Power management

test posting without tags

Hi, I am designing a 25W power supply for the raspberry pi 5 for my battery powered project. The buck regulator I am using has a fixed 5V output and I want to use the STUSB4710 to offer 5V 5A to the Pi. How can I program the registers to do so via I2C? I have checked the datasheets as well as the STUSB47XX register maps but both are still quite vague on how to program.

Hi,I am presently planning to use Viper265K part for High Voltage Buck converter design with below requirements: MinMax  Vin200900V Vout4.5 V+/-5%Iout0.44 A Pout2 W  With above requirements the duty cycle for the device is observed to be 0.5%. Please can you help me to know if the device can be used for such low duty cycle and what would be recommendation from your side for achieving above design requirement.

Are there any more resources to understand how to use STEVAL-HARVEST1, how does the energy flow from super capacitors to the MCU and also the back up capacitors. I feel few things are missing the schematic and the user guide. I want to first implement a small UART program with energy harvesting. Can anyone guide through steps in achieving it. How to connect this to board, does it mean I need to add any external wire from harvester solar panel and short it here?I have read https://www.st.com/resource/en/user_manual/um3539-getting-started-with-stevalharvest1-energy-harvesting-board-for-nucleowl55-stmicroelectronics.pdfhttps://www.st.com/resource/en/schematic_pack/steval-harvest1-schematic.pdfhttps://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=11369460Thanks in advance.

I have some questions regarding the L78M05AB regulator IC.1. Could you please investigate the temperature at which this IC's the thermal protection actually activates?2. I have been informed that the thermal protection mechanism shuts down the output voltage.    However, when we applied heat, we observed behavior suggesting that the output appears to remain at a constant level.    If the temperature is kept at a specific value, will the output remain constant (for example, 3V)?"3. Could you please clarify the behavior when SOA protection is triggered?    Does the circuit limit the output, or does it enter a shutdown state?4. Related to SOA protection, is there any case where the voltage is reduced and latched at a certain level?5. Are there any restrictions or specifications regarding harmonics or noise on the input voltage of the regulator IC?  

Hi, The L9945 driver used in our proprietary automobile controller unit responsible for controlling actuators and pumps in exhaust system regulating harmful exhaust gases adhering to emission control policy. Case1: OUT 2 channel: Nominal frequency = 800 Hz, Max = 1000Hz Short to Battery (STB) •        Function is consistent till 99.99% and no failure detected till the range. •        However, setting the frequency to maximum requirement 1000Hz caused failure even at 80% TON itself. Short to Ground (STG) •        Failing after 98% with nominal frequency – no STG detection, detecting as open load Open Load (OL) •        Failing after 98% with nominal frequency – no OL detection. SPI command for channel 2: 0x26000082 Case 2: OUT 3 & OUT 7 channels: Both channels are configured as individual low side with same parameters Nominal frequency = 10 Hz S

 Hello,I'm migrating STSW-STPM004 firmware from IAR to STM32CubeIDE (GCC).The metrology_STPMS2.a library was compiled with IAR and causes UsageFault(CFSR=0x00008200, INVSTATE bit set - ARM/Thumb interworking issue)when linked and run with GCC.Is there a GCC-compatible version of metrology_STPMS2.a available?Or is the source code available for recompilation with GCC?Environment:- Board: EVALSTPM-3PHISO Ver 1.1- Firmware: STSW-STPM004- IDE: STM32CubeIDE 2.1.1 (GCC 14.3, arm-none-eabi)Thank you   

Hi, Im using the L9963E for a Battery Management System. I noticed that the device has a register called "FSMstatus". I don't understand if reports the current status or the previous status. For example, if the device is in SLEEP, in order to read the FSMstatus register, I have to wake it up, and the device goes to the NORMAL state. Now the FSMstatus reports the SLEEP or NORMAL state? Unfortunately I cannot try the code.  

Can you help me to finde the Part number in the foto BEV GP 344.

Dear ST community, I'm reviewing the Vac sense circuit of STEVAL-7BIDIRCB, where the circuit uses a resistor divider to generate a low voltage of VACN and VACL for MCU. I simulated this section of circuit in LTspice, and here is my result : My Vac input is +/-256V sine waveform and VACL that I'm measuring is +/-900mV sine waveform. Based on my calculation this is a simple voltage divider and I should see +/-1.8V sine waveform. Why am I seeing 1.8V/2 = 900mV ?   I did some research and my understating is that when there is an equal resistor network each side of AC source ( N and L), Vac IN  becomes half ( 256V -> 128), but I don't understand how it is possible when my Vac input is 256V ?   

Hi everyone,I am designing a custom Power Distribution Board (PDB) handling up to 200A at 24V. This PDB will eventually interface with an STM32 and a Jetson Orin Nano for telemetry and control, but my current focus is solely on verifying the robustness of the analog/power switching layer.I would love to get your thoughts on the pre-charge (soft-start) and emergency shutdown logic I’ve implemented, as well as the layout approach. Here is the operational breakdown of the circuit:Turn-On & Soft-Start Sequence: When the main switch is closed, Q1 directly pulls K1's coil to GND, turning it on. The pre-charge resistor (R3) starts charging the bulk capacitors (C1, C2). Simultaneously, the RC timer network (C3 + R5 / 220k) starts charging. After about 1-2 seconds, it triggers Q2, which then pulls the main contactor K2's coil to GND. K2 closes, taking over the 200A main load and dropping the current through the R3 pre-charge resistor to near zero. Note: I can always swap R5 to 330k or 470k

