#pwm — Public Fediverse posts
Live and recent posts from across the Fediverse tagged #pwm, aggregated by home.social.
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#IHopeJohnRoberts falls into a pleasant sleep in his surprisingly comfy Greyhound bus seat, finally just letting all his anxieties fall away for a blissful while, and so doesn't notice that his bus to Portland isn't passing through Baltimore and Wilmington and then New York, but rather Frederick and Cumberland and Morgantown. #PWM #PDX
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#IHopeJohnRoberts falls into a pleasant sleep in his surprisingly comfy Greyhound bus seat, finally just letting all his anxieties fall away for a blissful while, and so doesn't notice that his bus to Portland isn't passing through Baltimore and Wilmington and then New York, but rather Frederick and Cumberland and Morgantown. #PWM #PDX
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#IHopeJohnRoberts falls into a pleasant sleep in his surprisingly comfy Greyhound bus seat, finally just letting all his anxieties fall away for a blissful while, and so doesn't notice that his bus to Portland isn't passing through Baltimore and Wilmington and then New York, but rather Frederick and Cumberland and Morgantown. #PWM #PDX
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#IHopeJohnRoberts falls into a pleasant sleep in his surprisingly comfy Greyhound bus seat, finally just letting all his anxieties fall away for a blissful while, and so doesn't notice that his bus to Portland isn't passing through Baltimore and Wilmington and then New York, but rather Frederick and Cumberland and Morgantown. #PWM #PDX
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#IHopeJohnRoberts falls into a pleasant sleep in his surprisingly comfy Greyhound bus seat, finally just letting all his anxieties fall away for a blissful while, and so doesn't notice that his bus to Portland isn't passing through Baltimore and Wilmington and then New York, but rather Frederick and Cumberland and Morgantown. #PWM #PDX
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https://www.europesays.com/ie/?p=527092 Poco X8 Pro Max: Can an invisible display technology strain your eyes? #AMOLED #benchmarks #brightness #display #dithering #Dolby #Éire #eyestrain #fatigue #flicker #FRC #GraphicsCard #HDR10 #headaches #IE #Ireland #laptop #Mobile #netbook #notebook #Poco #processor #PWM #refresh #reports #Review #Reviews #Smartphone #subpixels #Technology #test #tests #xiaomi
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Dimmable Desk Lamp Market in the United Kingdom | Report – IndexBox
United Kingdom Dimmable D…
#NewsBeep #News #UnitedKingdom #Accentlightingforhomedecor #consumergoodsmarketreport #Creatingambientworkspacelighting #dimmabledesklamp #forecast #GB #GreatBritain #LEDlightingmodules #market-analysis #PWM/ConstantCurrentDimmingCircuits #Reducingeyestrainduringscreenuse #Tasklightingforreading/writing #Touch/ButtonControlInterfaces #UK #Wi-Fi/BluetoothConnectivity
https://www.newsbeep.com/uk/592808/ -
FAKE- or Pseudo PWM - STM32 Bare Metal #9 In this video we will cover handling external interrupts using nothing but bare metal. #STM32 #BareMetal #Tutorial #Timer #PWM #STM32World #CurrentMakers #Streamline www.youtube.com/watch?v=VN7F...
FAKE- or Pseudo PWM - STM32 Ba... -
FAKE- or Pseudo PWM - STM32 Bare Metal #9
In this video we will cover handling external interrupts using nothing but bare metal.
#STM32 #BareMetal #Tutorial #Timer #PWM #STM32World #CurrentMakers #Streamline
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FAKE- or Pseudo PWM - STM32 Bare Metal #9
In this video we will cover handling external interrupts using nothing but bare metal.
#STM32 #BareMetal #Tutorial #Timer #PWM #STM32World #CurrentMakers #Streamline
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FAKE- or Pseudo PWM - STM32 Bare Metal #9
In this video we will cover handling external interrupts using nothing but bare metal.
