Violent Dismantler Part I: Looking for the soul of the lamp - MI Xiaomi Mi LED intelligent desk lamp

Since most spare time is in the evening, my demand for the lamp is very large. Even though it has entered a new era of LED lighting, the design of many desk lamps is still the old idea of ​​the tungsten lamp era. However, I was unacceptable for a LED lamp that was optimized for LED sales. The LED itself is very cheap, and the driver is also very cheap. Why should I increase the number of poles by a factor of 100?

However, it is impossible to reconcile the three aspects of appearance, price, and durability. In layman's terms, there are no cheap and good things. The dismantling millet lamp in my opinion is a product of balance in all aspects, there is no high-to-take-off price, no super ugly appearance, of course, is not too cheap.

For the appearance, I think everyone will have their own opinions. However, I do not understand why the red line is a special slot.

For the price, it is more expensive than the $69 price of Midea's MTD 4.5, and there is an advantage in terms of price compared with the same Philips Philips Zhili Desk Lamp 2.

Based on the above reasons, I started my 3rd LED lamp design desk lamp: Mi Jia LED smart desk lamp. It is also the 14th lamp I purchased. Other desk lamp dismantling involves renovation and will be re-edited and released later.

Mi's smart LED desk lamp is officially priced at 169 yuan. This pricing is relatively modest, there is a certain profit, but it is not the ordinary people can not accept the high price, does not need to bite the teeth to buy a big deal next to eat the Northwest wind.

The official website is generally priced at 169 yuan, encounters festivals such as rice flour festivals, as long as it is not out of stock will have a certain degree of discount. In the past on October 18th, I didn’t know what festival was on special price to 149 yuan. This price is relatively suitable to start.

Jingdong has its own sales, and it is recommended to purchase it at Jingdong. After superimposing the entire product ticket , you can get a small discount. With Jingdong after-sales service, it is still relatively safe. The key point is that in the 211 area, Jingdong delivery is much faster than buying on the official website .

Functionality and usage aspects are worth covering. I can only write again and repeat the time. Want to look out of the box and use related can be moved:

Well, the following is the main content of this article.

Two of the three major elements of the product have already been said, so the remaining one is durable.

There are always two ways to test the durability of a product. One is to make time for the test, the other is to disassemble the analysis .

This red line can be said to be a little bit of Tucao. Only, I think it will not look better if it is replaced by yellow, green, blue, and purple. However, in order to meet the needs of the general public, some limited editions such as silver, gold, and braided lines can be introduced to meet different needs and can be sold more expensively.  

For users who have already purchased, it's good to buy a paint pen, and what colors you want to paint.

Due to the use of DC power supply, the circuit located on the base can be made very simple and light. Also, with 12V safe voltage input, you don't have to worry about the leakage of electricity to cause the shaft to become live.

Remove the bottom 3 screws and open the bottom cover. Disassembly starts from the bottom

The internal circuit is divided into two parts. The weight stable base is used around the circuit.

There is a power input and reset button on the accessory board. Personally, it feels a bit redundant in the design. These functions can be integrated on the motherboard and can also reduce the cost.

The wiring between the boards is soldered.

Welding the red, blue, and black tricolor lines to disassemble the lamp post. Because the internal line is too short, it cannot be pulled out without first disconnecting the line lamp.

There is a hexagon socket screw on each pole.

Unscrew the screws and remove the base first

Then pull out the LED light bar. The cable has an interface near the pole, but it is a pity that it cannot be reused.

There is a black snap in the shaft base for the wires of the card main body to be prevented from being pulled out or retracted.

Remove the two screws on the shaft base and pull out the shaft base. These two screws are not only used to fix the shaft base, but also to fix the internal parts of the LED lamp.

After removing the shaft holder, the wick can be pulled back.

On the back of the wick, you can see a larger area of ​​the aluminum alloy heat sink

There are clips at the entrance to prevent the wires from being pulled out. Here the clip echoes the line card in that section of the lamp post and the two work together to prevent the cable from retracting into the lamp post or being pulled out.

