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UCD9248: Capacitor setting in fusion digital power designer

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Part Number:UCD9248

In the design tab of the fusion digital power designer, one should set each capacitor's value. For example, if the rail contains 10 capacitors, the position of feedback of voltage is between the first capacitor and second capacitor, should I ignore the other 9 capacitors and only enter the value of first capacitor? 

If in my design the output of rail is filtered by pi filter, should I enter the value of inductance? If so how can I enter the value of inductance?

  


BQ51013B: Problem while startup, pulsing 2s/0.5Hz no output voltage

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Part Number:BQ51013B

Hello together,

Im new comer to TI's wireless charging chips.
I use a self designed board with the  BQ51013B and a custom coil.

C1 and C2 capacitors are calculated as described in datasheet but I dont get it working!
Im using an official TX-Charger but I get absolutly no Output Voltage on the Output pin.
On the RECT pin I can measure a pulsing ~6.5V with 0.5Hz (Beacon?), see attached screenshot from oscilloscope.

Do you have any advice, what I can improve in my circuit to get it working?

Thanks in advance! 

BQ40Z60: bq40z60 very little charging current

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Part Number:BQ40Z60

Hello TI team,

After getting a 4S1P battery, powering my custom PCB with a 24V power supply and clicking the charge enable button, the current of the PSU changes from 13mA to 22mA. I expected greater charging current, but after spending some days, I did not get anything,

I attach a screen shot of bqstudio and gg file. What can I do to increase charge current?

Kind Regards,

       Carlos

BQ25570: BQ25570 Schematic review and design tips for super low power system

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Part Number:BQ25570

Hello charger folks,

      My customer is designing a solar related products, they have finished the BQ25570 schematic. please help to review the schematic then give your valuable comments. Thanks!

TPS54620: TPS54620 thermal resistor

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Part Number:TPS54620

Hi,

could you help to confirm Why RθJC(top) bigger than RθJA in datasheet of TPS54620

Best Regards,

Mark

LM25118: LM25118

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Part Number:LM25118

I am starting a design based on LM25118 and have the following questions

1 > I have space limitation and want to use Ceramic caps in inputs and outputs 

2 > it is a processor programmable output from  10V to 27V

3 > Input voltage is 18V to 33V

4 > hi output current up to 9 Amps

Is this the correct part to use any other suggestion would be appreciated 

TINA/Spice/LMR62014: Help simulating phase margin with TINA

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Part Number:LMR62014

Tool/software:TINA-TI or Spice Models

Hello,

I've managed to get the tina schematic for the LMR62014 up and running, but I"m lost as to how to simulate my gain and phase margin.  Could anyone point me in the right direction?  The circuit seems to be working and the transient analysis shows the supply powering up.  I've attached my circuit.  (Please visit the site to view this file)

LM5155: Excel Quick Start Calculator (MOSFET Losses calculation)

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Part Number:LM5155

Hello,

The datasheet and design guide provide some equation to estimate power losses of the MOSFET. Regarding Excel Quick Start Calculator, the parameters to enter are different (Qgd, Qgs, Rg, Gfs, ...). It seems that Rg has a big impact on the MOSFET Power losse in your Excel sheet. Could you provide the equation you use? 

Thank you,

JMB


UCC29950: Power management forum

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Part Number:UCC29950

Hello.

I'm trying to make 300W AC/DC converter with using ucc29950.
My schematic made according directions from datasheet (pages 36-37). I connected SUFS pin to VCC voltage. VBULK, AC1 and AC2 line resistances are in allowed range. I applied 110V AC Voltage to the input of the schematic, but there wasn't any voltage at PFC_GD pin. When I tried 220V AC, there still wasn't any signal.

At 110V AC there is such voltages at the pins:
1 - GND - 0
2 - GD2 - 0
3 - VCC - 13,2V
4 - SUFG - 0
5 - SUFS - 13,2V
6 - AGND - 0
7 - PS_ON/MD_SEL - 6,8V
8 - VBULK - 520mV
9 - AC2 - 1,04V peak
10 - AC1 - 1,04V peak
11 - LLC_CS - 0
12 - FB - 0
13 - PFC_CS - 0
14 - GD1 - 0
15 - AC_DET - 0
16 - PFC_GD - 0

Could you please help me to resolve that problem?  Where am I wrong?
In addition, it will help me a lot if you write pins voltages at normal operation.

TPS544B20: Internal capacitance value of PGOOD

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Part Number:TPS544B20

Hi Experts,

I would like to know the internal capacitance value of PGOOD. Would you tell it, please? My customer want to know it.

