This 2-6S 45W charger/discharger is based on the IP2369 power management chip and surfaces in various slightly different versions with labels like “Nuoying” or “DYKB”:
This board is a highly integrated powerbank-solution: add it to any lithium 2-6S battery pack to get a high-performance USB PD powerbank, including charging and discharging with USB PD support.
| Item | Remark |
|---|---|
| Supported batteries | LiIon, LiPo, LiFePo4 |
| Supported strings | 2-6S |
| Built-in battery protections | yes |
| Built-in output protections | yes |
| Maximum output current | 3A |
| Maximum output power | 45W (6S battery) - 18W (2S battery) |
| Output voltages | USB PD: 5/9/12/15/20V and PPS |
| DC-Converter | Buck-Boost |
The board can be configured conveniently via solder bridges (i.e. setting the battery chemistry and number of strings). No complex soldering required.
Overview
This board is a flexible powerbank solution and can be connected to almost any lithium-based battery pack (including LiFePo4). You must configure the board properly though via solder bridges before connecting any battery.
All board features are implemented by the IP2369 power management chip, so it is strongly recommended that you read the IP2369 overview before reading this article.
Highlights
There are many different power management boards on the market, but this one stands out for a number of reasons:
- LiFePo4-Support:
Most boards work with LiIon and LiPo batteries only. This board can also be configured to work with LiFePo4 batteries. - Universal Charger:
This board is a charger and discharger, so it can act as a universal charger for any 2-6S battery pack of any lithium chemistry. That’s why you can use this board as a charger only:- LiFePo4 Charger:
Small chargers for LiFePo4 - especially with more than one string - are hard to find and expensive. With this board, you can easily charge typical 12V LiFePo4 batteries. Just configure it for LiFePo4 and 4S. - Tool Batteries - Makita & Co:
Chargers for tool batteries (like Makita, Parkside, DeWalt, Bosch, Milwauki, you-name-it) are either hard to get, expensive, or low quality. With this board, you can easily charge typical 18-20V tool batteries from any USB power supply. Just configure it for LiIon and 5S. As a bonus, you also get a 45W USB PD output and can power your laptop from a tool battery.
This board is not suited for charging small batteries with low capacity: since this board charges with up to 45W, depending on the number of strings your battery uses, the charging current can reach up to 7-8A. It is also not suited for charging single cells since its minimum configuration is 2S (two cells in series).
Note also that your battery pack should have its own BMS that takes care of balancing the individual cells. With tool batteries and LiFePo4 batteries, this is the case. With your own DIY battery packs, it’s your responsibility to add a BMS.
- LiFePo4 Charger:
-
Wide Input Voltage:
IP2369 accepts any input voltage in the range of 4.5-25V, so you can - but you are not limited to - use a USB power supply to charge your batteries. You could as well use a classic voltage supply or re-purpose an old “power brick” you have lingering around. -
Full USB PD Output (including 20V and PPS):
The board outputs full USB PD and includes a highly efficient buck-boost converter. From any of the supported battery string configurations (2-6S), you get all USB PD 3 output voltages up to 20V.Via PPS, you can even request arbitrary output voltages in 100mV increments.
There are really not too many affordable and small boards that provide 20V/1.5A/30W output at just 6V input (when using a 2S battery pack). Even at this wide boost voltage gap, the board operates at 92% conversion efficiency and works reliably at comparably low heat.
-
Affordability:
All this may cost you as little as €3.50 (that was my price ordering 10 pieces, a regular order and no “welcome” offer).The normal price range for single units is 3-6€, so even if you order without much comparing and not in bulk, this board is still highly affordable.
Limitations
This board has a few limitations, too:
| Feature | Remark |
|---|---|
| Light Loads | IP2369 cannot detect loads <70mA and cuts power (≈350 mW at 5 V) |
| Charging and Output Power | While IP2369 supports limiting the power (both for charging and discharging) from 45W down to 20W, this board does not expose the required RPSET resistor |
So if you plan to use this board to power i.e. a microcontroller that may enter deep sleep, it is not the best choice:
- this board targets very high USB loads and would be an overkill for small loads.
- as most powerbank boards do, it cuts power output once the load drops below 70mA, so it would cut power once your microcontroller enters deep sleep.
Light Loads and Workarounds
Most power management chips cannot “see” light loads. For IP2369, the blind spot starts at power consumption less than 350mW (70mA at 5V).
In the datasheet, it reads: “the board automatically turns off the power output if a “light load” is detected.”
