TLV431 + LM339 Battery Monitor

@markoa7

Hi, innovative solutions for complex problems just like your TLV431 + LM339 Battery Monitor project. My deep understanding of various platforms including KiCad/Eagle/Altium and my proficiency with SPICE or LTspice would be invaluable in creating the schematic you need to monitor the Li-ion battery effectively. I’ve been intrigued by your openness to suggestions for improvements, as it resonates with my working philosophy. I don't just stop at merely addressing the technical requirements; I leverage my creativity to propose meaningful upgrades whenever possible. Moreover, given that we are using flexible platforms such as esay eda pro and relatively new components like TLV431, our collaboration would breed out-of-the-box but efficient circuit designs. I am thrilled by the possibility of turning your ideas into reality through meticulous design and development. The fact that your project encompasses majority of my core competencies: PCB Design and Firmware Development is making it a perfect fit for us. Choosing me will not only give you access to a skilled professional in Marko Aleksic but also a passionate partner committed to your Project's ultimate success.

@hayat38402

Hi, how are you doing? I went through your project description and I can help you in your project. your project requirements perfectly match my expertise. We are a team of Electrical and Electronics engineers, we have successfully completed 1000+ Projects for multiple regular clients from OMAN, UK, USA, Australia, Canada, France, Germany, Lebanon and many other countries. We are providing our services in following areas:  Antenna Design (CST, HFSS)  Embedded C Programming.  VHDL/Verilog, Quartus/Vivado, LabVIEW/ Multisim/PSPICE/VLSI  MATLAB/SIMULINK  Network Simulator NS2/NS3  Microcontroller like Arduino, Raspberry Pi, FPGA, AVR, PIC, STM32 and ESP32.  IDEs like Keil MDK V5, ATmel studio and MPLab XC8.  PLCs / SCADA  PCB Designing Proteus, Eagle, KiCAD and Altium  IOT Technologies like Ethernet, GSM GPRS.  HTTP Restful APIs connection for IOT Communications. Also, we have good command over report writing, I can show you many samples of our previous reports. Kindly consider us for your project and text me so that we can further discuss specifically about your project's main goals and requirements.

@cnarvaez1957

Hello... I am very familiar with the TLV431 and the LM339 quad comparator. I understand the Li-ion cell charging process. I can simulate the circuit and also build the physical assembly. I use KiCad for schematics and Proteus for simulation, though I can also use SPICE or LTspice. Please check my profile. Best regards.

@mahmoudralizadeh

Hi, so you need a self-contained TLV431 + LM339 schematic that trips at 4.20V for single-cell Li-ion, with a small hysteresis window to avoid chatter near the threshold, plus a BOM and the calc notes showing how the divider values were chosen — all done in KiCad. That's a clean, well-defined circuit. I'd size the TLV431 divider off its 1.24V reference to hit 4.20V, then add a feedback resistor from the LM339 output back into the divider node to set the hysteresis band (a few tens of mV is usually enough to kill chatter without hurting accuracy). I'll keep the divider current low to stay under your 300µA target. I can deliver the KiCad schematic + PDF/PNG, BOM with part numbers and tolerances, and a short calc sheet. Happy to add an LTspice threshold plot if that's useful to you.

@ahmedy607

Hi, I’ve carefully read the requirements. I can design the complete TLV431 + LM339 battery monitor in EasyEDA Pro, including the 4.20 V threshold calculation, low quiescent current, BOM, calculation notes, and schematic/PDF. For the hysteresis, I would use a feedback resistor around the LM339 threshold network rather than disturbing the TLV431 reference itself. This gives controlled switching points and prevents chatter around 4.20 V while keeping the reference stable. I can also provide an LTspice simulation to verify the threshold and hysteresis if required. Best regards, Ahmed

@shivkantverma

Hi, Greetings! I am interested in working on your project. Please share the design details, specifications, and project requirements so we can discuss them further. I look forward to working with you. Thank you. Shivkant Verma

@hamzaePCB

Hello, I reviewed the TLV431 + LM339 requirement. Before fixing the resistor values, I would clarify a few points: Do you want the LED to turn ON exactly when the battery rises to 4.20 V, and at approximately what voltage should it turn OFF again? For the ≤300 µA requirement, does this limit include the LED current, or only the monitoring circuit itself? Is the LM339 output intended only for the LED, or do you also need a logic output for another circuit/MCU? Do you already have specific TLV431 and LM339 part numbers/packages selected for EasyEDA Pro, or should I select suitable available parts? I would calculate the threshold and hysteresis network from these requirements, including resistor tolerances and the LM339 open-collector pull-up, then verify the 4.20 V switching point and hysteresis by simulation before finalizing the EasyEDA Pro schematic. Deliverables can include the EasyEDA Pro source, PDF schematic, BOM, calculation notes and simulation results. I am also based in Morocco, so we can communicate in French if you prefer. Best regards, Hamza

