Quantcast
Channel: Power management forum - Recent Threads
Viewing all 35901 articles
Browse latest View live
↧

BQ40Z80: bq40z80 for LTO batteries

June 29, 2018, 5:06 am
$
0
0

Part Number:BQ40Z80

We have to make a BMS for 5 series cells of LTO chemistry. Can we do below settings in bq40z80 :

1. Lower cut off required is: 1.8V/cell

2. Upper Cut off: 2.96V/cell

3. Continuous load: 25Amps 

4. Peak Load: 60Amps for 10msec

5. Continuous charge: 30Amps

6. balancing current: 1Amps  to be set by external mosfets

7. Battery capacity: 100Ah  (Can set value of resistor divider to 1/3, to accomdate this value in software)

Dear Aki,
 
We have to make a BMS for 5 series cells of LTO chemistry.
1. Lower cut off required is: 1.8V/cell
2. Upper Cut off: 2.96V/cell
3. Continuous load: 25Amps
4. Peak Load: 60Amps for 10msec
5. Continuous charge: 30Amps
6. balancing current: 1Amps
 
Do you have solution for this.
 
 
Thanks
Deepak Bansal
Pinaka Battery Solutions
+91-9215611008

↧
Search

BQ27320: How to configure fuel gauge when not depleting battery completely?

June 29, 2018, 6:07 am
$
0
0

Part Number:BQ27320

In my application I can discharge the battery from 4.2v to appx. 3.1v, at that point one components stops working and the system will shut down. The batteries I use can discharge down to 2.5v. When acquiring the test data for GPC, should I discharge the batteries down to 2.5volts (since this is the "battery soc" = 0%)? Or should I discharge only to 3.1v as this is the "application soc" = 0%. In either case I suppose I set the CellTermV=3100 in the config.txt file.

For now I have discharged the batteries to 3.0v in the test set. When testing the fuel gauge the soc estimate jump from 23% to 7% during discharge. I thought this might be due to overestimation of the Design Capacity, so I set both Design Capacity and Learned Full Charge Capacity to the actual mAh obtained during discharge to 3.1v, instead of the factory rating which is based on discharge to 2.5v. The soc jump was smaller this time, from 11% to 7%, and again I thought the capacity was overestimated. To my surprise, however, the Learned Full Charge Capacity had increased increased slightly instead. What can be the cause of this jump? I am using compensated EDV voltages, could that have anything to do with it? Would it be better to use fixed EDV voltages?

My question is really what is the recommended way to set up the fuel gauge in this case where the battery 0% level is not the same as the application 0% level.

↧
↧

BQ34110: Cycle count does not increment after qualified discharge

June 29, 2018, 7:05 am
$
0
0

Part Number:BQ34110

Hi - I am not able to get the Cyclecount() report to increment after spending a week in configuration tweaking & charge/discharge cycles.

I know you'll need data, so what data will I need to provide in order for you to help me assess this? (image srec, charge/discharge logs, etc)

thanks, -pete u.

↧

BQ33100: CHGLVL0 and CHGLVL1 floating

June 29, 2018, 10:21 am
$
0
0

Part Number:BQ33100

I will be using a BQ33100 alone without a BQ24640 as I'm limiting supercapacitor current in-rush with a large panel resistor. Since I won't be using CHGLVL0 and CHGLVL1 should I leave those pins floating and connect to ground? 

↧

BQ34110: Device not detected from bqstudio after first try

June 29, 2018, 12:37 pm
$
0
0

Part Number:BQ34110

Using a bq34110 to measure various values against a known power supply for testing, and connecting it to a pc with bqstudio via an ev2400 adapter, everything runs smoothly at first. However, upon closing the application and running it a second time, I run into the issue of the bqstudio saying that no device is detected (literal: "Auto Detected Device: None"). All I have tried during the first run was to perform some I2C communications via the "advance communications" section of bqstudio (which were successful, for the record). I tried to search on the forum for a similar issue, but no such records could be found. All I have seen so far has related to updating the firmware of the ev2400 (which is already up-to-date), and having the latest version of bqstudio.

↧
↧

BQSTUDIO: Help regarding programming BQ4050 with BQStudio

June 30, 2018, 1:29 am
$
0
0

Part Number:BQSTUDIO

Hi,

This is my setup: 4 Li-ion cells in series. BQ4050 with CEDV algorithm is used for cell balancing.

My concern is:

I want to charge all 4 batteries only up to 3.75V instead of its peak voltage of 4.2V. It implies the max voltage of all the cells in series is 15V. I do not know which parameters to change in BQStudio to accommodate these specifications. I have already set all the voltage thresholds according to my requirements. But I am concerned when will BQ4050 will start cell balancing. 