#STM32 #BareMetal #Tutorial #Timer #PWM #STM32World #CurrentMakers #Streamline
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Управление фазой аппаратного PWM сигнала на STM32
На микроконтроллерах STM32 можно генерировать аппаратные PWM сигналы. Это всегда применяют для регулирования яркости свечения, управления температурой нагревателей, управления крутящим моментом на моторах. При этом легко можно регулировать частоту, заполнение и инвертировать фазу меняя полярность. Однако как непрерывно регулировать фазу PWM?. В этом тексте я написал три способа управлять фазой PWM сигнала.
https://habr.com/ru/articles/1023940/
#pwm #stm32 #phase #pwm_phase #hw_pwm #pwm_hw #шим #masterslave #master #slave
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Управление фазой аппаратного PWM сигнала на STM32
На микроконтроллерах STM32 можно генерировать аппаратные PWM сигналы. Это всегда применяют для регулирования яркости свечения, управления температурой нагревателей, управления крутящим моментом на моторах. При этом легко можно регулировать частоту, заполнение и инвертировать фазу меняя полярность. Однако как непрерывно регулировать фазу PWM?. В этом тексте я написал три способа управлять фазой PWM сигнала.
https://habr.com/ru/articles/1023940/
#pwm #stm32 #phase #pwm_phase #hw_pwm #pwm_hw #шим #masterslave #master #slave
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Управление фазой аппаратного PWM сигнала на STM32
На микроконтроллерах STM32 можно генерировать аппаратные PWM сигналы. Это всегда применяют для регулирования яркости свечения, управления температурой нагревателей, управления крутящим моментом на моторах. При этом легко можно регулировать частоту, заполнение и инвертировать фазу меняя полярность. Однако как непрерывно регулировать фазу PWM?. В этом тексте я написал три способа управлять фазой PWM сигнала.
https://habr.com/ru/articles/1023940/
#pwm #stm32 #phase #pwm_phase #hw_pwm #pwm_hw #шим #masterslave #master #slave
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I will absolutely hate soldering this, but it will provide 15 PWM channels with MOSFETs able to switch 12V/1A each - so enough to power and control 5 LED RGB strips of at least 1m length with a resolution of 10 bit on each channel; the ProMicro nRF52840 will provide control and BLE, and a PCA9865 will take care of the PWM stuff (using those instead of the MCU PWM makes interfacing and enhancing the platform easier - I figure).
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Polémica con el Galaxy S26 Ultra – Su función estrella «Privacy Display» está provocando fatiga ocular y dolores de cabeza
Lo que debía ser la innovación más aplaudida de Samsung para 2026 se está convirtiendo en su mayor dolor de cabeza, literalmente. A pocos días del lanzamiento oficial, una oleada de usuarios del Galaxy S26 Ultra ha comenzado a reportar fatiga ocular, náuseas y cefaleas tras usar el dispositivo. El culpable parece ser el nuevo panel «Privacy Display», una tecnología diseñada para ocultar el contenido de la pantalla a los curiosos, pero que está pasando factura a los ojos más sensibles (Fuente AndroidAuthority).
Esta controversia, se suma a una semana difícil para Samsung tras el error de certificación de Google Play que bloqueó apps bancarias en algunas unidades del S26.
El problema: PWM de baja frecuencia y «texto borroso»
Aunque Samsung promocionó el S26 Ultra como la cima de la ingeniería visual, los entusiastas de la tecnología han descubierto que la compañía sigue utilizando una frecuencia de PWM (modulación por ancho de pulsos) de solo 480Hz, muy por debajo de los estándares de salud ocular que ya ofrecen sus competidores chinos como Vivo u Oppo.
- Parpadeo invisible: Los usuarios sensibles al parpadeo de las pantallas OLED experimentan mareos similares a los de las gafas de VR, ya que el cerebro detecta el ciclo de encendido y apagado de los píxeles aunque el ojo no lo vea.
- Falta de nitidez: Se han viralizado fotos macro que comparan el S26 Ultra con el S25 Ultra, mostrando que el texto en el nuevo modelo parece «sucio» o difuminado. Esto se debe a la Black Matrix, la estructura física necesaria para que funcione el filtro de privacidad, que reduce la claridad de los bordes de las letras.
¿Es un fallo de hardware o de software?
Lo más preocupante para los compradores es que estas molestias ocurren incluso con la función de Privacy Display desactivada.
«Es como si estuvieras mirando la pantalla a través de una lente empañada», comentan usuarios en Reddit.
Dado que la capa de privacidad es una característica física del panel OLED, expertos como el filtrador Ice Universe sugieren que una actualización de software no podrá corregirlo por completo, aunque Samsung podría intentar mitigar el efecto aumentando el brillo artificialmente mediante un parche.