The truth though is that IP2369 cannot “detect” a light load, rather it fails to detect small currents. So when the load drops below 70mA, it becomes undetectable. At this point, the chip cannot differentiate anymore whether a load is running or not.
To somewhat heal this situation, most power management chips do not shut down the output immediately when no load can be detected anymore. Instead, they start a grace timer.
With IP2369, the grace period depends on how the load was supplied with power:
- Normal (Non-USB PD) Load:
If the load uses 5V and has not negotiated any other voltage or current using USB PD, the grace period is 32 seconds. - PD Protocol:
If the load is using USB PD, the grace period is 16 minutes.
Keeping Output open
If you need to run a load below the chips’ detection range, i.e. a microcontroller in deep sleep, here are the options:
- Brute Force:
Add additional loads, i.e. LEDs, that raise the power consumption over 70mA so that the chip can “see” the load. - Reset Grace Period:
Wake up the microcontroller in regular intervals to temporarily increase the current above the detection threshold. This resets the grace timer and keeps the output open. - Change IP2369 Behavior:
Use a microcontroller and I2C to change the IP2369 settings: simply disable the “automatic output shutdown” altogether. This keeps the output open at all times, regardless of load type.
Note: Public I2C register maps for IP2369 are scarce; plan for experimentation or vendor documentation if implementing firmware control.
Adjusting Maximum Power
IP2369 supports limiting the power (both for charging and discharging) from 45W down to 20W. This can make sense if you design a powerbank with a smaller battery that cannot handle 45W charging and/or discharging.
Setting the power limit is configured via an RPSET resistor, however the board does not clearly expose this resistor. There is just one resistor on the PCB that is specifically marked (R10), however the purpose of this resistor is undocumented.
If you need to limit the power, you would have to identify where the board has located the RPSET resistor. Next, you’d have to replace the existing (tiny) SMB resistor with the resistor value for the output power you want to use.
A much more convenient approach is to use I2C to change the maximum power digitally. This requires an external microcontroller, though.
Practical note: 45 W is the SoC’s envelope and is achieved only when the negotiated voltage/current and internal 3 A input limit allow it (e.g., 20 V ≈ 2.25 A PD profile). At lower negotiated voltages, the effective ceiling is lower.
Caveats
When using this board in your own projects, here are a few considerations to avoid issues.
This board is a high-performance buck-boost converter that can output considerable power at a much higher voltage than your battery pack. This can induce high currents at your battery pack level.
For example, in a 2S battery configuration, the board can output up to 20V and 1.5A (30W). At the 6V battery, more than 5A are drawn.
Quick check: input current ≈ P_out / (V_in · η). Example: 30 W at 6.0 V with η ≈ 0.92 → ≈ 30 / (6.0 · 0.92) ≈ 5.4 A.
- Battery pack:
Sufficient battery capacity (i.e. >6000 mAh at 2S configuration) ensures that the battery can safely provide the high currents required. Most lithium batteries safely charge and discharge at 1C. -
Wiring:
Wires must be short and thick to avoid voltage drops and heating up:- Fire Hazard:
If your wires are way too thin (i.e. AWG 24 and higher), they will heat up so much that they can melt and cause a fire. -
Malfunctioning Charger:
If your wires are only slightly too thin (i.e. AWG 20-AWG 22), they cause a significant voltage drop at the high currents involved.To the charger, the battery voltage now always seems lower than it really is (true battery voltage less the voltage drop). That’s why the charger might overcharge the battery, and over-discharge protection may kick in long before the battery is truly empty.
- Fire Hazard:
Thermal tip: sustained 2S→20 V at 1.5 A will warm the inductor and backside copper; provide airflow or mount to a small aluminum baseplate if enclosure temps rise.
In a nutshell:
- use AWG 18 or AWG 16 wires.
- use battery packs with a capacity of at least 6.000mAh, especially in 2-4S configurations.
- make sure your battery pack has a BMS that takes care of balancing the battery cells.
Board Versions
This board is available from different vendors and can be labeled Nouying or DYKB.
While the board design is identical, there are significant differences. Since there is no documentation, the following information is strictly empirical from the boards I received from different vendors:
| Item | Nuoying | DYKB |
|---|---|---|
| PCB quality | good | good |
| PCB Labels | good | poor |
| TVS Diode | mostly present | always missing |
| Inductor | 6.8µH | 4.7µH |
Application tip: prefer 6.8 µH when targeting heavier 2S→20 V laptop loads or EMI-sensitive builds; prefer 4.7 µH when peak efficiency is prioritized and ripple/EMI can be tolerated.
