TPS63001: TPS63001 switching frequency

June 18, 2019, 5:02 am

≫ Next: UCC27519: No output when Vdd is 5.5V and In+ is 3V square wave

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Part Number:TPS63001

Dear Sir or Madame,

I'm designing a PS using TPS63001 and currently calculating the Ipeak of the inductor according to the datasheet (DS) - TPS63001 rev. C (slvs4520c), section 8.2.2.2 Inductor selection.

On page 12 you provide the necessary formulas as well as 'f = Converter switching frequency (typical 2.5 MHz)'. However the oscillator range for this part is 1250 - 1500 kHz (6.5 Electrical Characteristics, page5), which I would consider being the switching frequency (during fixed frequency operation). [Note that if you take a look at TPS63031, the same 'typical 2.5 MHz' is stated in section 9.2.2.2 Inductor selection, but this part actually has the oscillator frequency range of 2200 - 2600 MHz.]

Therefore I would like to ask what is the switching frequency of TPS63001? Is there a mistake in the DS or is my understanding incorrect?

Thank you

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UCC27519: No output when Vdd is 5.5V and In+ is 3V square wave

June 18, 2019, 5:18 am

≫ Next: LM5022: Multi phase design for LM5022 controller

≪ Previous: TPS63001: TPS63001 switching frequency

Part Number:UCC27519

Can you help, we are using UCC27519, when VDD = 5V and IN+ is 3V square wave the device work correctly.

However when increase the VDD to 5.5V, In+ the same is 3V, there is no output, does this match the spec? thanks!

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LM5022: Multi phase design for LM5022 controller

June 18, 2019, 5:24 am

≫ Next: TPS2546: 1.5A power out only and no USB communication requirement

≪ Previous: UCC27519: No output when Vdd is 5.5V and In+ is 3V square wave

Part Number:LM5022

Hello, do you have any suggestions on how to make a multi-phase, interleaved boost controller using this device?

I am looking into a way to share equally the currents between the legs

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TPS2546: 1.5A power out only and no USB communication requirement

June 18, 2019, 5:45 am

≫ Next: BQ34Z100EVM: Cannot seal - stuck in unsealed state

≪ Previous: LM5022: Multi phase design for LM5022 controller

Part Number:TPS2546

Hi Team,

We want to use TPS2546 to do BC1.2.

1.5A power out only and no USB communication requirement.

Please kindly help to confirm.

What mode should we select?

Is below schematic OK?

Thanks

↧

BQ34Z100EVM: Cannot seal - stuck in unsealed state

June 18, 2019, 3:49 am

≫ Next: UCC27531: Output is always LOW irrespective of enable and input. We would like to know the reason for this issue

≪ Previous: TPS2546: 1.5A power out only and no USB communication requirement

Part Number:BQ34Z100EVM

I have been successfully using the BQ34Z100EVM for several weeks now, and was able to transfer between sealed, unsealed and full access modes. However, recently I have found that the device refuses to transition away from an unsealed state. Strangely, after a power cycle or reset the chip defaults to a sealed state, as expected, and I am able to transition to an unsealed state with no problem, indicating that the access keys for this are correct. However, when I try to return to a sealed state using the control sub-command 0020h, it refuses to do so.

I am also unable to transition to full access mode, although I am sure that the default key (FFFFFFFFh) has not been changed. I have tested this with both my own microcontroller code and with the Battery Management Studio with the same results. All other device functions are functional, such as reading/writing flash locations.

Does anyone have any idea why this is happening?

↧

UCC27531: Output is always LOW irrespective of enable and input. We would like to know the reason for this issue

June 18, 2019, 5:06 am

≫ Next: EM1402EVM: MIBSPI communication for Active cell balancing

≪ Previous: BQ34Z100EVM: Cannot seal - stuck in unsealed state

Part Number:UCC27531

UCC27531DBVT - Output is always LOW irrespective of enable and input. We would like to know the reason for this issue.

Circuit Diagram:

Supply voltage=15V, Both enable and input pin are controlled by FPGA (5V). It has been tested successfully for long period of time (ie.,operating hours=8hours/day, total working day =30days(approx)). But suddenly IC got failed now (Note: No changes done in circuit /setup). Total nos of failed IC is 2. I don't know why it was failed. Can you pls help us to find the root cause for this problem?

For info : Zener part # : BZT52C15-7-F, MOSFET part number : IPB60R199CP

Pulse ON/OFF time : 1us /1.7ms

We have taken some measurements from failed ICs for your information.

Test Results are given below,

Supply voltage:15V, Drawn current : 25mA (Without any input at enable and input pin).

Note: We have measured the output impedance for 2 failed ICs.

Failed IC Nos	Pins
Failed IC Nos	Enable	Input	OUTH (Imp measured W.r.t Supply Pin	OUTL (Imp measured W.r.t Gnd Pin
1	High	High	Short	Open
1	Low	Low	Short	Short
2	Low	Low	Short	Open
2	High	High	Short	Short

Impedance measured to every pin w.r.t gnd without giving the supply to both ICs.