Confusión con los «10 bits»
Para empeorar las cosas, Samsung ha tenido que rectificar sus materiales de marketing. Aunque inicialmente se dijo que el S26 Ultra tenía un panel nativo de 10 bits (1.000 millones de colores), la empresa ha confirmado que se trata de un panel de 8 bits con FRC (una técnica que hace parpadear los píxeles para simular más colores). Este parpadeo adicional, sumado al bajo PWM, es la combinación perfecta para generar fatiga visual en sesiones largas.
La respuesta de Samsung
Ante la presión, Samsung ha declarado que está investigando los reportes, pero mantiene que la pantalla cumple con todos los estándares de seguridad vigentes. Mientras tanto, recomiendan a los usuarios activar el «Escudo de comodidad ocular» y evitar niveles de brillo extremadamente bajos en habitaciones oscuras.
Este «Display-gate» ocurre en un marzo de 2026 donde la industria está bajo la lupa: mientras Apple filtra su iPhone plegable sin pliegues, Samsung se enfrenta a críticas por una pantalla que, por intentar proteger la privacidad del usuario, ha terminado comprometiendo su bienestar.
#android #arielmcorg #ciberseguridad #DisplayGate #GalaxyS26Ultra #infosertec #innovación #pantalla #PORTADA #PWM #salud #Samsung #TechNews2026 #tecnología -
Micro Music Media Library (2019)
by @protodome
"This is the companion web page for the Micro Music: Exploring the Idiosyncratic Compositional Strategies Encountered in 1-Bit, Limited Memory Environments doctoral project. [...] 1-bit music, generally considered a sub-division of chiptune, is the music of a single square wave. [...] [T]he unique techniques and auditory tricks of contemporary 1-bit practice exploit the limits of human perception. Through layers of modulation, abstraction and clever writing, these compositional methods generate music far more complex than the medium would, at first impressions, indicate..."
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Micro Music Media Library (2019)
by @protodome
"This is the companion web page for the Micro Music: Exploring the Idiosyncratic Compositional Strategies Encountered in 1-Bit, Limited Memory Environments doctoral project. [...] 1-bit music, generally considered a sub-division of chiptune, is the music of a single square wave. [...] [T]he unique techniques and auditory tricks of contemporary 1-bit practice exploit the limits of human perception. Through layers of modulation, abstraction and clever writing, these compositional methods generate music far more complex than the medium would, at first impressions, indicate..."
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Micro Music Media Library (2019)
by @protodome
"This is the companion web page for the Micro Music: Exploring the Idiosyncratic Compositional Strategies Encountered in 1-Bit, Limited Memory Environments doctoral project. [...] 1-bit music, generally considered a sub-division of chiptune, is the music of a single square wave. [...] [T]he unique techniques and auditory tricks of contemporary 1-bit practice exploit the limits of human perception. Through layers of modulation, abstraction and clever writing, these compositional methods generate music far more complex than the medium would, at first impressions, indicate..."
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Micro Music Media Library (2019)
by @protodome
"This is the companion web page for the Micro Music: Exploring the Idiosyncratic Compositional Strategies Encountered in 1-Bit, Limited Memory Environments doctoral project. [...] 1-bit music, generally considered a sub-division of chiptune, is the music of a single square wave. [...] [T]he unique techniques and auditory tricks of contemporary 1-bit practice exploit the limits of human perception. Through layers of modulation, abstraction and clever writing, these compositional methods generate music far more complex than the medium would, at first impressions, indicate..."
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Micro Music Media Library (2019)
by @protodome
"This is the companion web page for the Micro Music: Exploring the Idiosyncratic Compositional Strategies Encountered in 1-Bit, Limited Memory Environments doctoral project. [...] 1-bit music, generally considered a sub-division of chiptune, is the music of a single square wave. [...] [T]he unique techniques and auditory tricks of contemporary 1-bit practice exploit the limits of human perception. Through layers of modulation, abstraction and clever writing, these compositional methods generate music far more complex than the medium would, at first impressions, indicate..."