The LED circuit is fully adhered to the aluminum alloy support, and the entire support acts as a heat sink, which in turn is in contact with the lamp housing to extract heat. There is nothing to be picky about thermal design.

The LEDs are arranged in white light, warm light, white light, warm light, white light... Machine patches are arranged neatly.

The LED chip is relatively mini and the size can be compared with the orange 5050 patch behind it.

Three wires on the LED circuit are fully soldered and there is no soldering. Flux is ugly.

On the diffuser board, each LED chip has a concentric design auxiliary light guide at the corresponding position, making the light more uniform as possible.

As one of the focal points of the promotion, it is only a pin + pad control tolerance, and the base is a plastic one. Although it looks relatively simple, there are indeed no slots in the structure, and it is also more durable. It is not as tall as it is advertised.

The layout of the base is neat and the distance between the plates is appropriate.

There is no data transmission between the main board and the sub board. All components on the two boards are on the front, the back is clear and cool, and the circuit is relatively simple. Looking at the average life of each component, this station lamp can last a long time. The only one that hangs up will probably be the transformer (although anyway 12V is also good to find).

The motherboard uses a white PCB + red text color, I gradually prefer the color to black. The division on the main board is relatively clear, and the dimming circuit, Wifi control module, and power supply are clearly defined.

The WIFI control module is still soldered on the motherboard like a plug-in. However, unlike the chip used by other demolition millet smart products, Mijia Smart LED desk lamp uses an ESP8266EX chip as a Wifi and circuit control module with 25Q16CSIG. Flash storage firmware.

The motherboard integrates 2 sets of 3YG265 dimming driver chips, which are used to control the brightness of the yellow LED and the white LED. The color temperature is adjusted by adjusting the brightness of the two LED groups.

There are many similar interface pads on the motherboard. I guess the original design was to use the interface + cable to connect the circuit board and LED. I do not know what the reason was, but later I changed the line to direct welding. However, the pad still stays on the original circuit.

Air04 feels that the use of the interface facilitates installation and maintenance, and that the use of direct soldering in the line is more stable, does not easily fall off, and saves costs. I personally prefer to solder directly.

There is also an interesting empty pad on the secondary board. Measure the positive and negative poles on the interface. Is there a built-in battery setting on the initial design? Just like the meter home appliance fans can continue to work because of the power failure? It may be possible to remove weights, replace the polymer battery and protect the circuit to retrofit to continue this function.

Finally, all the parts are put back in place, and the LED wires are soldered back to the motherboard to restore the original status. The dismantling can be done without damage, and during the dismantling, no obstacles such as waterproof stickers and fragile labels were encountered.

The dismantling can be seen that the Mijia LED smart desk lamp has a simple structure, so long as it is not a problem, the probability of failure in subsequent use is not large. Some simple minor problems can also be repaired on their own. There is still a certain amount of DIY space on the circuit board. If the brain cavity is big enough, try its own design scheme DIY.

Slightly different from the advertisement is the physical knob switch and dimming, and the Promise Dimming in the official propaganda is only achieved on the APP side. The physical rotary switch has a "level", not the kind of damping knob on the lens focusing ring, but the aperture ring as a 嘎 嘎 up to a stall. Of course, this setting has two sides, the advantage is that does not need to rotate a long distance like the electrodeless knob can be adjusted to the desired brightness (color temperature).

advantage:

1, LED arrangement is appropriate, thermal design in place, increased LED life.

2. The detail design of the lamp body ensures the service life.

3, the diffusion plate is excellent workmanship, providing a soft light.

4, the shaft design is simple and efficient, it looks more durable.

5. The internal circuit of the base is simple in design, reasonable in arrangement, and has certain DIY space.

insufficient:

Fluxes want a better point.

I'm Air04 , thank you for watching.