Pin No	Impedance
1	open
2	222k
3	1.065meg
5	0.937meg
6	2.6meg

↧

EM1402EVM: MIBSPI communication for Active cell balancing

June 18, 2019, 6:02 am

≫ Next: TL5001A-Q1: can take 12v@ 22 A output from 8 to 40 v input using tl5001a-q1?

≪ Previous: UCC27531: Output is always LOW irrespective of enable and input. We would like to know the reason for this issue

Part Number:EM1402EVM

Hi,

i am doing active cell balancing in TMS570LS3137. the example code available is working on the evaluation board with SPI communication. now, i want to implement it through MIBSPI not with SPI.

while debugging, the code getting struck in the following:

g_ui32EMB1428Status = spiTransferByte(mibspiREG1, (EMB_COMMAND<<4));

if((g_ui32EMB1428Status &(0xF0)) != 0xA0)//done =high, enable=low
{
while (1);
}

and g_ui32EMB1428Status value is 0xD8.

i am attaching my halcogen file with code. kindly review it and please let me know if any configuration setting, i am doing wrong.

(Please visit the site to view this file)

Thanks in advance,

Regards,

Gargi Pancholi

↧

TL5001A-Q1: can take 12v@ 22 A output from 8 to 40 v input using tl5001a-q1?

June 18, 2019, 6:13 am

≫ Next: TPS2540EVM-623: USB Connector Spec on Eval Board

≪ Previous: EM1402EVM: MIBSPI communication for Active cell balancing

Part Number:TL5001A-Q1

Hi,

We required 12 v 22 A output from the 8 to 40 v input. Can i select the tl5001a-q1 IC for this application?

If this IC is not suitable, Please suggest any other best buck boost regulator supporting up to 22 A output. with high efficiency.

↧

TPS2540EVM-623: USB Connector Spec on Eval Board

June 18, 2019, 6:37 am

≫ Next: LM66100: RPP in dual diode ORing application

≪ Previous: TL5001A-Q1: can take 12v@ 22 A output from 8 to 40 v input using tl5001a-q1?

Part Number:TPS2540EVM-623

Hello,

I am currently designing a board to have the capability of charging a Samsung Tablet about 100% of the time. I checked your eval board USB connector and it looks like it is rated at 1 Amp, however your board data sheet details a max of 2800 mA (2.8A) of current for downstream charging. Is there something I am missing or is the current going to be limited to 1A for charging? It seems like the connector shouldn't be able to hand more than 1A max. Also is the TPS2540 tested with Samsung tablets? If I plan to use Ipad or Samsung Tablets is the TPS2540 part interchangable with either tablet?

Thanks,

Mike

↧

LM66100: RPP in dual diode ORing application

June 18, 2019, 6:55 am

≫ Next: TPS62736: Resistor Network

≪ Previous: TPS2540EVM-623: USB Connector Spec on Eval Board

Part Number:LM66100

Section 9.2.2.1 of the 2019 datasheet mentions using a series resistor on the CE/ pin to limit the current into CE/ during a negative voltage event. What is an acceptable current to allow, or what value resistor should I use?

↧

TPS62736: Resistor Network

June 18, 2019, 7:06 am

≫ Next: TPS54340B: TPS54340 vs TPS54340B

≪ Previous: LM66100: RPP in dual diode ORing application

Part Number:TPS62736

Team,

I plan to use the 4 resistor network (with VIN_OK pulled to VIN to disable) and need to know how critical the 13MOhm sum is to the operation of the circuit. Being size constrained I want to use 2ea. 0201 resistors for this purpose and 6.xMOhm 1% resistors are very difficult to source. If the series resistors sum to 1MOhm for example, does this adversely impact the operation of the TPS62736?

Thank you.

↧

TPS54340B: TPS54340 vs TPS54340B

June 18, 2019, 7:10 am

≫ Next: WEBENCH® Tools/LM25141: Simulate LM25141 with CSD86356Q5D

≪ Previous: TPS62736: Resistor Network

Part Number:TPS54340B

Hi Guys

What is the difference between TPS54340 and TPS54340B, B Version ?

On the Q1 post the answer was “They are functionally and parametrically equivalent.” and "B" version has fixes to the error amplifier to correct thermal issues."

Does this apply to the non Q1 devices as well?

Thanks

↧

WEBENCH® Tools/LM25141: Simulate LM25141 with CSD86356Q5D

June 18, 2019, 7:27 am

≫ Next: BQ3050: Meaning and function of the ICC bit of the BatteryMode Register

≪ Previous: TPS54340B: TPS54340 vs TPS54340B

Part Number:LM25141

Tool/software: WEBENCH® Design Tools

Hello

It is possible to simulate the LM25141 in combination with CSD86356Q5D Mosfet Array in the Webbench?

↧

BQ3050: Meaning and function of the ICC bit of the BatteryMode Register

June 18, 2019, 7:28 am

≫ Next: BQ24295: no USB cable detection

≪ Previous: WEBENCH® Tools/LM25141: Simulate LM25141 with CSD86356Q5D

Part Number:BQ3050

Hello,

Due to the lack of Information in the RTM about the meaning and the function of the ICC bit of the BatteryMode Register I would like you to answer us the following questions:

1) In page 74 says:

ICC: — This flag indicates if internal charge controller function is supported or not. This value is fixed to 1.

