Part Number:UC2526A
The datasheet for UC2526A does not explain how the current sense feature works. I am experience an issue where my PWM output is disabled at a constant period for a constant time and I suspect its the current sense, though the datasheet does not explain how it works or what it does.
How does the current sense work?
Part Number:LM5170-Q1
Hello,
I have a prototype board that has 4 LM5170 controller ships on it to regulate 4 independent sources onto one common bus that can source and sink current. I have 7 boards total and I am having trouble with one converter on 3 of the 7 boards. The one converter doesn't seem to want to go into buck mode when the DIR pin is set high. I have watched the SS pin during the transition and I see it cycle low and recharge. When I scope the FET's they are still cycling in boost mode for some reason. The other converters seem to respond correctly and as far as I can tell they are all build the same. When I check the ISET pin it is being commanded to the same voltage as a functioning converter. I have verified the DIR pin is set high, 3.3v. The converter seems to work just fine in the boost direction.
Another thing I noticed that seems off and may point to what I am doing wrong. The IOUT current relative to the LV current shifts going from boost mode to buck mode. Boost mode seems to track with what I would expect the LV current to be but buck mode, on the functioning converters, shifts to read significantly higher. I see the shift in the IOUT signal but the ISET signal still controls the same LV current that I would expect it to.
I am imagining there may be something in the layout or parts that is on the edge of a threshold but I don't know what to look at to figure out what it could be. Unfortunately the design is under NDA with my customer so I am not able to share the schematic or layout. If I could get any reason(s) why the converter would ignore the DIR command that I can look into it would be greatly appreciated.
Other notes for the setup:
VHigh: 24v-32v
VLow: 12v-16.5v
Switching freq: 150Khz - set and phase controlled from micro
Thanks!
Part Number:TPS3711
I am trying to possibly solve a problem with detecting a positive vs negative going DC input. The input path could have a voltage placed on it anywhere from 1V to 500VDC placed on it in either +/- direction. The circuit would determine if the voltage is + or - and select the correct window detector circuit (uses TPS3701) with a relay. My thought was to place a zener diode from ground to the input to prevent >6V, but in a forward zener bias situation, it could allow what would be too much negative voltage on the input (~0.7V). Have you tested if something like this would work, or do you know of a specific part that would be better suited for this type of application?
Part Number:UCC29002
Hi there,
I would like to parallel two isolated DC/DC module with 53 V input voltage, 28 V output voltage, 25 A output current capability by using UCC29002.
Besides remote sense pins (+Sense and -Sense), the products have an output voltage adjust pin (Vadj). This pin can be used to adjust the output voltage above or below output voltage initial setting by using an external resistor.
To increase the voltage the resistor should be connected between the Vadj pin and +Sense pin and to decrease the output voltage, the resistor should be connected between the Vadj pin and –Sense pin.
I'm just wondering how I should connect ADJ pin of the UCC29002 (pin 5)? Should I connect it to Vadj pin of the module?
Thank you very much in advance!
BR,
Ghasem
Part Number:BQ24770EVM-540
I've been working through the User's Guide with my bq24770EVM-540. I finally got it to communicate with bqStudio by switching the input USB port on my lab PC to a different port. I still have the following issues.
1.) After applying 19.5V to the input via PS#1, I still don't see the D5 LED (ACOK) lit, even though V(TP7 (ACDET)) = 2.59V
2.) When I measure V(J3(BAT, GND)), I measure 8.9V, but I should be measuring 1V +/-1.1V
All the other default parameters are measuring within correct range.
