Power net portal is a special schematic object used to define a power or ground net. Power ports allow you to conveniently indicate a power net at any location in the design. Power nets of the same designator automatically connect throughout your design #portal #power
A generic fixed inductor for rapid developing circuit topology. *You can now change the footprint and 3D model at the top level anytime you want. This is the power of #generics
@copilot list all ICs and the decoupling capacitors attached to each.
Ensure to include all ICs present in the design, including digital ICs, power converters, LDOs, etc.
For every IC, clearly state:
What power net the decoupling capacitors are attached to. What is the stated voltage of that net.
The voltage rating and value of the attached decoupling capacitors.
Signal with the expression “[WARNING]” if any of the following conditions are met:
no decoupling capacitors are attached;
the voltage of the power net is higher than the voltage rating of the capacitor;
No voltage range was stated for the capacitor.
Give a separate “[WARNING]” for each condition. Signal with the expression “[OK]” if none of those conditions are met
This project is a WiFi-enabled door and window sensor using the ESP8684-WROOM-02C module from Espressif Systems. It includes a triple-color LED indicator, Reed switch for detection, a 3.3V Regulatory mechanism, and USB C for firmware flashing. It's powered by a regular non-rechargeable AAA battery.
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@copilot this is WiFi Door and Window Sensor. So basically this sensor you need ...
@copilot this is WiFi Door and Window Sensor. So basically this sensor you need to connect once and then it will wait for signal from REED1. How can I improve this device?
You've built a respectable Wi-Fi door and window sensor design using the ESP8684-WROOM-02C WiFi module. To improve your current design, consider the following suggestions:
Power Management: IoT devices are often battery powered and need to be energy efficient. Deep sleep mode could be leveraged during periods of inactivity to prolong battery life.
Tamper Detection: Adding a small tamper detection switch that sends an alert if the sensor is forcibly removed or destroyed could enhance the security.
Additional Sensor Integration: Consider expanding the functionality of your device by adding other sensors such as temperature, humidity, light sensors, etc.
OTA Updates: Enable Over-The-Air (OTA) updates to keep the firmware of your device up-to-date without physically connecting it to the programmer.
Enclosure Design: Ensure your device is enclosed well, especially if it is meant for outdoor placement. The design needs to be waterproof and robust to withstand outside conditions.
Connectivity Check: Enabling connectivity check can be useful. The device can alert the user if it's disconnected from Wi-Fi for a prolonged period.
Signal Strength Indicator: A WiFi signal strength indicator could help users during the installation process to find best place for connectivity.
Please review this suggestions and let me know your thoughts before proceeding with potential design changes.
1y
@copilot what resistors values do I need for each color of LTST-C19HE1WT RGB LED...
The brightness of an LED (Light Emitting Diode) is determined by the current flowing through it. The LED's datasheet should provide a forward current for each color and a forward voltage drop.
The LTST-C19HE1WT is a tri-color RGB LED. According to its datasheet, the typical forward voltages at 20mA are:
Red: $2.0V$
Green: $3.2V$
Blue: $3.2V$
Assuming we run the LED from a $3.3V$ supply, we can use these forward voltages to calculate individual resistor values using Ohm's Law:
To calculate the resistor values at a forward current of $10mA (0.01A)$, we can use the same forward voltage values from the datasheet and the same formula. Here are the calculated values:
For Red LED: $R_{Red} = \frac{{3.3V - 2.0V}}{{0.01A}} = 130\Omega$
For Green LED: $R_{Green} = \frac{{3.3V - 3.2V}}{{0.01A}} = 10\Omega$
For Blue LED: $R_{Blue} = \frac{{3.3V - 3.2V}}{{0.01A}} = 10\Omega$
These are the theoretical resistor values. For implementation, the following standard resistor values could be used:
A standard value of $130\Omega$ resistor can be used for the Red LED.
A standard value of $10\Omega$ resistor can be used for both Green and Blue LEDs.
Please note that halving the current will lead to a less bright output, but it also cuts the power used by each LED in half. This could be advantageous in low-power applications or to extend battery life.
