Rebuild of Panasonic BQ-830 charger

Panasonic BQ-830 charger is produced by Panasonic Company is a kind of designed for Ni MH rechargeable battery a kind of high-grade charger, Small PCB Board actually has 7 IC, work more fine, the principle is to convert the external 5 V or 12 V Direct current through the internal switch power supply to output high current pulse current, for the Ni-MH battery pulse charging, with battery power detection, full of self-stop, overheating protection, in addition, each of the four batteries has a separate charging and detection circuit, which is the first choice for charging the Ni-H battery of digital cameras. However, all the internal design defects have been officially recalled, it has now moved to various second-hand markets, and now the general online price is about 20 yuan. In fact, after a simple transformation of this charger, its charging effect should be far better than many domestic chargers of-yuan commercially available.

Charger design defects mainly include, charging current is too large, the battery fever is serious; temperature protection value is too high.

Charger Transformation: (Network Method)

In order to solve the above problem, I have obtained a better transformation method through multiple tests. Although some people have transformed it online, they only paid attention to the small current and did not pay attention to the reference voltage!

Transformation: reduce the current (because the charger cannot automatically reduce the current in the future, so the overall modification can only be done ). the current cannot be reduced without limit. After my test, the minimum value is 2a (the current of the charging current source, the original value is 3.2a), which is too small to work properly (it may be a protection, after filling, it will show full ).

Method: Find the extra-large 33 m euro resistance r46 (r033). For example, if you change it to a 47 M Euro, you can find two 0.1 M Euro parallel connections. we recommend that you use a steel knife to scrape the original resistance to 47 milliliters. to scrape a few knives, You need to test the current (you can also use the large current Ohm's Law)

Rebuild 2: Modify the reference voltage. it is very easy to find a 10 k resistor and connect it to R26. The resistor is located next to the USB interface, and there is a small transistor and a tl431 on the front of the circuit board. It can be cross-connected by the two red-dot tin points shown in, you can also try the K resistance.

Other transformation methods

It is the most critical to use the method of modifying the sampling resistance. proof of practice. this is the most successful and effective method. is to find the resistance of R32. this is a sampling resistor, which is directly connected to a suitable resistor. you can adjust the charging current. it even reduces the detection sensitivity of the internal resistance of the battery, so that the garbage can be identified by the battery. at the beginning, I first connected a 700-euro adjustable potentiometer to a 100-euro resistor. to avoid short-circuit R32 caused by potentiometer rotation, the first test is the rejection problem. first adjust the potentiometer to the maximum of several rejected batteries on the hand. put it on, but there is still no response. then the resistance is gradually reduced. re-import the battery once each rotation. it was almost changed to over 400 euros. the battery can be recharged. then increase or even disconnect the resistor during the charging process. charging and Maintenance. that is to say, first reduce the sensitivity of the internal resistance detection, after charging. disconnect the circuit. you can successfully charge the rejected battery. tested. as long as the resistance is reduced by about 100 Euro. it can even charge the alkali power of South captured. hahaha, but it is best not. it's too dangerous.
During the charging process. the resistance can be adjusted at any time, and the charging current changes immediately. The larger the resistance, the larger the current. when I enter 5 V. single battery. the default current is 1A. the charging current can even be reduced to about 0.1a to 1A. it is almost a slow charge. originally, I was prepared to directly install an adjustable Potentiometer in the shell. later I thought it was unnecessary. after all, because there is no current meter to monitor the charging current in real time, and then we will consider using a 1 K and 510 euro resistance with a mobile switch. 1 K and 510 euro in parallel when the switch is switched, after detection. the overall charging current is reduced because there are too many combinations. I printed a table to overwrite and paste it to the back. the evidence is traceable.