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https://www.europesays.com/ie/295618/ Honor Magic8 Pro: No smartphone offers such comprehensive eye protection #Android #Augenkomfort #Augenschutz #benchmarks #Blaulichtfilter #Circadian #Darkmode #display #Éire #GraphicsCard #Honor #IE #Ireland #laptop #Magic8 #Magic8Pro #Mobile #netbook #notebook #OLED #processor #PWM #reports #Review #Reviews #Smartphones #Technology #test #tests #TÜVRheinland #zirkularpolarisiert
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https://www.europesays.com/pl/118123/ Chieftec The Cube – tania obudowa mATX jak głośnik, która oferuje składaną konstrukcję i 200 mm wentylator. Specyfikacja i cena #chieftec #ChieftecTheCube #hdb #matx #microatx #MiniITX #Nauka #NaukaITechnika #NaukaTechnika #obudowa #PL #Poland #Polish #Polska #Polski #PWM #Science #ScienceAndTechnology #ScienceTechnology #specyfikacja #Technika #Technology
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The most literal LED lighting dimmer switch in the known universe. #pwm
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The most literal LED lighting dimmer switch in the known universe. #pwm
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The most literal LED lighting dimmer switch in the known universe. #pwm
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The most literal LED lighting dimmer switch in the known universe. #pwm
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https://www.europesays.com/ie/171781/ Goldman Sachs says we’re not in an AI bubble, and its young multimillionaire clientele are all-in on AI-energy investments and healthcare innovations #AffluentClients #attendees #BoalsMoeller #BrittanyBoalsMoeller #DarioAmodei #Éire #GoldmanSachs #Health #HealthCare #Healthcare #IE #Ireland #MarkZuckerberg #MindyKaling #PWM #SahilBloom #WealthyClientele
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Обзор микросхемы DRV8870
DRV8870 - это старая простая микросхема управления коллекторным DC -мотором с токами в обмотках до 3.5 Ампер от компании Texas Instruments. По сути это драйвер H-моста . Причем H-мост встроен прямо внутрь корпуса самой микросхемы. Это полностью интегрированное решение. В этом тексте я произвел обзор микросхемы DRV8870. Посмотрим с какой стороны следует подходить к микросхеме DRV8870.
https://habr.com/ru/articles/952484/
#DRV8870 #hbridge #hмост #stm32 #DevEBoxSTM32F4XX_M_V30 #STM32F407VGT6 #pwm #TIMER #gpio #18650
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Обзор микросхемы DRV8870
DRV8870 - это старая простая микросхема управления коллекторным DC -мотором с токами в обмотках до 3.5 Ампер от компании Texas Instruments. По сути это драйвер H-моста . Причем H-мост встроен прямо внутрь корпуса самой микросхемы. Это полностью интегрированное решение. В этом тексте я произвел обзор микросхемы DRV8870. Посмотрим с какой стороны следует подходить к микросхеме DRV8870.
https://habr.com/ru/articles/952484/
#DRV8870 #hbridge #hмост #stm32 #DevEBoxSTM32F4XX_M_V30 #STM32F407VGT6 #pwm #TIMER #gpio #18650
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Обзор микросхемы DRV8870
DRV8870 - это старая простая микросхема управления коллекторным DC -мотором с токами в обмотках до 3.5 Ампер от компании Texas Instruments. По сути это драйвер H-моста . Причем H-мост встроен прямо внутрь корпуса самой микросхемы. Это полностью интегрированное решение. В этом тексте я произвел обзор микросхемы DRV8870. Посмотрим с какой стороны следует подходить к микросхеме DRV8870.
https://habr.com/ru/articles/952484/
#DRV8870 #hbridge #hмост #stm32 #DevEBoxSTM32F4XX_M_V30 #STM32F407VGT6 #pwm #TIMER #gpio #18650
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Simple PWM Filter PCB Build Guide
Here are the build notes for my Simple PWM Filter PCB Design. Below you can see it connected to my Pico Touch Board.
Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments!
If you are new to electronics and microcontrollers, see the Getting Started pages.
Bill of Materials
- PWM Audio Filter PCB (GitHub link below)
- 2x Suitable filter components, for example, per channel:
- 3x 1KΩ resistors
- 2x 100nF ceramic capacitor
- 1x 2u2 electrolytic capacitor
- Optional: Pin headers
- Optional: 2x 3.5mm TRS sockets (pcb mounted, see photos for footprint)
Build Steps
Taking a typical “low to high” soldering approach, this is the suggested order of assembly:
- All resistors.
- TRS sockets (if used).
- Disc capacitors.
- 3-way jumper headers (if used).
- Electrolytic capacitors.
Here are some build photos.
If the electrolytic capacitors will be bent over, then they should be bent and soldered in place before the header pins.
Testing
I recommend performing the general tests described here: PCBs.
PCB Errata
There are no known issues with this PCB at present.
Enhancements:
- As previously mentioned it might have been useful to label the left and right channels and use the alternative resistor circuit symbol.
