▲ 1 r/smartwatch
Where would one go to buy a good cheap smartwatch screen?
What kind of connectors would be used to attach screen to a pcb?
u/Objective-Local7164 — 21 hours ago
u/Objective-Local7164
r/AskElectronics r/rfelectronics r/smartwatch r/3dprinter r/3DPrintingCirclejerk r/ElectricalEngineering r/shittyaskelectronics r/PCB
Will this 3.0V battery undervoltage protection circuit work how I am thinking it will?
XC6120C This is the IC I am planning on using for this.
DMT6009LK3-13 This is the external FET I am planning on using for this.
I want to use this to set a 3V threshold so when my battery drops below 3V it turns off the external FET and shuts off the circuit.
My source will be a 3.7V li-ion coin cell battery providing DC power. The AC in my Falstad sim is to simulate the function of the circuit.
Am I doing this right and is there something I am missing or should be aware of? Thanks for your time.
u/Objective-Local7164 — 1 day ago
Asking for a friend…
What is a safe voltage to use for rectal stimulation?
u/Objective-Local7164 — 7 days ago
When im powering NRF with USB, Voltage will be applied to my LDO output. How do I do this without breaking the LDO?
u/Objective-Local7164 — 8 days ago
▲ 1 r/PCB
Im thinking about getting the Centauri Carbon 2 for 3D printing enclosures for my pcbs. Any advice?
reddit.comu/Objective-Local7164 — 12 days ago
▲ 3 r/AskElectronics
Im thinking about getting the Centauri Carbon 2 for 3D printing enclosures for my pcbs. Any advice?
reddit.comu/Objective-Local7164 — 12 days ago
▲ 0 r/3dprinter
Im getting my first 3D printer. My budget is around 400$. Any recommendations and things I should consider?
I will be using the printer to make cases for my printed circuit boards. Heart rate monitor casing, digital watch type casing, small electronic device custom casings. I need it to be at least a nice sturdy plastic that can survive being dropped on the floor without breaking. I dont need crazy detailed accuracy, just a decent amount of customization.
I dont care about how long it takes to print. I care about reliability and consistent performance over time. I appreciate any advice anyone has to give. Thanks.
So far I am looking at the Centauri carbon 2.
u/Objective-Local7164 — 12 days ago
Im getting my first 3D printer. My budget is around 400$. Any recommendations and things I should consider?
I will be using the printer to make cases for my printed circuit boards. Heart rate monitor casing, digital watch type casing, small electronic device custom casings. I need it to be at least a nice sturdy plastic that can survive being dropped on the floor without breaking. I dont need crazy detailed accuracy, just a decent amount of customization.
I dont care about how long it takes to print. I care about reliability and consistent performance over time. I appreciate any advice anyone has to give. Thanks.
So far I am looking at the Centauri carbon 2.
u/Objective-Local7164 — 12 days ago
Which rf capable MCU do you think is the best for small wearables?
NRF52840 vs NRF52832 vs STM32WB15
I have seen the 52832 in multiple designs and it seems like the no brainer / go to mcu for small wearables but I cant tell among these 3, which one I should go with.
My application would be coin cell battery powered small EKG, EMG, Pulse Oximeter small wearble bio
u/Objective-Local7164 — 14 days ago
▲ 2 r/AskElectronics
Which rf capable MCU do you think is the best for small wearables?
NRF52840 vs NRF52832 vs STM32WB15
I have seen the 52832 in multiple designs and it seems like the no brainer / go to mcu for small wearables but I cant tell among these 3, which one I should go with.
My application would be coin cell battery powered small EKG, EMG, Pulse Oximeter small wearble bio signal devices that require low sample rates and just 1 adc, either uart or spi, and BLE bluetooth low energy on the lowest transmit power setting.
u/Objective-Local7164 — 14 days ago
▲ 37 r/rfelectronics
This RF switch datasheet recommends 22pF DC blocking caps in series with every RF line. Why not a bigger value?
RF switch datasheet = SKY13575-639LF
Now.. I know that 22pF with a 50ohm load has a cutoff that is not near the 2.4ghz but I am curious why not 100pF or 500pF?
Also what kind of caps should I use? I am thinking NPO precision 1% ceramic caps with a package size that closest matches my trace width.
u/Objective-Local7164 — 15 days ago
What are some very low power MCU's that are good for PWM?
I just need the mcu to have a couple different pins that output different pwm signals. 100us on 20ms off. 50us on 20ms off. are pretty much around what i will be needing.
u/Objective-Local7164 — 17 days ago
What are some very low power MCU's that are good for PWM?
I just need the mcu to have a couple different pins that output different pwm signals. 100us on 20ms off. 50us on 20ms off. are pretty much around what i will be needing.
u/Objective-Local7164 — 17 days ago
▲ 6 r/AskElectronics
What are some very low power MCU's that are good for PWM?
I just need the mcu to have a couple different pins that output different pwm signals. 50us on 20ms off. are pretty much around what i will be needing.
u/Objective-Local7164 — 17 days ago
What kind of potential problems should I be aware of when using ICL thermistors?
Im thinking about using something like this to stop the initial inrush current when I turn on my boost converter circuit.
u/Objective-Local7164 — 20 days ago
Is there anything wrong with my Hbridge / Gate driver circuit?
Gate Driver = IRS2301STRPBF
NMOS = IRF640NPBF
MCU = ESP32-C6-MINI-1-N4
Diode = ES1D
Switching Speed = 100us on time, 10 to 20ms off time for each side with 1ms deadtime.
The jumpers in the middle of the Hbridge are for experimentation of different loads after PCB is manufactured.
u/Objective-Local7164 — 21 days ago
I dont understand how this equation is supposed to give the Fets gate capacitance?
This is from Bootstrap Circuitry Selection by texas instruments. Following the logic of this question, if you changed vdd you would change the fets gate capacitance which does not make sense to me. What am I not understanding about this?
u/Objective-Local7164 — 21 days ago
▲ 1 r/AskElectronics
If I am driving a gate of a PMOS that already has 100V on it, will the gate driver be able to drive it to 90V with a 10V output or will it break?
Accoring to the datasheet, HO can have a Voltage of VB + 0.3 and VB can be 625V max so would that mean 1. Having 100V on HO will not be a problem and 2. If HO is driving the gate with 10V will it just make the 100V line 90V?
What could go wrong here?
IR2101 datasheet typical connection
The Area circled in red will be replaced by the gate driver, specifically the HO pin.
In the IR2101 datasheet it stated that the max V that can be on the HO pin is VB + 0.3. Would that mean that my 100V would be no problem on the HO Pin?
u/Objective-Local7164 — 22 days ago
If I am driving a gate of a PMOS that already has 100V on it, will the gate driver be able to drive it to 90V with a 10V output or will it break?
Accoring to the datasheet, HO can have a Voltage of VB + 0.3 and VB can be 625V max so would that mean 1. Having 100V on HO will not be a problem and 2. If HO is driving the gate with 10V will it just make the 100V line 90V?
What could go wrong here?
IR2101 datasheet typical connection
The Area circled in red will be replaced by the gate driver, specifically the HO pin.
In the IR2101 datasheet it stated that the max V that can be on the HO pin is VB + 0.3. Would that mean that my 100V would be no problem on the HO Pin?
u/Objective-Local7164 — 22 days ago