I am now able to read the Default Parameter Settings by clicking the "Read Register" button in bqStudio. I know correctly get the response “Device ACK OK” and the following readings:
Charge Option 0
EN_LWPWR is checked
WDTMR_ADJ is set at 175 seconds
IDPM_AUTO_DISABLE is unchecked
SYSOVP is unchecked
Audio Frequency Limit is unchecked
Switching Frequency is set at 800kHz
ACOC is set at Disable
LSFET OCP Threshold is set at 290mV
EN_LEARN is unchecked
IADPT Gain is set at 40X
IDCHG Gain is set at 16X
EN_IDPM is checked
CHRG_INHIBIT is unchecked
Charge Option 1
RSNS_RATIO is set at RAC and RSR 1:1
EN_IBAT is unchecked
EN_PMON is unchecked
PMON Gain is set at 1uA/W
CMP_REF is set at 2.3V
CMP_POL is set at Negative Feedback
CMP_DEG is set at 2 us
FORCE_LATCHOFF is unchecked
FORCE_BATFETOFF is unchecked
EN_SHIP_DCHG is unchecked
EN_AUTOWAKEUP is checked
Charge Option 2
EN_EXTLIM is unchecked
IBAT_SEL is set at Charge Current
Charge Current
Charge Current Limit is set at 0 mA
Maximum Charge Voltage
Charge Voltage Limit is set at 13504 mV
Minimum System Voltage
Minimum System Voltage Limit is set at 9216 mV
Input Current
Input Current Limit is set at 3200 mA
Prochot Option 0
ILIM2_VTH is set at 150%
ICRIT_DEG is set at 100 us
In OCP THRESHOLD is set at 200% of ICRIT
VSYS_VTH is set at 6.00 V
EN_PROCHOT_EXT is unchecked
PROCHOT_WIDTH is set at 12 ms
PROCHOT_CLR is set at Idle
INOM_DEG is set at 1 ms
Prochot Option 1
IDCHG_VTH is set at 16384 mA
IDCHG_DEG is set at 100 us
EN_PROCHOT_CMP is unchecked
EN_PROCHOT_ICRIT is checked
EN_PROCHOT_INOM is unchecked
EN_PROCHOT_IDCHG is unchecked
EN_PROCHOT_VSYS is unchecked
EN_PROCHOT_BATPRESZ is unchecked
EN_PROCHOT_ACOKZ is unchecked
Manufacture ID Read Back
Manufacture ID is set to TI
Device ID Read Back
Device ID is set to <blank>
3.) I tried executing the Procedure Step 3.2 “Charge Regulation and System Load Checks.” But I could not execute step 3.2.1: For SMB Mode: type in “810E” into the 0x12 address and click Write. I am not able to "Write" anything. The "Write Register" button is grayed-out in bqStudio and when I go to "Advanced Comm," I arrive at a window labeled "Advanced Comm I2C. There is an I2C Master Control Panel that has "Write" and "Read" buttons. But, am I not using the SMB version of this EVM (bq24770EVM-540)? How do I use bqStudio to get this EVM to charge my battery line up? Right now V_bat is stuck and around 9V and I_batt is zero. I am able to set a system load and vary the load current, but I can't get anything happening with my batteries.
How do I write to my bq24770EVM-540 with bqStudio? Please let me know.
Thanks,
Carl Olen
Part Number:BQ40Z50
Tool/software: TI-RTOS
Hi,
I am doing a simple query for battery voltage opcode 0x09 ... after having problems with the I2C driver and hardware on my micro (CC2640R2F)
I created a bit banging code (direct IO).. This is to overcome a bug in TI drivers etc...
Anyway All seems OK... I am able to send the query and get back the answer... all seems ok for a few seconds maybe 15-15 transaction at a rate of
300 ms apart.
But than I stop getting any reply.I can see (logic analyzer) that my code is writing the address and opcode... the battery controller responds with ACK on the first
byte (the device addtress) but does not respond with nothing on the second byte (the 0x09 op code). I am NOT getting NACK or ACK on the second byte...
Only after I reset my BLE chip and reload the code I can again see some transport ...
Any ideas are welcomed :-(
BR,
Noam.
Part Number:BQ4050EVM-561
I started bqStudio (version 1.3.54.1, the latest version), selected "Gauge", found both 4500_0_12-bq40z50 and 4500_1_06-bq40z50R1 in the list. But when selected, both gave a warning “The detected device is not compatible with this application! … Proceed at your own risk.”
after proceeding, both selections find bq40z50 and bq40z50R1 at
4500_2_08
Address: 0x17
23.2 degC
Two questions:
1.) What version of the chip is on my bq40z50EVM-561, the bq40z50 or the bq40z50R1?
