electronic circuit

[ESP32] Modified circuit with power supply noise countermeasures to avoid surface mounting errors.

The MAX98357 itself needs to be connected to pins 25, 26 and 22 of the ESP32 WROOM 32E. keep the I2S signals (BCLK, LRCLK and DIN) as close as possible to pins 25 and 26 of the ESP32, as keeping the wires short reduces the risk of signal degradation and cross-talk. Attempt to optimise decoupling capacitors in the circuitry around the power supply to reduce power supply noise.

2024.09.05

built-in(C++)Development/Designelectronic circuitEntrepreneurMia

[ESP32] Investigation of the cause of cracked speaker sound and no playback due to wiring error (magnifying glass and oscilloscope)

When the IC package of the Class D amplifier was changed from TQFN to WLP, 4 out of 25 were defective in the speaker area as follows. Investigate the cause of sound crackling and audio not being played back. Verify if the sound crackling is resolved by first lowering the volume in the application. Next, using a magnifying glass, visually check for wiring defects.

2024.09.05

built-in(C++)Development/Designelectronic circuitEntrepreneurMia

[Stock issue] What if a part is out of stock when I place my order? Using JLCPCB’s pre-order.

In order to deal with out-of-stock issues like this one when they decide to order, JLCPCB allows pre-ordering, which means that the parts can be ordered before the PCB assembly is ordered and kept in stock at JLCPCB until the PCBA service is required. These pre-ordered parts are sent together with the PCB (and surface mount if you have also asked for surface mount), rather than separately from the PCB and only the parts are sent to you.

2024.08.21

Development/Designelectronic circuitEntrepreneurMia

[MAX98357A] Changed IC package of class D amplifier from TQFN to WLP

The MAX98357A series of ClassD audio amplifiers is available in TQFN and WLP packages. The WLP package is smaller and more cost-effective than the conventional TQFN package, as it does not require expensive through-hole vias (connection pins that pass through the PCB).

2023.12.28 2024.08.21

Development/Designelectronic circuit

[ESP32] Understanding the automatic boot loader mechanism and truth table

The automatic bootloader of the ESP32 is a function that enables automatic programme writing when the PC instructs the programmer to write the programme (by pressing the Upload button on PlatformIO) without having to manually press the EN or BOOT (IO0) pins.

2023.08.13 2024.08.02

Development/Designelectronic circuit

[Speaker] I attended the workshop on acrylic speaker amplifiers. I learned a lot.

I decided to start a speaker business for the hearing impaired in January this year, so this workshop came at the right time when I wanted to deepen my understanding around speakers.

2023.01.28 2024.08.01

Development/Designelectronic circuit

[ESP32] Implementation of Deep Sleep Mode and Timer Wake-Up Function

Introduction. Developing "Mia," a talking cat-shaped robot that speaks dialects. After releasing the beta version, sever...

2024.07.06

application(Flutter)built-in(C++)Development/Designelectronic circuit

[Electronic Circuit] Found defective products after 100 boards were installed and filed a Quality Complaint with JLCPCB.

The order was placed with JLCPCB for 100 boards, but in reality some of the pin headers were slightly out of level, resulting in LCD displays interfering with each other and not fitting together The JLCPCB order history section has a 'Quality Complaint' field where you can enter the nature of the fault and the number of faulty boards. and the number of defective boards.

2024.05.24 2024.06.08

Development/Designelectronic circuit

[JLCPCB] I received a confirmation email after ordering 100 boards. PCB operation is not checked

If there is no problem with the PCB layout, you will not receive an email from JLCPCB, so if you receive an email, it is when there is a problem, such as an incomplete circuit. Also, JLCPCB does not check the functionality of your own PCB, so you need to look at the schematic and PCB yourself to determine if the order is correct.

2024.05.08 2024.06.06

Development/Designelectronic circuit