I apologize for any confusion earlier. Let's use the updated forward voltages you provided to calculate the resistor values. At $10mA (0.01A)$ forward current, the resistor values are:
For Red LED: $R_{Red} = \frac{{3.3V - 1.95V}}{{0.01A}} = 135\Omega$
For Green LED: $R_{Green} = \frac{{3.3V - 2.8V}}{{0.01A}} = 50\Omega$
For Blue LED: $R_{Blue} = \frac{{3.3V - 2.8V}}{{0.01A}} = 50\Omega$
These are theoretical values and would need to be rounded to the nearest standard resistor values. The closest standard 5% (E24 series) resistor values are:
For Red LED, you can use a $130\Omega$ or $150\Omega$ resistor.
For both Green and Blue LEDs, a $51\Omega$ resistor is the closest standard value.
Remember, these calculations are made under the assumption that the LED brightness is proportional to the forward current and the supplied voltage is at a fixed $3.3V$. Also, these values can vary between batches of LEDs due to manufacturing tolerances.
1y
@copilot I need to minimize power consumption of this circuit. What max value fo...
The max value of pull-up resistor R7 connected to the EN (Enable) pin of the ESP8684-WROOM-02C module will largely depend on two factors:
The minimum current required to reliably read a logical high on the input pin (which in the most cases can be taken from the datasheet of the ESP8684).
The high-level input voltage, $V_{IH}$, for the EN pin which is typically a percentage of the supply voltage $V_{CC}$, specified in the module's datasheet.
Unfortunately, without the datasheet values we cannot calculate the exact maximum resistor value, but as a basic approximation:
If we are using a 3.3V system, a typical pull-up resistor can range from 1k to 10k ohms.
Some power optimized designs might use higher values up to 100k or even 1M ohms.
So, to choose the right value for the resistor, you would need to check the datasheet of ESP5684-WROOM-02C to know the recommended standard values, then try to increase the resistance value slowly while ensuring that the system is still functioning properly.
On the other hand, it is important to note that the pull-up resistor will consume power only when the switch is closed (i.e., when the button is pressed), because it essentially forms part of a voltage divider. When the switch is open, theoretically, no current is being consumed over the resistor since there's no path to ground. However, in practical applications, to reduce overall power consumption, you can:
Put your microcontrollers like the ESP8684 in sleep mode when they're not performing any processes.
Reduce duty cycles of any PWM signals.
Use components that have sleep mode or low power mode.
Remember to double check your design and perform tests while making these modifications.
Unfortunately, you may need to manually check the specific details in your datasheet based on the following guidelines:
Search for the "Electrical Characteristics" table in the datasheet, where you can find a specific parameter called "Input High Voltage (VIH)" or similar for the GPIOs.
Next, search for a parameter labelled "Input Leakage Current", or similar (I_IL), in the same table or if not there, look for it in another section usually called "Absolute Maximum Ratings" or "DC Specifications".
Here are two essential considerations:
The resulting resistance value combined with any internal resistance should fall within the parameters labelled "Pull-up/Pull-down resistance" (R_PULL) or similar parameters.
When running, ensure that the voltage at the pin doesn't drop below the "Input High Voltage" (V_IH) and doesn't exceed "VCC + 0.3V".
You can calculate the resistor using the formula below:
$R = \frac{V_{CC} - V_{IH}}{I_{IL}}$
Ensure that you cross-verify your calculations with your datasheet to confirm that your selected value does not exceed those parameters. Remember to keep some margin in your calculations for extra safety.
1y
Hey, I’m Copilot, your AI design assistant. I can help you brainstorm ideas, deb...
Hey, I’m Copilot, your AI design assistant. I can help you brainstorm ideas, debug problems, research components, and even make wiring connections for you. Ask me questions like:
@copilot I'm designing a PCB for a medical device that measures heart rate and temperature. Can you give me the list of components I will need?
@copilot How would I connect these parts to make the LED flash at 1kHz?
@copilot can you choose 4 digital pins on the ATMega328P-AU that I have here to use as GPIO given that I am already using some pins for reset, the external clock, UART, and I2C.
Chat with me by tagging @copilot on comments or in the chat.
1y
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Passive Components
Resistor Power Rating
Beta
Checks that the power traveling across a given resistor is under its rating with 50% headroom.
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