- It might have been useful to include solder jumpers to allow the simple combining of the left and right inputs and outputs
- Some additional connection points for an oscilloscope might have been useful too.
Sample Applications
Here are some applications to get started with:
- Pico Touch Board Audio – 3x 1K resistors, 3x 100nF capacitors, and 1x 2u2 electrolytic per channel.
Experimenter board
Rather than fixed components, it is possible to solder on round pin header sockets to allow components to be pushed into place. This means that it is fairly easy to experiment with alternative component values to see what difference they make.
When doing this, I only soldered up one channel, but joined the left/right inputs and outputs by adding a solder bridge across the pin headers. I also soldered additional pins to the spare GND connections from the second channel. This allows plenty of pin connections for an oscilloscope.
The connections for components aren’t as tight as they could be, especially for low-wattage components with pretty thin legs.
It might be that just continuing to use solderless breadboard for experiments is simpler, but it was pretty useful to be able to leave oscilloscope connections and the input and output connected whilst experimenting.
Board Manufacturing
These boards are sized to allow them to be ordered in a 2×4 panel if required, and still remain within a 100x100mm footprint. I used jlcpcb’s panel options with v-cuts and it was really quite inexpensive to do.
Closing Thoughts
I’m still not sure I really understand enough analog electronics to get the theory of how a dual-stage filter incorporating a potential divider still works, and any simulation is still not quite matching my theory to experiment.
As has been said, “in theory, theory and practice are the same, in practice they are different”.
This might make some proper practicing a bit easier.
Kevin
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Simple PWM Filter PCB Build Guide
Here are the build notes for my Simple PWM Filter PCB Design. Below you can see it connected to my Pico Touch Board.
Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments!
If you are new to electronics and microcontrollers, see the Getting Started pages.
Bill of Materials
- PWM Audio Filter PCB (GitHub link below)
- 2x Suitable filter components, for example, per channel:
- 3x 1KΩ resistors
- 2x 100nF ceramic capacitor
- 1x 2u2 electrolytic capacitor
- Optional: Pin headers
- Optional: 2x 3.5mm TRS sockets (pcb mounted, see photos for footprint)
Build Steps
Taking a typical “low to high” soldering approach, this is the suggested order of assembly:
- All resistors.
- TRS sockets (if used).
- Disc capacitors.
- 3-way jumper headers (if used).
- Electrolytic capacitors.
Here are some build photos.
If the electrolytic capacitors will be bent over, then they should be bent and soldered in place before the header pins.
Testing
I recommend performing the general tests described here: PCBs.
PCB Errata
There are no known issues with this PCB at present.
Enhancements:
- As previously mentioned it might have been useful to label the left and right channels and use the alternative resistor circuit symbol.
- It might have been useful to include solder jumpers to allow the simple combining of the left and right inputs and outputs
- Some additional connection points for an oscilloscope might have been useful too.
Sample Applications
Here are some applications to get started with:
- Pico Touch Board Audio – 3x 1K resistors, 3x 100nF capacitors, and 1x 2u2 electrolytic per channel.
Experimenter board
Rather than fixed components, it is possible to solder on round pin header sockets to allow components to be pushed into place. This means that it is fairly easy to experiment with alternative component values to see what difference they make.
When doing this, I only soldered up one channel, but joined the left/right inputs and outputs by adding a solder bridge across the pin headers. I also soldered additional pins to the spare GND connections from the second channel. This allows plenty of pin connections for an oscilloscope.
The connections for components aren’t as tight as they could be, especially for low-wattage components with pretty thin legs.
It might be that just continuing to use solderless breadboard for experiments is simpler, but it was pretty useful to be able to leave oscilloscope connections and the input and output connected whilst experimenting.
Board Manufacturing
These boards are sized to allow them to be ordered in a 2×4 panel if required, and still remain within a 100x100mm footprint. I used jlcpcb’s panel options with v-cuts and it was really quite inexpensive to do.
Closing Thoughts
I’m still not sure I really understand enough analog electronics to get the theory of how a dual-stage filter incorporating a potential divider still works, and any simulation is still not quite matching my theory to experiment.
As has been said, “in theory, theory and practice are the same, in practice they are different”.
This might make some proper practicing a bit easier.
Kevin
-
Simple PWM Filter PCB Build Guide
Here are the build notes for my Simple PWM Filter PCB Design. Below you can see it connected to my Pico Touch Board.
Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments!
