Safety reminder: This article involves the charging interface and circuit modification of electronic products, which may pose safety hazards. The modification process is for reference only.

Many of the old devices in my house have micro USB charging ports. Even if I buy some electronic products (such as charging desk lights) now, many devices are still out of step with the times and still use micro USB charging ports. This makes me quite disgusted, but I cannot buy them.

As an obsessive-compulsive disorder, I can't wait to change all micro USB ports to type-c charging ports. After searching for a lot of information, I found that many people have tried, but most of the changes are not ideal, not perfect or universal.

After searching for more information, practicing multiple times, and improving, I have come up with a relatively general and simple modification plan, which can change the micro USB charging port of most devices to a type-C interface. This way, when buying electronic devices in the future, I won't worry because their charging port is too old.

I know that many people are very eager to update their old devices to type c charging ports, so I am writing this article to provide a detailed record of the modification process, hoping to be helpful to readers.

It should be noted in advance that this renovation plan only applies to the renovation of charging ports, such as Bluetooth earphones, speakers, controllers, wireless keyboards, wireless mice, charging desk lights, elderly phones, etc., but is not applicable to devices that require data transmission (such as old Android phones)

The QCY T1 Bluetooth earphone I bought three years ago was modified this time, and its charging port does not have the function of transmitting data, making it very suitable for modification.

Practical preparation tools:

Multimeter

Electric soldering iron, lead containing soldering tin, Jinji brand soldering flux, solder wire, alcohol, tissue

AB adhesive (modified polyacrylate adhesive, hello guys)

Sharp tweezers, small screwdriver, Double-sided tape, manual knife

Prepare consumables:

Type-c mother seat (sink plate, 6Pin), Taobao costs about 30 cents per seat, and shipping cost is 3 yuan

0603 SMD resistor 5.1K Ω, Pinduoduo 4 yuan, 100 packages (0603 means 0.6 inch, 0.3 inch wide, which is 1.6 mm in conversion × 0.8mm)

Fine wire

First, handle the type-c mother base, take a type-c sinking plate type 6Pin mother base, and two 0603 specification 5.1k Ω chip resistors:

Left base, right resistor

Before starting, it is necessary to clarify the definitions of the 6 Pins of the mother seat. There will be drawings describing them in the shopping interface. Here, I have created a diagram to make it easier to understand:

This type c of 6Pin has six pins, two ground electrodes (GND), two positive electrodes (VBUS), and two CCs. The metal casing is connected to the ground electrode and cannot transmit data.

The CC pin is Type-C used to distinguish the front and back sides and perform PD handshake. If the two CC pins are not grounded with a 5.1k Ω resistor (pull-down resistor), the PD charger will refuse power supply (the C to C charging line will not be used).

So in this modification, it is necessary to manually weld two patch resistors. Welding chip resistors is a delicate task that requires practice to perform well. Two hours of practice is enough. Remember to use soldering flux frequently, and lead containing solder is better for operation. The temperature of the soldering iron should be between 330 and 350 degrees Celsius.

If it is too difficult to weld these two resistors, the step of connecting the resistors can also be omitted. A regular A-to-C data cable can provide normal power supply.

Break off the two cc pins in the middle of the mother seat, and then break off the two GND pins on the side for later wiring:

Connect the two cc pins to ground through a patch resistor in sequence:

As mentioned in the definition of pins above, the metal casing is connected to the GND pole, so simply connect the CC pin to the metal casing with a resistor to complete the pull-down grounding.

Connect the c to c data cable of the PD charger and use a multimeter to test the voltage between the positive electrode and the ground electrode:

The voltage is normal 5V, indicating that CC pull-down resistance welding is perfect

Then handle the charging compartment. The charging compartment is fixed with a buckle, so you can use a small knife to pry it open and expose the circuit board. It is best to take a photo of the circuit board to avoid forgetting the wiring in the end:

It is best to disconnect the battery in a timely manner for valuable equipment before proceeding with subsequent operations to avoid accidental short circuit damage to the circuit.