2.) What do I need to do with bqStudio to be able to read and control my EVM?
Please let me know.
Thanks,
Carl Olen
Part Number:LMZ31710
Do we have an output impedance model for the LMZ31710 module? Customer needs to run PDN power integrity analysis of their power design supplying an FPGA. This design also includes our LMZ31707 and LMZ30602 modules. In the simplest form this would look like a voltage source with series impedance (L+R).
Or maybe there is a way to extract the output impedance from Pspice or webench models?
Part Number:TPS22975
Hi Support,
Currently our products use TI's Load Switch and DC-DC to implement Power's part.
However, there are problems that find that the voltage drop is very large. Therefore, I would like to ask if the IC solution we choose is suitable and whether there are obvious problems with the circuit diagram design.
The attached part is the circuit diagram of this part.
At present, our general situation of Power's Solution is as follows. We find that there is a voltage drop between VCC_3V3_HOST and VIN, and the voltage drop increases as the current rises.
Test data is as follows.
In addition, in the TPS22975 Datasheet, on page 6, it is mentioned that RON at IOUT = -200mA means that if the back load is large, the Load Switch will generate a large voltage drop?
Thanks.
Part Number:TPS22920
We are trying to use TPS22920 load switch (and also tried TP22970 with the same results) to limit inrush current into our SFP+ module. When the module is first plugged in into a powered host board (Switch) it creates multi Amp spike. The EN pin is pulled up to the same input voltage (3.3V) that the load switch is to control. After turn on delay (about 1.5ms) we see the module actually is turning and controlling inrush current to about 300mA, which is expected.
Our capacitive load inside the SFP+ module is 84uF (ceramic caps).
It appears that the power FET transistor turns on uncontrollably during initial plug in for 50us, then turns off, and after the turn-On delay of 1.5ms it turns on second time (as expected while controlling the inrush current).
None of the data sheets scope captures show behavior when VIN transitions from low to high. The only captures shown are for VON to VOUT while VIN is already high.
Is this an expected behavior of these load switches ? Should we be looking at different hot-swappable devices ?
Jerry
Part Number:LM22678
In the above circuit
VIN 4.5V
Rfbb = 1k Ohm
Rfbt = (Vout/1.285-1) * Rfbb
Rfbt = 1.568k Ohm
When applied
VOUT does not output 3.3V.
Please explain.
Thank you.
Part Number:TPS53353
Hi team,
For below TPS53353DQPR schemetic design, my customer has 2 question:
Thanks and looking forward to your feedback.
Max
Part Number:BQ40Z50-R2
To whom it may concern:
In a new design, we use MOLI INR18650M35A cell in 2S1P configuration. The spec is attached. It is a pretty new cell, so no ChemID is available at this point, which is understandable. So we use the online tool to choose a ChemID close to this cell, and the recommends are 2141 and 2144, 3000mAh and 3400mAh. We tried both ChemID, and generate the ROM/SREC file based on the use case, 25W CP discharge.
After the battery fully discharged, the FCC is about 3250mAh, as expected; however, when the battery is charged to 30% and idle for a while, the FCC RemCap and RSOC will all shrink down, as attached. If the battery if fully charged and discharge again, the FCC will increase to 3250mAh range again. Do you have any suggestions to correct this?
We are trying to generate the SREC file with 0.2C discharge now, but afraid after 25W CP discharge, the problem will still exist. Do you think this may be caused by the ChemID?
Thank you!
Chen
Part Number:TPS25221
Is there any long term reliability or functional concerns if EN pin is powered up while IN pin is at 0v?
Hi, our customer want to find an alternative to MP3414A. Do we have p2p device or performance similar device?
Thank you!
Part Number:ULN2003A
Hello experts,
My customer want to get a figure of "Maximum Collector Current vs Duty Cycle" for PW package. (like figure 4&5 in datasheet.) Would you provide it?
Best Regards,
Fujiwara
Part Number:TLC6C5912-Q1
Hello all,
Can you tell me the deglitch time for each fault detection functionality? Also, are these functions available when PWM duty is 100% or 0%?
Thank you,
RYO