Questions tagged [medical]
For applications in the medical arena that will come in contact with a patient. In general these applications need to satisfy international standards such as IEC60601. These applications have stringent patient isolation constraints, capacitive leakage constraints, mode of failure constraints, and voltage or current limits that can impose considerable design limitations.
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EKG active filter designs with single power supply
This is my beginners attempt at designing a EKG. I have printed out the PCB and attached all components to it to test it out. What I have observed are the following:
1. The outputs Vout1 as well as ...
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Difficulty in gaining Class II CE certification for an aluminium single-sided PCB
We have a product that consists of an aluminium single-sided PCB with micro-controller and LEDs soldered to the copper side. The PCBA is shaped so that it can be bent to fit over the scalp of the user ...
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EFT on powersupply AC input
My system I use 110 V to 36 V power brick (medical grade), and having hybrid cable which takes this 36 V and Ethernet and goes to the system.
I am testing the EFT as per 61000-4-4 (± 2 kV, 100 kHz ...
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Medical device on patient's bed..Cannot earth the Chassis..How to provide ESD protection?
We are developing a medical device, which will sit on patient's bed. So, the medical device chassis can't be connected to earth. The powersupply of the device is isolated (2MOPP and 2 MOOP), medical ...
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Can I use USB C 3.2 Gen2 connector for power and data for a medical application?
My class 3 medical system uses 36V (~100W), 100Mbps ethernet for communication. I am planning to use USB 3.2 gen2 connector and cables to simplify my cabling in the system, and to have EMC shielding ...
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The amplification factor of the EMG circuit did not meet expectations
I've recently embarked on a project to create a DIY EMG system and have been using Multisim for simulation purposes before finalizing the PCB design. Attached is an image of my EMG circuit. In this ...
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Safety of grounded and isolated AC in medical systems
Introduction
I try to make more sense of safety and reliability of grounded and isolated electricity. I divided the problem into 3 stages:
Power-transmission line
Household electricity
Electrical ...
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How do the input current bias and the driven ground circuits in OpenBCI Ganglion work?
I am trying to understand how the OpenBCI Ganglion board works, but I can't figure out how these two sub-circuits work. I'm sorry I'm not too familiar with op-amps.
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Are rechargeable li-ion considered primary batteries if charging is not available on the device?
We are designing a one time use medical device which we would like to power using a li-ion pack that would be charged only once at the time of manufacture.
For the purposes of compliance (IEC 60601) ...
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What does 2xMOPP really mean
I am a student and I am designing a medical device that has a type CF applied part.
I know the specifications that the applied part must comply (4kV of insulation, 8mm of creepage, <10μA patient ...
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What is the ideal wireless protocol that is best suited for wireless nerve impulse transmission? [closed]
I am working to develop a way to transmit nerve impulses wirelessly (or wired) past a break in the spinal cord. What would be the ideal protocol to effectively relay the signal? Even if the device was ...
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How is a mains-connected medical device made safe against electrocuting me?
I am in physical therapy now. Some of the devices are connected to wall power, and used for muscle electrostimulation. The patient information states that no single malfunction can connect me to 230V, ...
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Any theoretical reference for empirical equation for estimating oxygen saturation (% SpO2 = 110 - 25*R)? [closed]
The empirical equation used to estimate % SpO2 is based on the observation that the ratio of the red and infrared light absorbed by arterial blood (represented by R in the equation) varies linearly ...
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What is the safest way to control another circuit?
From my custom board with an MCU I need to connect to an Interlock Pin of another circuit. I have a lot of options, but I don't know what is better.
Using an optocoupler, but I'm afraid the output ...
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Difficulties with multiplexing PPG signal in pulse oximeter
I've designed pulse oximeter circuit. When one LED lights continuously, I got perfect PPG (Photoplethysmogram) signal.
Then I measure PPG while blinking LEDS, like that:
I got stuck. There is no ...
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Help with finding the type of output for a mems mircophone
I am using this MEMS microphone for a stethoscope project. The data sheet recommends the following interface circuit.
I can't seem to find where it states specifically that it is a differential output ...
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How do medical SMPS achieve lower Earth leakage compared to "regular" AC-DC SMPS?
When using a "regular" (i.e. not medical grade) AC-DC isolated SMPS in the following fashion, a strong mains common-mode voltage is created on the DC side due to - I believe - the stray ...
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What is the reference voltage of Vin- and Vin+ in this circuit?
I'm trying to make a PCB board to measure Electrocardiogram (ECG) signal. I have some doubts about the DC offset of the 2 input signals (\$V_{IN-}\$, \$V_{IN+}\$) with reference to analog ground. I ...
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How to convert the outputs from the MAX30003 and/or AD8232 ECG modules to millivolts (mV)
I have been working with the MAX30003 and AD8232 ECG modules for a while now and I am trying to figure out what the raw outputs from both modules correlate to. I cannot seem to find any information ...
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Difference between a normal tactile switch/pushbutton and a detection switch/pushbutton
What is the general difference between a normal tactile switch/push button and a detection switch/push button?
I have heard that if in an application, for example, a pushbutton has to be pressed for a ...
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AC filtering: Medical vs Standard Version
I am looking at that Schurter's AC power entry modules to choose a AC filtering module and at page 5 I noticed the differences between Standard version and Medical version:
Their only difference is ...
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Risk of getting shocked by ECG leads? [closed]
I have recently come into possession of a GE patient monitor (Eagle 4000) which looks structurally sound, probably decommissioned because of its age. It seems to work without a hiccup but I remembered ...
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Is there a standard equivalent to automotive standard AEC-Q200 for the medical sector?
I want to ensure components of high integrity characteristics are utilised in a design by a third party.
In the automotive sector AEC-Q200 can be stipulated, e.g. (https://www.digikey.com/en/product-...
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What is a good SNR for a medical device like a pulse oximeter?
What is a good SNR for a medical device like a pulse oximeter?
Is there a U.S. Federal standard for this?
Thanks!
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Voltage / amperage / setup for tingling sensation
There are small pens (powered by a single or double 1.5V battery) or other medical devices that upon touching your skin produce a tingling sensation.
Main question: I wonder to what voltage, amperage ...
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Medical electronic devices quality
Is there a special grade for electronic components made to be used in medical devices such as life support systems?
I have read in most data sheets that "this product is not to be used in life support ...
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Pressure sensor without using MEMS chips [closed]
I'd like to figure out how to make a pressure sensor for very low cost (essentially disposable), mass produced piece of medical equipment.
The problem: this can't use any parts which aren't already ...
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Developing a Medical Product Using AliExpress Modules
We are developing a medical product and we are using some modules that we got from AliExpress (www.aliexpress.com).
They are really cheap and gave us the same results with the modules which we made ...
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What type of ultrasonic transducers are used in medical ultrasound devices?
When I search on DigiKey for ultrasonic transducers, all I get back is the circular transducers that are sold for the various DIY projects. i.e. the picture below:
However, the "medical" ultrasound ...
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SMPS electrical noise issue
1I'm using class 2 medical graded SMPS in our device. So earth connection not recommended. When connecting SMPS to load (contains capacitive touch LCD),
touch function is affected by SMPS noise. When ...
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