What makes matters worse, even the same board type (like Nouying) can be configured differently, based on batch. While most Nuoying boards came with a TVS diode in place, some boards were lacking it:
DYKB boards were more consistent in the sense that they always lacked the TVS diode.
In a nutshell, all board variants work well. While a TVS diode adds additional protection, it certainly isn’t crucial for designs where the battery is soldered directly to the board. So whatever board version you get, most likely you will be happy with it.
If you are interested in the subtle differences, read the details below.
Differences: Nouying vs. DYKB
Label Quality
The Nouying board is clearly labeled, and you can easily identify the solder bridges for the different battery string configurations:
On the DYKB board, labels are hardly recognizable and become visible only in large magnification:
Both boards are preconfigured for 4S LiIon/LiPo batteries.
Heat Sink
On the back side, the Nouying board (left) uses a slightly more efficient heat sink than the DYKB version with its simple rectangular shape (right):
TVS Protection
The Nouying board typically (but not always) uses a TVS diode close to the B+ connector (the black item labeld CK in the background of the picture).
The DYKB board leaves the diode unpopulated:
The TVS diode protects against voltage spikes that can originate from varoious situations:
- Hot-Pluggable Battery:
If the battery pack is not soldered directly to the board, battery plug-in/out can create fast overshoot ringing; a TVS damps/clamps it, omission means the spike propagates into the buck-boost/input caps and IC pins. - ESD:
Charged cables or user ESD can inject kV pulses; the TVS provides a low-impedance path and lowers clamping voltage seen by silicon. Without it, protection relies only on internal diodes and layout.
Parts may not fail immediately but suffer reduced lifetime or intermittent faults after repeated stress events.
Even though the added safety from this TVS diode can be argued for the typical “powerbank” use-case where a battery is permanently attached, the Nouying comes with this protection, and the DYKB has saved a few cents by leaving the TVS diode unpopulated.
Inductor
Nuoying uses a 6.8µH inductor whereas DKYB uses a 4.7µH inductor. 4.7µH is the inductor value of the reference schematics in the IP2369 datasheet.
In reality, both inductor values presumably work equally well, however there may be subtle differences:
| Item | 4.7µH (DYKB) | 6.8µH (Nuoying) |
|---|---|---|
| Ripple | higher | lower |
| Efficiency | better | worse |
| Light Loads | worse | better |
| EMI | worse | better |
Rule of thumb based on the different inductor value:
| Board | Use Cases |
|---|---|
| Nouying | targeting 2S→20 V laptop loadsheavier sustained loadsEMI‑sensitive buildsminimizing ripple/peaksmore thermal headroom |
| DYKB | follows IP2369 reference inductance (4.7 µH)slightly higher peak efficiency possible at some loads (lower DCR)okay when thermal/EMI margin is available |
SMB Resistors
Both boards seem to use different SMB resistors at some places on first look. However, this is not the case:
- Different Labeling Systems:
01Cis equivalent to103, and both are 10 kΩ values. - Variantions within allowable range:
For example, Nouying uses01C(10 kΩ) for the 4S setting whereas DYKB uses912(9.1 kΩ). - Solder Bridge:
The DYKB board uses a000resistor for the default solder bridge (0 Ω jumper). Nouying uses a015(0.15 Ω), presumably because of a lack of000.
The different SMB resistor labels rather seem to indicate that this board is produced by various manufacturers.
Nouying Configuration
DYKB Configuration
Exploring the board
Front View
On the front side, the board features:
- Push Button:
Manually enable (single click) or disable (two single clicks) the power output. - USB-C Connector:
In-/Output. Can be used to charge the battery, and provides USB PD output when running from the battery. - Four LEDs:
Indicate battery state-of-charge, and charging progress when connecting to a USB power supply. -
MOSFET:
AGM405AP or similar N-channel power MOSFET, most likely used as an “ideal diode”: when the board sources power (discharge mode) it doesn’t leak back into an attached charger, and when sinking (charging) it blocks system voltage from returning to the port if disabled
LED Indicator
The board implements a 4-LED indicator located next to the USB-C connector.
Charging:
| Battery Capacity | LED1 | LED2 | LED3 | LED4 |
|---|---|---|---|---|
| full | 💡 | 💡 | 💡 | 💡 |
| 75% | 💡 | 💡 | ⚡ (0.5Hz) | |
| 50% | 💡 | ⚡ (0.5Hz) | ||
| 25% | ⚡ (0.5Hz) |
💡 = on, ⚡ (0.5Hz) = slow blink, empty cell = off.
