Hello Feng, Yes, there are a lot of methods to change the start-up behavior. However before that Can they look at the inductor current. Again, this is a peak current regulated LED driver, it should not overshoot. If the current ripple is constant it should not overshoot. Have they verified it is overshooting? Best Regards,
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Forum post: RE: LM3409: Overshoot of light power measurement after load current transient
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Forum post: RE: TPS61196: VIFBV and R10 selection
Hi Amelie, For 102mA per channel, from the figure 5, the recommend minimum headroom voltage is about 300mV. Anf refer to equation 4, R10=VIBF*R11/307.3=300*49.9/307.3kohm. Regards Sean
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Forum post: RE: BQ78350-R1: RSOC calculation
Hi Parimala, When the BQ78350-R1 comes out of reset, it initially estimates the RSOC based on the ChemID that you have selected for your battery. Each battery has a different voltage curve. Please make sure to follow all of the steps in the Using the BQ78350-R1 app note, specifically the Gas Gauging section. You need to load the correct ChemID into the device and go through the process for setting the CEDV parameters for accurate gauging. Also make sure to read through Chapter 9 of the BQ78350-R1 Technical Reference Manual - this chapter explains the gauging in detail. There is a section that describes initial Battery Capacity at device Reset. Best regards, Matt
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Forum post: LM5085: lm5085 design doesn't work properly
Part Number: LM5085 hi, I've a problem, I need a supply with programmable current limit. I've chosen for the LM5085 because it has that function built in. The problem though is that the current limit doesn't work in my design and I have no idea why. I have read the whole data sheet multiple times, but I don't have a clue why this doesn't work.
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Forum post: RE: TPS2388: Misjudgment PD plug in
Hi Thomas, Yes, it's the same case. Please kindly help with it. Thanks! Best regards, Jamie
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Forum post: RE: BQ78Z100: Wrong register readings
Hi Kang, Customer has an additional request, please see below: "We need to read raw data of State of health register of bq78z100 directly. Actually our EV2400 kit reads the register directly and present at bqStudio. However we should handle this operation in our device. So, could you provide Linux command utility performing I2C read operation for our fuel gauge(bq78z100)?" Could you please help on this as well? Best Regards, Caglar
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Forum post: RE: LMZM23601: DC-DC Step-up, MicroSiP™ (10) 3.80 mm × 3.00 mm package
hi Jimmy; thanks for your replay. i'm looking something pin to pin compatible and Vout adjustable (max 9V) boost with LMZM23601, i have very limited space on the PCB and LMZM23601 fits perfect. it will be grate if I had a boost with the same footprint. have we any chance TI produce this kind of component? best regards Shahriyar
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Forum post: RE: BQ24171: BATDRV
Hi Nestor, Your idea sounds feasible. BATDRV only goes low (but not all the way to gnd) to turn on the switch when the voltage at VCC/ACN falls below the voltage at SRN. Otherwise it sits at the battery voltage. You can use it as a logic signal but will likely need to level shift it. Regards, Jeff
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Forum post: RE: TLV758P: tlv758p thermal resistance
Hi Sammi, Of these, the TLV758P has the best thermal performance for the SOT-23 package. This has a T JA 176.9C/W. With 1.5W of power dissipation, this is a 265.35C (1.5x176.9) rise above ambient. 1s is a long time for this condition and the LDO will definitely thermally shutdown. There is no SOT-23 LDO that can handle this. A better solution might be something like the TPS73701DRB which has a T JA of 49.5C/W which would yield a 74.25C rise above ambient. I hope this helps.
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Forum post: RE: TPS2388: Misjudgment PD plug in
OK Jamie. Thank you for the confirmation. I propose we work the issue on this thread as there is more information here. I will assign this post to Penny and close the other thread. Thanks,
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Forum post: RE: UCC25600: waveform, dead-time,
Hello Kwang, Thank you for the additional information and waveforms. In the UCC25600, Burst Mode is triggered when the switching frequency exceeds 350kHz. The waveform in figure (3) is at 250kHz when signs of high output ripple voltage appears in figure (4). That indicates that this is not a burst-mode issue, but some other instability or repetitive deviation. The huge ~14Hz ripple in figure (5) appears like the LLC controller is turning on and off, not simply oscillating or bursting. I think this indicates a bias power problem or something similar as the output load gets lighter. Please check the VCC and gate-drive waveforms of the UCC25600 under these conditions and good conditions. Also compare the GD1 and GD2 voltages to the Vgs voltages of the high and low MOSFETs. (You will need an isolated differential probe for the high-side Vgs measurement.) Are you using a gate-drive transformer or some high-side gate-driver IC between the controller and the MOSFETs? Also check the VCC (or VDD) voltages and gate-drives of the SR MOSFETs, to be sure that they are operating properly. The SR Fets should not turn on too late or turn off too soon or double-pulse. Make sure that the bias voltages for all ICs, primary side and secondary side, remain above their respective under-voltage lock-out (UVLO) thresholds, so that they don’t turn off. Be sure to check that the secondary side regulator (that drives the feedback opto-coupler) receives the required minimum bias current or voltage that it needs to stay operating. Regards, Ulrich
