ever turned on ...
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Rotary Encoder - Power Source for small Fork Light Barriers with NI 9401 [closed]
Task
In order to measure the angle and calculate the angular velocity and acceleration of a large metal wheel with a rotational frequency \$f = 0.01 \ldots 1.00~Hz\$, I try to build a custom rotary ...
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LED switch with externally controlled current from sinking output
My device has sinking output (Vcc=3.3V), the LED current (and voltage) is controlled by another device (a voltage controlled constant current source) as indicated at VLED. The LED IV curves (as ...
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Oops! N-channel Mosfet on sinking output
I have designed a simple circuit to drive LEDs using a MAX6964 I2C LED driver/GPO chip. Unfortunately, I somehow missed missed that the outputs are open-drain current-sinking outputs. This is not ...
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Is it possible to sink and source from one output pin using a darlington driver
Sinking and sourcing with a darlington driver
I asked a question about sinking and sourcing LEDs while using a darlington driver. The images were slightly unclear so i have redrawn it. I had too many ...
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How to increase microntroller pin Source and Sink Capacity
I'm working on a project but I've hit a block now. I need to drive a total of 169 LEDs using 26 pins at worst case all may be ON at once. I'm afraid that this may fry the MCU since 200mA is absolute ...
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