If you are new to electronics and microcontrollers, see the Getting Started pages.
Bill of Materials
- PWM Audio Filter PCB (GitHub link below)
- 2x Suitable filter components, for example, per channel:
- 3x 1KΩ resistors
- 2x 100nF ceramic capacitor
- 1x 2u2 electrolytic capacitor
- Optional: Pin headers
- Optional: 2x 3.5mm TRS sockets (pcb mounted, see photos for footprint)
Build Steps
Taking a typical “low to high” soldering approach, this is the suggested order of assembly:
- All resistors.
- TRS sockets (if used).
- Disc capacitors.
- 3-way jumper headers (if used).
- Electrolytic capacitors.
Here are some build photos.
If the electrolytic capacitors will be bent over, then they should be bent and soldered in place before the header pins.
Testing
I recommend performing the general tests described here: PCBs.
PCB Errata
There are no known issues with this PCB at present.
Enhancements:
- As previously mentioned it might have been useful to label the left and right channels and use the alternative resistor circuit symbol.
- It might have been useful to include solder jumpers to allow the simple combining of the left and right inputs and outputs
- Some additional connection points for an oscilloscope might have been useful too.
Sample Applications
Here are some applications to get started with:
- Pico Touch Board Audio – 3x 1K resistors, 3x 100nF capacitors, and 1x 2u2 electrolytic per channel.
Experimenter board
Rather than fixed components, it is possible to solder on round pin header sockets to allow components to be pushed into place. This means that it is fairly easy to experiment with alternative component values to see what difference they make.
When doing this, I only soldered up one channel, but joined the left/right inputs and outputs by adding a solder bridge across the pin headers. I also soldered additional pins to the spare GND connections from the second channel. This allows plenty of pin connections for an oscilloscope.
The connections for components aren’t as tight as they could be, especially for low-wattage components with pretty thin legs.
It might be that just continuing to use solderless breadboard for experiments is simpler, but it was pretty useful to be able to leave oscilloscope connections and the input and output connected whilst experimenting.
Board Manufacturing
These boards are sized to allow them to be ordered in a 2×4 panel if required, and still remain within a 100x100mm footprint. I used jlcpcb’s panel options with v-cuts and it was really quite inexpensive to do.
Closing Thoughts
I’m still not sure I really understand enough analog electronics to get the theory of how a dual-stage filter incorporating a potential divider still works, and any simulation is still not quite matching my theory to experiment.
As has been said, “in theory, theory and practice are the same, in practice they are different”.
This might make some proper practicing a bit easier.
Kevin
-
Simple PWM Filter PCB Build Guide
Here are the build notes for my Simple PWM Filter PCB Design. Below you can see it connected to my Pico Touch Board.
Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments!
If you are new to electronics and microcontrollers, see the Getting Started pages.
Bill of Materials
- PWM Audio Filter PCB (GitHub link below)
- 2x Suitable filter components, for example, per channel:
- 3x 1KΩ resistors
- 2x 100nF ceramic capacitor
- 1x 2u2 electrolytic capacitor
- Optional: Pin headers
- Optional: 2x 3.5mm TRS sockets (pcb mounted, see photos for footprint)
Build Steps
Taking a typical “low to high” soldering approach, this is the suggested order of assembly:
- All resistors.
- TRS sockets (if used).
- Disc capacitors.
- 3-way jumper headers (if used).
- Electrolytic capacitors.
Here are some build photos.
If the electrolytic capacitors will be bent over, then they should be bent and soldered in place before the header pins.
Testing
I recommend performing the general tests described here: PCBs.
PCB Errata
There are no known issues with this PCB at present.
Enhancements:
- As previously mentioned it might have been useful to label the left and right channels and use the alternative resistor circuit symbol.
- It might have been useful to include solder jumpers to allow the simple combining of the left and right inputs and outputs
- Some additional connection points for an oscilloscope might have been useful too.
Sample Applications
Here are some applications to get started with:
- Pico Touch Board Audio – 3x 1K resistors, 3x 100nF capacitors, and 1x 2u2 electrolytic per channel.
Experimenter board
Rather than fixed components, it is possible to solder on round pin header sockets to allow components to be pushed into place. This means that it is fairly easy to experiment with alternative component values to see what difference they make.
When doing this, I only soldered up one channel, but joined the left/right inputs and outputs by adding a solder bridge across the pin headers. I also soldered additional pins to the spare GND connections from the second channel. This allows plenty of pin connections for an oscilloscope.