Discharging:
| Battery Capacity | LED1 | LED2 | LED3 | LED4 |
|---|---|---|---|---|
| full | 💡 | 💡 | 💡 | 💡 |
| 75% | 💡 | 💡 | 💡 | |
| 50% | 💡 | 💡 | ||
| 25% | 💡 | |||
| 0% |
💡 = on, ⚡ (0.5Hz) = slow blink, empty cell = off.
When the over-discharge protection kicks in (battery empty), all four LEDs flash 4 times, then turn off.
Push Button
The board automatically enables power output when a load is plugged in, and disables it again when the load is removed.
When the load is very light, it may be undetected, and the power output needs to be manually turned on via a push button that is located next to the USB-C connector.
Any push longer than 100ms and shorter than 2s is considered a “short push”:
- 1x Short Push:
Enables the power output and turns on the LED state-of-charge display. - 2x Short Push:
Disables power output and enters low-power mode.
Side View
On the side, to the left there are the battery connectors, and next to the B+ connector, the Nouying board typically (but not always) populates the protective TVS diode (labeled CK, big black component) whereas the DYKB board leaves the diode always unpopulated (at least with the batches I received).
In the background, the large inductor is visible. The inductor is used both for buck and boost.
| Item | Nouying | DYKB |
|---|---|---|
| Inductor Value | 6R8 (6.8µH) |
4R7 (4.7µH) |
In the middle part, you see the IP2369 power management chip. On the right side, the solder bridges for the battery configuration can be seen.
Battery Pack
The battery pack is connected to B+ and B-.
- Protections/BMS:
The board comes with all necessary protections, so the battery pack does not necessarily need its own protections (although recommended). - Balancing:
Always use a separate BMS for your battery pack that supports balancing. - Wires:
IP2369 limits input currents to 3A/45W. Depending on your battery configuration, there can be much higher currents at the battery terminal. For example, in 2S configuration, the maximum battery current can reach 7.5A.
Configuring Battery Type
Both string configuration and battery chemistry can conveniently be configured using solder bridges. By default, the board is configured for 4S and LiIon/LiPo chemistry:
LiFePo4
For LiFePo4 batteries, close the solder bridge marked Li-fe.
2-6S Configuration
Bridge the appropriate solder bridge for your battery packs’ string configuration.
Always make sure that only ONE solder bridge is bridged. The solder bridges enable an internal resistor. If you accidentally bridge more than one solder bridge, the total resistor value decreases (resistor parallel connection), and the effective string configuration may be lower than required.
Tags: Nouying, DYKB, IP2369, 45W, Charger, Discharger, Li-Ion, Li-Po, LiFePo4, Powerbank, USB-C, USB PD, PD3.0, PD3.1, PPS,Boost, Buck, Buck-Boost, Light Load, I2C, Power Management, Battery Charging, Laptop Charger, Tool Batteries, Makita, Bosch, DeWalt, PPS 100 mV, ESD, TVS
Slow Website?
This website is very fast, and pages should appear instantly. If this site is slow for you, then your routing may be messed up, and this issue does not only affect done.land, but potentially a few other websites and downloads as well. Here are simple steps to speed up your Internet experience and fix issues with slow websites and downloads..
Comments
Please do leave comments below. I am using utteran.ce, an open-source and ad-free light-weight commenting system.
Here is how your comments are stored
Whenever you leave a comment, a new github issue is created on your behalf.
-
All comments become trackable issues in the Github Issues section, and I (and you) can follow up on them.
-
There is no third-party provider, no disrupting ads, and everything remains transparent inside github.
Github Users Yes, Spammers No
To keep spammers out and comments attributable, all you do is log in using your (free) github account and grant utteranc.es the permission to submit issues on your behalf.
If you don’t have a github account yet, go get yourself one - it’s free and simple.
If for any reason you do not feel comfortable with letting the commenting system submit issues for you, then visit Github Issues directly, i.e. by clicking the red button Submit Issue at the bottom of each page, and submit your issue manually. You control everything.
Discussions
For chit-chat and quick questions, feel free to visit and participate in Discussions. They work much like classic forums or bulletin boards. Just keep in mind: your valued input isn’t equally well trackable there.
(content created Aug 31, 2025 - last updated Sep 05, 2025)