Best Regards,
Fujiwara

TPS2121: Could you provide TPS2121 CP2 pin absolute maximum rating?

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Part Number:TPS2121

Hi 

We cannot find out CP2 rating in ther datasheet.

Could you help to provide?

BQ24640: Charging Problem

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Part Number:BQ24640

When the super capacitor charge is not intermittent, and STAT-turns on / PG-turns on even when charging is not possible.
Figure 11. Typical Application Schematic of Datasheets

Changes in the reference circuit

Input voltage (Adapter): 19V -> 12V

Output voltage (Super Capacitor): 8.1V-> 10.5V (R1: 105K-> 175K, R2: 300K-> 470K)
1. I was wondering if the input voltage is too low compared to the charging voltage, which is causing the problem.
    Is there a problem with the output voltage versus the input voltage I designed?
2. Why is it not charging intermittently?

UCC28070A: Request

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Part Number:UCC28070A

Hi

I'm testing Bridge-less circuit by UCC28070A.

Please let me know why the  circled check of the PFC MOSFET waveform.

Test Condition

Input: AC 90V

Output: DC 390V 1.3A(About 500W)

Thanks & Best Regards

TPS53353: TPS53353: Qustion of Data Sheet

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Part Number:TPS53353

HI everybody!
I have a question about the TPS53353 datasheet.

datasheet:SLUSAK2C.pdf page4

6 Specifications
6.1 Absolute Maximum Ratings
Output voltage range: GND :  –0.3V min. +0.3V max.

What is this mean?
Is this Typo?
What is true?

Remarks:
"TPS53353" has only GND(ThermalPad) Pin.
I don't think of the difference between AGND and PGND.

Please let me know if you have any information!

Best Regards
Shing

LM5161: Vo delay setting

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Part Number:LM5161

My customer use the LM5161 and want to adjust the output voltage later than the input voltage for more than 1 sec, what is the method?

Circuit as follows:


BQ76PL455A: VP pin connection

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Part Number:BQ76PL455A

On the datasheet Pin functions, VP requires a 0.1µF capacitor to AGND and a 4.7µF capacitor in series with a 0.390 ohm resistor to GND.

However I think there is no 0.1uF capacitor in datasheet schematic or EVM schematic. There is only 4.7uF capacitor in series with a 0.39 ohm.

Is it needed 0.1uF capacitor?

Best Regards
Kohei Sasaki

TPS2549: When I charge 2.1A using TPS2549

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Part Number:TPS2549

divider  seems to be included in DCP mode than a data sheet P24. In a 2.1A dispatching of load, can  TPS2549 perform a data communication?

BQ76940: schematic review help

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Part Number:BQ76940

Dear TI Experts,

My customer is designed BQ76940 in their project, they find that 0.3% of BQ76940 are broken after all the manufacture process. The phenomenon is impedance between VC0 and GND very small while normal chips are huge. They suspect ESD cause this but they can't find  Could you kindly help to review the attached design and give some advices? Thanks a lot.

(Please visit the site to view this file)

LM3450: LM3450 Dimmer

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Part Number:LM3450

Hi Team,

I have the LM3450AEV120V30 kit, I have a question about that controller:

The Holding current mechanism is the bleeding circuit that sink current from the Dimmer to maintain proper work with Dimmers.

The disadvantage with the bleeder, is efficiency+PF+THD reduces,

When the dimmer in not present, the Bleeding in the LM3450 is still working even though it is not needed (I checked in the EVAL board).

I have a MCU that can detect when the Dimmer in Present or not. I would appreciate to get recommendation how the MCU can disable the Bleeding circuit in the LM3450?

Thanks,

Shlomi

 

TPS2378: When HDMI is inserted first, the TPS2378 is not powered.

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Part Number:TPS2378

1When RJ45 is inserted first,and then HDMI inserted, the TPS2378 is  powered OK.

2When RJ45 is inserted first,and then Oscilloscope'GND inserted, the TPS2378 is  powered OK.

3When HDMI is inserted first, and then HDMI inserted,the TPS2378 is not powered.

4When Oscilloscope'GND is inserted first,and then RJ45 inserted, the TPS2378 is  powered OK.

We used the TPS2378+MP9928(DC-DC) to design.We believe that the external ground line (HDMI/Oscilloscope) interferes with the detection of the TPS2378, but our DC-DC is not isolated. Is there any way to solve this problem?

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