Added a link in the OP.
Thanks for the info.
Thanks!
What chips have you identified?
Could you post pictures of the circuit board?
I don't see any 6.2M listed in the link provided.
- 10 units each of 1M, 1.5M, 2M, 2.2M, 4.7M, 10M, 1.2M, 3.3M, 5.1M, 3M
explain V-form?
It means he wired the two smaller resistors in series, then the set in parallel with the existing r5 resistor. The 3 resistors would physically form a triangle. If you stack the single larger resistor as recommended, you won’t need to bother with this.
KuoH
OH. I see. Then you could also solder 1.5M, + 4.7M,= 6.2M in series, then solder it in paralell to R5.
Is the 4.25V figure in the OP the voltage of a cell after it has been charged or is it the voltage of the charger taken while the charger is empty while plugged and measured the the + and - ends?
The measured values around 4.25V is the end voltages during charging. I have a piece of alu foil in each end of the battery and a Fluke 179 voltmeter with MINMAX function enabled connected to the foils. It stores the max voltage on the display.
May I know the voltages taken from the cell/s that was charged AFTER it was taken from the charger? (not DURING charging)
The main IC is a 14 pin unknown circuit (there are no markings on it). There is a separate 6 pin booster to make 5V marked AL579 but I have not yet found it by Googling. There are 3 MosFets marked 2300, a 3 pin Voltage reference TL431, marked 431, and a lot of other components. Interresting is that the charging current comes from an extra switcher, not directly from the 5V input.
I don't have that information, that is up to the type and age of battery, especially the inner resistance. I use different batteries, old and newer. It is not the battery, but the charger I am evaluating.
4.25V for charging is quite normal, so other than standardizing end voltage and increase battery endurance per OP wish, other members with regular charging use might not need to do this procedure.
Just my viewpoint, this mod slows down charging a bit and leave you with less charge capacity (and of course in doing so increase battery lifespan).
Right! Nice sum up.
You can also use this fix for the 4.35V position if you only have 4.30V cells. Remember that all voltages are changed by the same percentage.
It seems to be a good charger. I just miss lower charge currents. 0.5A is not really good for many batteries. I can only think of 18500, but for 14500 and smaller, I want 0,25A or lower.
New feature in OP. Set your own current.
Have you checked what those changes do to the NiMN charging behavior?
With an unmodified one, AAA NiMH cells get warm on the 0.5A setting.
I have no clue what method this charger is using charge NiMH cells though.
I think it is quite normal that AAA NiMH get warm at 0.5A.
I just made myself a mod with 50/100 mA charge current for charging some incoming 10180. I have no intention of using that unit for charging NiMH. Let's see what HKJ finds out about the NiMH charging method and we can act accordingly.