  I am testing the board with a 14s Li-ion battery, but I am unable to read the cell voltages or configure any register through the GUI. I shorted the X1 and P2 power supply inputs and supplied 12 V to both. This was the only setup in which I could get a green ACK indicator. The results were: Only cell 1 showed a voltage, but it was incorrect (5.8 V). When I try to write or read any register, I receive an ACK, but the register value does not remain as written. I also tried to connect VBAT (P2-15) to C14 (by soldering R22) and GND (P2-9 or 23) to C0, but in this configuration the device does not start and the D13 LED does not blink. I tried several times, resetting all the power supplies in different sequences, but I still could not communicate with the device. After returning to the initial setup, powering the L9963 with 12 V, I was again unable to configure the ID or take any measurements.    

can someone help me with communication of l9961 chip to get voltages of 4s cells n current n charge accumulated by using esp32 or aurdino i dont have this chip n i am not a coder i tried my best but can get any data from the chip just i2c add 0x49 n this register 0x00 gives  0x41 n nothing please hep

Hello, we are in the process of developing a BMS using an STM32 and L9961. We were wondering if there was any source or example code of a full BMS we could have access to in order to speed up our development. I am aware of the example code on the product page but was hoping there would be something more fleshed out. In addition, I wanted to know if ST has a vault of cell models that we can use with the BMS for fuel gauging? We use Molicel P50B cells and plan to use Molicel P60B cells in the future. Thanks,Jon

Dear ST Technical Support Team,I am currently using the ST1S10PHR buck converter in my custom PCB design to convert 12V input to 5V output.However, the regulator is not switching to the expected 5V output. The measured output voltage remains around 0.79V.Below are the measured and design details:Input Voltage: 12VVIN_SW and VIN_A pins: Confirmed 12V presentEN (INH) pin: 12V present (device enabled)Expected Output Voltage: 5VMeasured Output Voltage: ~0.79VFeedback Resistors: R1 = 11kΩ, R2 = 2kΩInductor: 3.3µHSwitching frequency: Internal 900kHz (SYNC connected directly to GND with short trace)GND and EPAD connected to ground planeOne concern in my PCB layout is that the SW pin to inductor trace length is approximately 47mm. Although the inductor is placed near the IC, the copper routing from SW to the inductor became long due to layout constraints.The board powers up correctly, and all input pins measure properly, but the output remains close to the feedback reference voltage (~0.8V) an

Hi all,I connected my SPV1050 chip as you can see in the picture and started to measure my circuit. It looks pretty good. I powered it up with 3.3V at IN_LV. And I can measure a voltage of about 2.416V at the STORE pin. And even the LDO2_EN pin got a 2.412V, but at the LDO2 pin there is nothing. Does anyone have any idea why this might be the case? Even when I connect the Battery, nothing changes.

Dear All, Could you please share us a technical document to show us what was the exat meaning of "N" letter of your part BAT54CNFILM-H/J ? Actually we ordered 6K pcs of your part BAT54CFILM from Digikey and its Digikey part number is 497-3786-2-ND but received this part as its part number was written as BAT54CNFILM-H/J on the manufacturer label of this part and our customer needs to learn what is the meaning of "N" letter on this part number. So please provide us a document to explain this "N" letter as this informations is not available neither in digikey nor in its datasheet

HelloI am currently developing an AC switch for a heating boiler in a coffee machine.The boiler has a power rating of approx. 1200W.  To control the boiler, I have opted for a triac circuit (T1250H-6I) with an optotriac (14230634300) and ZCC. I used Application Note AN5114 to size the resistors. The description is generally excellent. However, I have a question regarding the voltage ripple on the triac. The note recommends a value of 4V. I cannot achieve this value with the standard resistor values available. My calculations give a voltage ripple of approx. 25V. Is that too much? Or what can I do to get down to the recommended value of 4V, triac with lower Igt?Best regardsJohn 

Hi,    I bought VIPER06LN from mouser. Please help me check the COD. The Chinese custom need this information.   Thank you

Hey!Does anyone recognice this part?It`s marked with C306 (ST- Sign) FRO169.It looks like a transistor or diode in SOT-229 package.Thanks!Frank

Hi I plan on using STWBC86 for a wireless charger prototype. I was looking at the datasheet for the reference designs and found that the reference schematics has missing or has hard to read values, labels, and wires. Is there a better version of the schematics that is clear and completed? If there is not, can anyone give recommendations for the highlighted parts?I have also attached the original Schematic as a PDF below so you can see the clean version as well.

I think this is diode. I have search on all internet but cant find correct. :) Thanks  Best Regards  Fredrik

Hello There, Where can I find the example code for interfacing L9305 through SPI? Please suggest some sample Code.  

From Figure 12.STEF033 cannot be used for the case Ilim=1A?Rlimit is valid when the value is more than 120 ohm?

Hi I have a question regarding use of STL6P3LLH6 MOSFET in the reference design as shown in EVAL-SCS001V1. In this reference, there is only one STL6P3LLH6(T1) used as shown below:   But in the datasheet of STUSB4500, Fig 10 shows use of 2 such MOSFETs as shown below. What is the advantage of using 2 of these? In my design, i will use STUSB4500 to negotiate only fixed 20V, 2.5A. So, wondering if i need to put 2 MOSFETs or would it be OK with only one?Thanks!