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Forum post: RE: BQ76PL455A-Q1: ADC value suddenly all 0 for single scan
Hi Roger Vince has asked the same questions, but I'll answer them again. [quote user="Roger Hwang"]Is device sending all 0s?[/quote] Yes, the device is sending 0 for all ADC measurements. The header and CRC are non-zero. The CRC is correct for a response of all 0 values. [quote user="Roger Hwang"]Have you capture with logic analyzer?[/quote] Yes. All data I have provided thus far is captured using a logic analyzer while probing on the RX and TX lines near the MCU. [quote user="Roger Hwang"]May I ask what command you send on 0x02?[/quote] This is in the log file from my previous post. The TX packet from the MCU consists of: E1 02 07 10 94 0xE1 = Command frame, Broadcast with response, 8-bit address, 1-byte data size 0x02 = Register address: Command 0x07 = 000b (Synchronously sample channels) + 00111b (Address of highest module) 0x1094 = CRC [quote user="Roger Hwang"]Make sure you have same baud rate for all devices.[/quote] The baud rate is set to 250k for all devices (same as default). Only the lowest device is communicating over the single ended communication bus. There are no errors related to baud rate. As far as I can tell, there are no settings for the differential communication. [quote user="Roger Hwang"]CRC is generated by device and sends down to the base device.[/quote] This implies the highest module is actually reporting 0 for all ADC values and this is not a miscommunication between devices. Under what conditions might a module report 0 for all ADC values? Regards, Jason
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Forum post: RE: LM5145: LM5145 Application
Hi Iven, Could you provide the part number of integrated MOSFET solution? Thanks! Best regards, Jamie
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Forum post: RE: TPS2514: 5V/1A, 5V/2A charging solutions
Hi Emma, Here is one question want to confirm with you, in the datasheet 8.4 section, it says the "TPS2514 can automatically monitor the voltage of the USB data lines, and provide the correct electronic signatures on the data lines to charge compliant devices", How to understand the process? For example, one smartphone is connected to the port, what the process is to determine if it is 5W or 10W charging? Besides, in the datasheet 9.2, for the 5W and 10W application, the connection is different, my customer need support 5W and 10W with the same connection, could you please help check if TPS2546 is the right part to promote? My customer need USBA to Lighting/Micro USB line and support 5W and 10W charging, can TPS2546 be used? If yes, how to control the TPS2546 in such application? Thanks.
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Forum post: RE: TPS2388: Port detection issue
Chentsu, We will be closing this thread and working the issue via this thread which deals with the same end customer issue. https://e2e.ti.com/support/power-management/f/196/p/865425/3201897#3201897 Please continue to follow the discussion there and work with TIer Jamie Tseng to answer any questions Penny asks. It will help us resolve this for you quickly. Thank you for your local promotion of TI solutions,
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Forum post: RE: WEBENCH® Tools/UCC28C43: UCC28C43
Hi Mikhail, Thanks for the waveforms, From what we see voltage across Rsns resistor is zero when gate is high, although it should resemble primary current waveform(~ triangular). That means either current sense resistor is "short" or there is no transformer primary current flowing in the circuit. Can you check these 2 things: a. Measure transformer primary current(between points A. and B. , from the attached snapshot) b. Check if current sense resistor Rsns is working properly( not shorted, etc) sahil
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Forum post: RE: LM74610-Q1: LM74610QDGKRQ1 UL flammability rating
Hi Emiliano, Unless stated otherwise on the datasheet, all encapsulating materials used in TI semiconductor products meet the requirements of UL 94 flame classification V-0. Further, I’ve confirmed that the LM74610QDGKRQ1 device’s mold compound conforms to the Class V-0 Standard. I believe this has answered your question, if yes, click "this resolved my issue button" at the end of the thread. Regards, Kari.
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Forum post: RE: LM5050-1: LM5050-1
Hi Farzaneh, Yes, for 10A we need to go with MOSFETs external. Let me get back in detail next week, if that is okay. If you need a speedy response let us know. Regards, Kari.
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Forum post: RE: LM5050-1-Q1: MOSFET selection for up to 40 A current
Hi I acknowlege your response and would need more time to get back for the above questions. Is next week okay with you? Let us know if you need a speedy response. Regards, Kari.
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Forum post: RE: BQ25898D: About VSYS voltage
Hi, For 2, regardless of VBUS applied or not, the charger is in BATOVP so the buck converter is off and BATFET is fully on to discharge the overcharged battery. VSYS=VBAT - IBATdischarge*RdsONQ4. For 1, without a battery attached, V(SYS) depends on whether charge is enabled or not (/CE pin low or high) and whether the battery is above VSYS(MIN) or not. If charge is enabled, then SYS toggles between VSYS(MIN) (3.5V default)+50mV and VBATREG=4.2V+52mV max as the capacitor on BAT pin quickly charges and discharges. If charge is disabled and V(BAT)>VSYS(MIN), then V(SYS)=V(BAT)=52mV max but if V(BAT)<VSYS(MIN), then V(SYS)=VSYS(MIN)=3.5V+250mV. Regards, Jeff
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