I did not disconnect the battery here because I am proficient in the operation and can ensure that there is no short circuit. (Things are cheap, I'm too lazy to bother disconnecting and then connecting the battery)

To replace the charging port mother base, it is natural to remove the old mother base. The best tool is the "air gun". However, due to the large size of the air gun and the limited use of it, it takes up space in the box. I am too lazy to buy it, so I use the "tin stacking method", which is to pile a large lump of solder on the old base, use the melted solder to transfer heat from the soldering iron to the entire mother base, and remove the mother base.

Replace the electric soldering iron with a K head, fix the earphone box shell on the desktop with Double-sided tape (it can be operated stably without a bench vice), apply flux to the old mother base, stack tin, and remove the micro usb mother base:

K blade tin stacking micro USB base

Clean excess tin with a solder wire:

The mother base of the soldering micro USB has five pins, with the rightmost and leftmost contacts being GND and VBus, namely negative and positive, respectively. Upon closer observation, the GND contacts are connected to the "copper clad layer" on the circuit board, and they are also connected to the solder joints of the fixed base metal shell. By using the path detection of a multimeter, it is easy to determine the positive and negative contacts.

Connect flying wires (thin wires) to the ground wire and positive pole:

Afterwards, we need to fix the type-c motherboard to the original position of the micro USB motherboard. Due to the metal shell of the mother base, an insulation layer needs to be placed between the mother base and the pins below to avoid short circuits at the pins below. First, use alcohol and a tissue to clean the residual soldering flux, then apply a layer of AB adhesive to the pins, wait for five minutes to complete the curing, and then complete the insulation treatment (using alcohol to clean the soldering flux is to fix it more firmly after applying AB adhesive):

Next, apply a thick layer of AB adhesive to the insulation layer, fix the base (cure for five minutes), cut the flying wire short, and peel off the copper wire at the end:

Fix the mother seat, adjust the flying wire to connect the positive flying wire to the positive pin, and the negative flying wire can be directly connected to the mother seat shell. After welding, insert the PD data wire and test for power on:

After connecting the wires and testing, the shell needs to be installed, but the type-c motherboard is slightly larger than the micro USB motherboard, so it is necessary to polish the charging port of the shell:

I didn't control my hand properly, it's embarrassing

Finally, reinstall and test:

Test successful!

summary

For simple micro USB power supply devices, this method can be changed to type-c power supply, which will not have a significant impact on the appearance. If there is a need for power supply to the C to C line, it is necessary to weld a 5.1k Ω resistor to ground the two CC pins. This practice also explains why some devices cannot be charged with PD chargers, which is actually because the manufacturer forgot to design a pull-down resistor circuit when drawing the circuit.

In this modification, I used AB adhesive "Hello Brother", which is an excellent insulation layer on the one hand and can firmly fix the mother base on the circuit board like welding on the other hand. I am not worried about its strength at all because it is too sturdy and has a slow aging rate, which is enough to reach the end of the lifespan of this electronic product.

Special note: Do not use Hot-melt adhesive or 502 to fix this long-term plug and unplug interface!

This modification method can provide a maximum charging power of 5V 2A, and higher power fast charging needs the support of data functions. The drawback of this modification is that it cannot transmit data.

In fact, there is a Type-C motherboard on Taobao that can transmit data. It looks like this:

Type-C motherboard with data transmission function

As you can see, this motherboard comes with a small circuit board at the back, with four contacts "GND, Data+, Data -, VBus" at the back, and a CC pull-down resistor pad at the back. But this motherboard is too large, and if you want to change the charging port of an old Android phone, this motherboard obviously cannot be plugged in.

If you insist on replacing your old Android phone with a type-c motherboard, there is also a way. You can refer to these two tutorials, and the author has drawn an ultra small PCB adapter board for converting the type-c motherboard to a micro USB pin:

Embrace type-c - Micro/Mini USB is almost perfect for changing type-c

Embrace type-c, OPPO R9s change type-c

At this point, with such a modification plan, I basically don't have to worry about its old charging port when buying electronic devices in the future.

During the process of recording this modification, another deep feeling was that there was a huge difference between artificial light and natural light. In this record, I have used a desk lamp with high Color index when photographing the circuit board indoors, but the difference in color and detail between indoor and outdoor shooting is really large, which is far beyond color matching.

Source: Minority