Part Number:LP5523
Hello,
I designed in a .47uF, 6.3V rated cap into C1/C2, instead of the recommended .47uF, 10V from the datasheet.
I'm not able to find a 10V rated cap in the same package size and I'm not able to have additional design changes.
Therefore I'm looking into how the 6.3V rated caps will impact the design. Will you please help to advise?
Thanks!
Part Number:TPS54425EVM-608
Hello,
I am working with the EVM and there were no pads included to place a small resistor in the control loop to test for stability via a gain/phase analyzer.
So I soldered on the resistors in a way that may have led to a bad connection. after plugging it in and powering up, I noticed the output voltage and current drop to 0V and discovered that the input of the inductor was shorted to ground via a continuity test.
After replacing the inductor and fixing the control loop connection, everything was functional again.
what could have happened? did the inductor exceed its maximum rating?
thanks,
Kevin
Part Number:TPS7A10
Hi Support Team
Can you confirm that the GLOBAL UVLO will activate tactive discharge circuitry in the "p" version?
Customer wants this to trip if the voltage starts to fall.
Thanks
Jeff Coletti
Part Number:BQ27520EVM
Hi,
I have been recently working on configuring a bq27520 chip in a project I am working on. I have been using the EVM to run chemical ID tests and learning cycle tests in an effort to generate a golden binary for programming the fuel gauge with prior to deploying it in an embedded system.
I was able to run several successful chemical ID tests. I decided on the ID 3171. From here, I ran a complete learning cycle that failed. About 1 day later I ran another learning cycle that got "successful" results. I saw that Data Memory-->Gas Gauging-->State-->Update Status 1: changed to 0x02.
I also saw that data memory Ra1 Table had been updated. Although the other "update status" was 0x02, the Data Memory-->RaTables-->Ra1 Table--> Ra Status was 0x05 at the end of the run. Should this be considered a successful learning cycle? The Ra0 table that had been updated during the first "failed" cycle status (Data Memory-->Ra Tables--> Ra0 Table --> Ra Status) changed to 0.
There is also another "update status" in the Data Memory-->OCV Tables-->OCVa0 Table-->Update Status and OCVa1 Table-->Update Status. These values seemed to be at 0x00 the whole time.
I have read that I am supposed to "copy the table that has the learned, ie the qmax and Ra values to the one that are unlearned so both tables will now have the same values" in preparation for creating a golden binary (slua902). Does this mean I am supposed to copy the Ra1 Table (including Ra Status, Ra Flag, Ra Base, and Ra Gain) to every single one of the Ra Tables: Ra0 Default, Ra1 Default, Ra0 Table, Ra1 Table, Ra0x Table, Ta1x Table? It is a little unclear due to their being 6 tables and instead of the implied 2.
Also, do I copy Data Memory-->Gas Gauging--> State --> Qmax Cell1 to Data Memory-->OCV Tables-->OCVa[0/1]-->Qmax Cell?
I am attaching my log file from the run as well as the exported settings before and after the learning cycle.
Thanks for the help,
Eddie
Part Number:LM5176
I used WEBENCH to design a boost-buck converter based on LM5176. Input range 11-50V, output 24V @8A. For the two boot diodes, the tool selected components that seem oversized: SBRD10200TR (200V, 10A) and B260A-13-F (60V, 2A).
Am I missing something? Quick back of the envelope calculations based on gate charge and switching frequency suggest that a much smaller, 250mA diode like BAS316,115 would be sufficient.
Thanks!
Bart
Part Number:LM74700-Q1
Hi, Team,
Is it possible to use LM74700-Q1 as diode for parallel battery protection? A customer is using 1S battery in parallel with diode protection.
Best Regards,
Satoshi Yone
Part Number:UCC28070
Hi John-san & team,
Our customer is now considering to design their product with similar schematic to 1401.Sch-1.pdf(TIDA-0130).
Please allow us to ask you some questions about a resistive current sensing method as below,
1.
They are struggling to select OP-Amp for sensing current.
Could you let us know how to determine the specifications(BW, SR ...) of amplifier?
John-san mentioned in the related Q&A as below,
"For example if your switching frequency is 100kHz then you can expect to be required to detect pulse widths of 1uS or so."
but do you have any calculating formula to lead the spec of amplifier properly?
2.
They found the degradation of power factor in case of using lower-speed amplifier for sensing current.
Do you have any other concerns with using lower-speed amplifier except for power factor?
3.
Please give us the detailed explanation that why degraded power factor in above case.
4.
We infer that the downslope of inductor current during the switching period OFF-time is synthesized by the input of VINAC and VSENSE pin.
Are there any concerns to the quality of the synthesized waveform of OFF-time due to the degradations of the input waveform to CSA/CSB-pin during ON-time?