With the term internal charge controller does it mean the Smart Battery Charger function (see the ChgM bit of the BatteryMode Register in page 73)

or does it mean another function ?

2) Has the result of the ICC bit (0 or 1) during the lifetime of the Pack to do with the given values of ChgM and AM bits in the BatteryMode Register ?

I am asking because in our application althouth we gave the value 6081 in the Init Battery Mode Parameter sometimes we take as result ICC=0.

Could you please explain us the reason ?

Best regards,

Theo

↧

BQ24295: no USB cable detection

June 18, 2019, 7:35 am

≫ Next: BQ25895: With a resistor across D+/D- USB DCP will not negotiate to 3.25A as designed.

≪ Previous: BQ3050: Meaning and function of the ICC bit of the BatteryMode Register

Part Number:BQ24295

hi,

we have a situation with BQ24295 (return from the field).

sometimes under low battery voltage condition (aprox 3.3V), the BQ24295 switches off the Q4 FET (voltage at SYS pin is 0.3V).

Moreover, there is no reaction to USB cable insertion.

After disconnecting and reconnecting battery everything is working as expected, at least for some time.

We still could not reproduce problem in the lab (still trying).

What might be a potential root cause?

what we should look at?

In the attachment you can find register states.

We wonder if we could have accidently changed highlighted register states, that are undocumented (there is no information about them in datasheet).

thanks a lot in advance

Vincenzo

↧

BQ25895: With a resistor across D+/D- USB DCP will not negotiate to 3.25A as designed.

June 18, 2019, 7:41 am

≫ Next: BQ25895: BQ25895 schematic review

≪ Previous: BQ24295: no USB cable detection

Part Number:BQ25895

With R426 across D+/D-, I thought the BQ25895 would negotiate to USB DCP = 3.25A. Therefore, the input current would be the lower of I2C or the ILIM pin and that is 2A (ILIM pin). Why is that not occurring?

-Jeff

↧

BQ25895: BQ25895 schematic review

June 18, 2019, 8:27 am

≫ Next: TLV1117: ESR of output capacitor

≪ Previous: BQ25895: With a resistor across D+/D- USB DCP will not negotiate to 3.25A as designed.

Part Number:BQ25895

Hi all,

Would you please help review schematic of BQ25895? Especially the OTG function, thanks.

↧

TLV1117: ESR of output capacitor

June 18, 2019, 8:29 am

≫ Next: BQ40Z50-R2: connecting 2 x 3s1p in parallel for redundancy/monitoring

≪ Previous: BQ25895: BQ25895 schematic review

Part Number:TLV1117

Hi team,

In the TLV1117 datasheet show that:

The TLV1117 device is designed to be stable with tantalum and aluminum electrolytic output capacitors having
an ESR between 0.2 Ω and 10 Ω.

Could you give more comments why the ESR should be in the rang of 0.2ohm to 10ohm? is there have equation to calculate the ESR value?

how to affect the LDO work If the ESR of output capacitor higher than 10 ohm or lower than 0.2ohm?

thank you

↧

BQ40Z50-R2: connecting 2 x 3s1p in parallel for redundancy/monitoring

June 18, 2019, 9:38 am

≫ Next: TPS74801: efficiency

≪ Previous: TLV1117: ESR of output capacitor

Part Number:BQ40Z50-R2

Hi, I am currently working on a charger/batterypack for use with a portable measurement solution.

I have drawn heavily from the pmp40441 reference design as I have based the charger off of the BQ25713.

I am modifying this design to include a small lcd display for diagnostic info (cell voltages, charge current, etc...)

Thinking of using the BQ40Z50-R2 for the battery monitoring side of things and here is where my confusion begins.

I am using custom battery packs consisting of INR1860-E35 (samsung 18650 3500mAh) in a 3s1p configuration,

using the BQ40Z50-R2 as the monitor/gauge will give me the diagnostic data I want, but not the capacity I need.

We have gone with 18650's as the main cells because this particular system is portable, and downtime is costly,

we needed something that was high capacity, rechargeable, and available on short notice.

I know I could simply make a 3s2p pack using one BQ40Z50-R2 and I would get the capacity I want and be able to read the (3) cell voltages from the pack.

The issue here is I want redundancy and also the ability to monitor every (6) cell individually. I'm confused about how to get this to work with my current setup.

I know I need to use some kind of power ORing to isolate the packs from each other, but how do I go about getting this to work?

These packs will be installed and calibrated at manufacture, so I don't foresee too much of an imbalance between packs, but I need assurances that if cells in one of the packs is replaced and the new cells are at a different charge than the other pack the system can handle this. Can 2 x 3s1p be placed in parallel utilizing 2 BQ40Z50-R2 as individual pack controllers, can the voltages on both packs be different and still charge/discharge the way the system expects? How do I go about achieving something like this or better-I am open to ideas.

Also