The connections for components aren’t as tight as they could be, especially for low-wattage components with pretty thin legs.
It might be that just continuing to use solderless breadboard for experiments is simpler, but it was pretty useful to be able to leave oscilloscope connections and the input and output connected whilst experimenting.
Board Manufacturing
These boards are sized to allow them to be ordered in a 2×4 panel if required, and still remain within a 100x100mm footprint. I used jlcpcb’s panel options with v-cuts and it was really quite inexpensive to do.
Closing Thoughts
I’m still not sure I really understand enough analog electronics to get the theory of how a dual-stage filter incorporating a potential divider still works, and any simulation is still not quite matching my theory to experiment.
As has been said, “in theory, theory and practice are the same, in practice they are different”.
This might make some proper practicing a bit easier.
Kevin
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Simple PWM Filter PCB Build Guide
Here are the build notes for my Simple PWM Filter PCB Design. Below you can see it connected to my Pico Touch Board.
Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments!
If you are new to electronics and microcontrollers, see the Getting Started pages.
Bill of Materials
- PWM Audio Filter PCB (GitHub link below)
- 2x Suitable filter components, for example, per channel:
- 3x 1KΩ resistors
- 2x 100nF ceramic capacitor
- 1x 2u2 electrolytic capacitor
- Optional: Pin headers
- Optional: 2x 3.5mm TRS sockets (pcb mounted, see photos for footprint)
Build Steps
Taking a typical “low to high” soldering approach, this is the suggested order of assembly:
- All resistors.
- TRS sockets (if used).
- Disc capacitors.
- 3-way jumper headers (if used).
- Electrolytic capacitors.
Here are some build photos.
If the electrolytic capacitors will be bent over, then they should be bent and soldered in place before the header pins.
Testing
I recommend performing the general tests described here: PCBs.
PCB Errata
There are no known issues with this PCB at present.
Enhancements:
- As previously mentioned it might have been useful to label the left and right channels and use the alternative resistor circuit symbol.
- It might have been useful to include solder jumpers to allow the simple combining of the left and right inputs and outputs
- Some additional connection points for an oscilloscope might have been useful too.
Sample Applications
Here are some applications to get started with:
- Pico Touch Board Audio – 3x 1K resistors, 3x 100nF capacitors, and 1x 2u2 electrolytic per channel.
Experimenter board
Rather than fixed components, it is possible to solder on round pin header sockets to allow components to be pushed into place. This means that it is fairly easy to experiment with alternative component values to see what difference they make.
When doing this, I only soldered up one channel, but joined the left/right inputs and outputs by adding a solder bridge across the pin headers. I also soldered additional pins to the spare GND connections from the second channel. This allows plenty of pin connections for an oscilloscope.
The connections for components aren’t as tight as they could be, especially for low-wattage components with pretty thin legs.
It might be that just continuing to use solderless breadboard for experiments is simpler, but it was pretty useful to be able to leave oscilloscope connections and the input and output connected whilst experimenting.
Board Manufacturing
These boards are sized to allow them to be ordered in a 2×4 panel if required, and still remain within a 100x100mm footprint. I used jlcpcb’s panel options with v-cuts and it was really quite inexpensive to do.
Closing Thoughts
I’m still not sure I really understand enough analog electronics to get the theory of how a dual-stage filter incorporating a potential divider still works, and any simulation is still not quite matching my theory to experiment.
As has been said, “in theory, theory and practice are the same, in practice they are different”.
This might make some proper practicing a bit easier.
Kevin
-
Simple PWM Filter PCB Design
Having spent a bit of time attempting (although I’m not sure I’m succeeding yet) to understand how to get a useful filter for my Pico Touch Board Audio, I thought it would be useful to have a simple template PCB that could be used for a range of PWM low-pass filtering options.
This is my design.
Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments!
If you are new to electronics and microcontrollers, see the Getting Started pages.
The Circuit
This is following on from the discussion in Pico Touch Board Audio creating the template for a simple two-stage low-pass filter with an option for including a potential divider resistor to drop the overall voltage too.
I’ve doubled the circuit to allow for stereo in and out if required and have included both 3.5mm TRS sockets and pin jumper headers for both input and output.
It requires no power, being a completely passive filter.
If stereo is not required, then just one of the circuits can be populated – ideally the one connected to the TRS tip.