@alabenghozzi

Hello, I read through your project details, and this is right in my wheelhouse. I have recently worked on a very similar single-cell Li-ion battery monitoring project using the TLV431 reference and an LM339 comparator, so I already have a proven, optimized circuit topology ready to go for this exact application. I will carefully calculate the resistor divider network around the TLV431 using standard precision 1% tolerance resistors to trip cleanly at 4.20 V, incorporating a well-designed positive feedback loop to introduce clean hysteresis and completely eliminate chatter at the threshold while keeping the total quiescent draw comfortably below 300 µA. You will receive full schematic source files along with high-resolution PDF and PNG exports, a concise BOM with exact part numbers, values, and tolerances, calculation and design notes explaining the threshold and hysteresis math, and a ready-to-run LTspice simulation confirming the transient trip point and hysteresis window. Since I already have the core simulation and schematic architecture proven, I can deliver this quickly, and if you decide to proceed with the PCB layout afterwards, I would be more than happy to seamlessly transition the schematic into a compact, professional board layout. Let’s chat to get started, I can share snippets or discuss my previous design right away!

@JagdishCK

Hello, I shall provide schematic, BOM, calculations & even simulation in LTspice. This is simple requirement and could be handled well ensuring low power consumptions. Having 20+ years of experience, I specialize in analog electronics, low power, EMI-EMC design. Please see my profile below, https://www.freelancer.com/u/JagdishCK Please message me for any clarifications. Regards, Jagdish Karamchandani

@mandalsurajkumar

Hii there, It's my pleasure to write to you that I can help you in completing this task in TLV431+LM339 power monitor module. I am an electrical engineer having 5+years of experinece in power electronics hardware design. I have directly used these module for my project. I will provide you clear, self-contained schematic that uses a TLV431 shunt reference and an LM339 comparator to monitor a single-cell Li-ion battery and flag the full-charge point around 4.20 V. The deliverables for this as per your requirement will include: Create the diagram from scratch (PDF, PNG, or a file from KiCad/Eagle/Altium—whatever you prefer). • Choose and calculate all resistor values so the reference network trips at 4.20 V with a small amount of hysteresis to prevent chatter. • Keep quiescent draw low (≤ 300 µA preferred). • Include a concise BOM and short calculation notes showing how you arrived at the divider and feedback values. • Optional but appreciated: SPICE or LTspice plot confirming the threshold. Kindly connect and let's discuss details of the project. Regards,

@Abdurhaman

​I can design this Li-ion battery monitor circuit for you in EasyEDA Pro. I have solid experience with analog circuit design, power management, and comparator hysteresis networks. ​Technical Thoughts on Hysteresis: ​Hysteresis on LM339, Not TLV431: The TLV431 needs \ge 80\ \mu\text{A} cathode current to hold its 1.24\text{ V} reference. Adding feedback across it destabilizes regulation. Hysteresis should be applied across the LM339 using a high-value feedback resistor (1.5\text{ M}\Omega\text{--}2.2\text{ M}\Omega) to the non-inverting input. ​No Chatter: This gives a sharp 30\text{--}50\text{ mV} hysteresis window at 4.20\text{ V}, preventing chatter as the battery tops off. ​<300\ \mu\text{A} Quiescent Draw: Biasing the TLV431 at \sim 100\ \mu\text{A} with 1\% high-impedance divider resistors keeps overall idle current around 200\text{--}250\ \mu\text{A}. ​Deliverables: ​EasyEDA Pro native project, schematic files, and high-res PDF/PNG. ​Complete BOM (1\% resistor tolerances, active LCSC/Mouser part numbers). ​Concise calculation write-up (divider math, hysteresis window, power budget). ​LTspice simulation .asc file and waveform plots proving the 4.20\text{ V} trip point. ​Price & Timeline: ​Timeline: 2 Days to first complete draft. ​Ready to start in EasyEDA Pro immediately. Let me know if you'd like to move forward!

@jvank2

This is an easy task for me and I can do it for you. If you are interested, then write me! Very important for me, that you are available to see my messages. Thank you, from Austria to Morocco! :)

@udbheda

Hi there, I am an electronics hardware engineer with strong expertise in analog circuit design and low-power systems. I can design this 4.20V Li-ion battery monitoring circuit for you quickly and accurately using EasyEDA Pro. My Approach & Quick Thoughts: Tool: I will design the schematic entirely in EasyEDA Pro, ensuring it is clean, well-labeled, and easy to read. Circuit Logic: I will use the TLV431 to generate a stable precision reference voltage (1.24V). A high-impedance resistor divider will scale the battery voltage down to compare against this reference at the LM339. Hysteresis Strategy: To prevent output chatter around the 4.20V threshold, I will add a high-value feedback resistor (positive feedback) from the LM339's open-collector output to its non-inverting input. This will create a clean, crisp switching action. Low Quiescent Current: By carefully selecting high-value resistors (in the 100kΩ - 1MΩ range) for the divider and utilizing the low-power characteristics of the TLV431 and LM339, I will easily keep the total current draw well below your 300 µA limit. Deliverables: EasyEDA Pro source files + High-res PDF schematic. Complete BOM with exact part numbers and tolerances (1% resistors). A short PDF note detailing the exact math for the voltage divider and hysteresis feedback network. I can complete this within 24 hours. Let's chat to get started! Best regards, Uday Bheda