Best regards,
Satoshi
Part Number:TPS659037
Hi all
Would you mind if we ask TPS659037?
We would like to know the operation in case of GND short at any SMPSXs.
<Question1>
After short occurs, will the DCDC(SMPSx) be auto retry or latch off?
<Question2>
How much is the deglitch time?
There is the description on the datasheet
"The time between a short detection and a SMPS switch-off is approximately 155 µs to 185 µs.
This same behavior applies to LDO shorts using the LDO_SHORT_STATUS registers."
155us to 185us?
<Question3>
Does the device sense OCP condition at high side FET?
So, are thereshold level "ILIM HS FET" on the datasheet?
Kind regards,
Hirotaka Matsumoto
Part Number:UCC28070
Hi team,
We can see the description about PKLMT as below in the datasheet of UCC8070A,
Page-8 [Electrical Characteristics]
Peak current limit threshold: 3.27V (Min.), 3.3V (Typ.), 3.33V (Max.)
Page-20 [7.3.9 Programmable Peak Current Limit]
"The programming range of the PKLMT voltage extends to upwards of 4 V to permit the full use of the 3-V average current sense signal range; however, note that the linearity of the current amplifiers begins to compress above 3.6 V."
Is my understandings as below correct?
-> UCC28070A has the capability of PKLMT to accept 4V, but the recommendation is 3.3V(Typ.) because the linearity is gradually degrading above 3.6V.
Best regards,
Satoshi
Part Number:TPS61169
Hi,
Part Number:TPS65381A-Q1
Hi Scott,
This is additional question.
I understood from answer to previous post that WD_RST_EN needs to be cleared as soon as possible in MCU boot process.
Customer observed the 2nd WDT reset (a reset generated after a WDT reset) is generated in ~21ms after reset regardless WDT configurations.
For example, even WDT is configured to generate reset in 18msec, the 2nd WDT reset is generated in ~21msec.
Even if WDT is configured to generate reset in 9msec, the 2nd WDT reset is generated in ~21msec.
The ~21msec seems to be the time needed to complete BIST.
Does this means WDT counter is frozen during BIST?
And MCU cannot access SPI during BIST, so clearing WD_RST_EN is not possible during BIST period, correct?
If so, when MCU should access SPI to clear WD_RST_EN to avoid unwanted WDT reset?
Thanks and regards,
Koichiro Tashiro
Hi team,
My customer changed current sense resistor R3 in BQ2000EVM to 0.1 Ohm and expected to have 0.5A chare current.
According to a datasheet Eq. 4 current should be 0.05 / 0.1 = 0.5 A.
But really they have around 300mA charge current.
What can be reason of such low current?
Part Number:TPS62742
Hi Experts,
I have used TPS62742 for a battery operated application. What I notice is that the input and output voltage drops significantly when the load current rises above 40 - 50mA. Ideally, it should support up to 400mA current. Below is the snapshot of the circuit for power supply.
Inductor Used: LQM21PN2R2MCAD (which is rated for 1A)
Note: I have already tried placing 0Ohm instead of R5, R6 and R79, still getting the same results.
There's one mistake in power good pin - so I have removed power good resistor R78, hope that should not be causing any issues! I do not want to monitor power good.
Regards,
Rahul
Part Number:UCD3138
Hello everyone,
I'm developing my application using LLC Firmware. I faced an unknown “on” condition on DPWM2A signal while burst mode is active. This condition is occured inside my hiccup mode which has transition to idle state, wait a while and go to regulated state.
If I disable burst mode on DPWM3A, this unknown on situation disappeared. I believe that this is because DPWM2A falling edge is derived from DPWM3A falling edge wih EDGEGEN feature but if DPWM3A signal is not valid (because of BURST Mode) DPWM2A is not falling to 0.
Is that comment true? what will be the side effects if I changed DPWM3 burst enable bit to disable. (DPWM3 burst mode is enabled by default on original firmware)
Best,
Part Number:UC2524A
Hello guys,
One of my customers is looking for any document or application note that CL+,CL- terminal usage can be known because they don't know well how to connect CL+,CL- terminals of UC2524A.
Do you have any document which has whole schematic using UC2524A?
Your reply would be much appreciated.
Best regards,
Kazuya Nakai.
Part Number:BQ24070
Hi
I am currently working on BQ24070RHLR single cell lithium ion charging IC in our application.
I am facing some problem. They are listed below.
1. Charge current won't exceed 450mA.
2. No indication of charge cutoff in IC.
3. Even battery is not connected still IC shows charging indication.
I am attached a screenshot of our circuit we are currently working on. Please review and suggest some changes if needed.
In brief we need charge current of 1.5A and we are using 5V 2-A AC adapter. We designed circuit for getting same output response.