PCB Design
There isn’t much to this pcb layout really. I was particularly keen to keep the PCB away from specific values of components, so instead used the silkscreen to present a pseudo-circuit diagram to make it clear which components are which.
I’ve also tried to leave enough room for the electrolytic capacitors to allow them to be bent over if required.
Closing Thoughts
With hindsight, I can think of a couple of additions that would have been useful on the silkscreen – labelling which circuit is left and right for example.
And having the boards back, I should have added manual “wavy line” resistor diagrams rather than rectangles, but it is enough for what I need.
And it might have been useful to include some additional test points for connecting an oscilloscope.
Kevin
-
Simple PWM Filter PCB Design
Having spent a bit of time attempting (although I’m not sure I’m succeeding yet) to understand how to get a useful filter for my Pico Touch Board Audio, I thought it would be useful to have a simple template PCB that could be used for a range of PWM low-pass filtering options.
This is my design.
Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments!
If you are new to electronics and microcontrollers, see the Getting Started pages.
The Circuit
This is following on from the discussion in Pico Touch Board Audio creating the template for a simple two-stage low-pass filter with an option for including a potential divider resistor to drop the overall voltage too.
I’ve doubled the circuit to allow for stereo in and out if required and have included both 3.5mm TRS sockets and pin jumper headers for both input and output.
It requires no power, being a completely passive filter.
If stereo is not required, then just one of the circuits can be populated – ideally the one connected to the TRS tip.
PCB Design
There isn’t much to this pcb layout really. I was particularly keen to keep the PCB away from specific values of components, so instead used the silkscreen to present a pseudo-circuit diagram to make it clear which components are which.
I’ve also tried to leave enough room for the electrolytic capacitors to allow them to be bent over if required.
Closing Thoughts
With hindsight, I can think of a couple of additions that would have been useful on the silkscreen – labelling which circuit is left and right for example.
And having the boards back, I should have added manual “wavy line” resistor diagrams rather than rectangles, but it is enough for what I need.
And it might have been useful to include some additional test points for connecting an oscilloscope.
Kevin
-
Simple PWM Filter PCB Design
Having spent a bit of time attempting (although I’m not sure I’m succeeding yet) to understand how to get a useful filter for my Pico Touch Board Audio, I thought it would be useful to have a simple template PCB that could be used for a range of PWM low-pass filtering options.
This is my design.
Warning! I strongly recommend using old or second hand equipment for your experiments. I am not responsible for any damage to expensive instruments!
If you are new to electronics and microcontrollers, see the Getting Started pages.
The Circuit
This is following on from the discussion in Pico Touch Board Audio creating the template for a simple two-stage low-pass filter with an option for including a potential divider resistor to drop the overall voltage too.
I’ve doubled the circuit to allow for stereo in and out if required and have included both 3.5mm TRS sockets and pin jumper headers for both input and output.
It requires no power, being a completely passive filter.
If stereo is not required, then just one of the circuits can be populated – ideally the one connected to the TRS tip.
PCB Design
There isn’t much to this pcb layout really. I was particularly keen to keep the PCB away from specific values of components, so instead used the silkscreen to present a pseudo-circuit diagram to make it clear which components are which.
I’ve also tried to leave enough room for the electrolytic capacitors to allow them to be bent over if required.
Closing Thoughts
With hindsight, I can think of a couple of additions that would have been useful on the silkscreen – labelling which circuit is left and right for example.
And having the boards back, I should have added manual “wavy line” resistor diagrams rather than rectangles, but it is enough for what I need.
And it might have been useful to include some additional test points for connecting an oscilloscope.
Kevin
-
STM32 Tutorial #65 - Bit Banging PWM SUPER Optimized
In this Tutorial video we will dive further into timers by using a timer to bit bang PWM on a GPIO where no timer channel is available (such as PC13). We will begin by letting STM32CubeMX generate all the code but then optimize that by creating our own interrupt handler.
#STM32 #GettingStarted #Tutorial #STM32CubeIDE #STM32CubeMX #Timer #PWM #BitBang #STM32World
-
STM32 Tutorial #65 - Bit Banging PWM SUPER Optimized
In this Tutorial video we will dive further into timers by using a timer to bit bang PWM on a GPIO where no timer channel is available (such as PC13). We will begin by letting STM32CubeMX generate all the code but then optimize that by creating our own interrupt handler.
#STM32 #GettingStarted #Tutorial #STM32CubeIDE #STM32CubeMX #Timer #PWM #BitBang #STM32World