1. Do I need to change any parameters in BQStudio Data Memory for correct working? I am reading the technical reference of BQ4050 and have already gone through the Advanced Charging Algorithm Section. But I am not able to completely understand everything and I am concerned what changes will I have to make.

2. Since my max voltage for each cell is only 3.75V. How do I perform my GPC cycle? The GPC cycle asks to charge the batteries to 100% and then discharge it. But in my case, the cells will reach a max voltage of only 3.75V. But the actual capacity of cells is more. So, what would be the steps for GPC cycle? - a). Start discharging at 3.75V or b). Start discharging at 4.2V.

  

↧

BQ34Z100-G1: Charge Hys V Shift

June 30, 2018, 7:50 am
$
0
0

Part Number:BQ34Z100-G1

Hi,

In a previous discussion referring to the Charge_Hys_V_Shift parameter, you said:

----------------------

"Parameter: Gas Gauging>IT Cfg> Charge Hys V Shift

It helps the gauge to avoid Qmax update in the flat region after a charge. The gauge takes the OCV during relaxation after charge.

The Voltage drops during charging relaxation.

If the OCV < Flat region upper bound + Charge Hys V Shift, then Qmax update is not allowed to avoid an inaccurate Qmax update occurred by incorrect OCV information."

----------------------

I understand the concept but what determines the "Flat region upper bound" ?

↧

BQ34Z100-G1: bq34z100 JEITA compliance and Management Data: ChargeCurrent?

June 30, 2018, 8:07 am
$
0
0

Part Number:BQ34Z100-G1

Hello again,

Three questions relative to the Charge Current value:

In the Bq34z100-g1 spec , aka SLUSB75B Revised July 2016

It shows the units of measure for the Charge Current T1-T2  (and T2-T3, T3-T4) in percent.

1) Shouldn't that be mA instead of percent?

2) Is this the identical value that  "ChargeCurrent()" returns? I would expect mA, or does it just return whatever value I assign?

3) Is this value used in any way in the impedance tracking algorithm or it just for user/programmer reference?

-Tim

↧
Search

BQ78350-R1: OCD (Over Current Discharge) Safety Alert

June 30, 2018, 11:02 am
$
0
0

Part Number:BQ78350-R1

Hello, I am using BQ78350-R1 with BQ76940. Everything was Ok. But now, OCD safety alert is detected and OCD flag is activated without any discaherge current. And then this flag can not be cleared with charging, reset and clear permanent failuer commands. 

Please urgent help. Thanks in advance.

Yusuf KAYA

↧
↧

BQ34110: bq device accumulated values lost when data flash reprogrammed?

July 1, 2018, 5:47 am
$
0
0

Part Number:BQ34110

We re-program the data flash at power on (if the DF version we expect does not match).

We've noticed that the cycle count field in data flash is reset when we do this.

We wonder if there are any other values (internal registers) that are reset/erased/overwritten in the bq device when we re-program data flash that can have an adverse effect upon bq operation (such as accumulated charge, accumulated charge time, last accumulated charge, last accumulated time, SOH/state of health, DCR/discharge count register, etc).

We need to know in case we update our product's firmware in the field (and the new firmware contains a new data flash image that causes us to erase/reprogram the data flash) and doing so causes loss of bq operating information that has accumulated with product operation before the update.

↧

BQ40Z60: Register not referenced in the Technical Reference Manual

July 1, 2018, 10:50 pm
$
0
0

Part Number:BQ40Z60

HI, Onyx: I encountered the same problem above and I often try to find the answer in the BQ40Z50 file, but I still can't explain it. TI should update the Technical Reference Manual corresponding to the current F/W version.

Can we get new documents?

Janson

↧

BQ27742-G1: Firmware upgrade using (.bq.fs) file

July 2, 2018, 12:34 am
$
0
0

Part Number:BQ27742-G1

I have stored the (.bq.fs) file in my flash. I am able to read the desired commands addresses and data. The commands with 0xAA device address are being transmitted succesfully.

But when i encounter the first command with (0x16) Device address , I am not getting any acknowledge from the device.  I am not sure what address does 0x16 correspond to. Also is it a 7-bit address or a left shifted 8-bit address? Here are the command until which it executes successfully.

;--------------------------------------------------------
;Unseal device
;--------------------------------------------------------
W: AA 00 14 04
W: AA 00 72 36
W: AA 00 FF FF
W: AA 00 FF FF
X: 1000
;--------------------------------------------------------
;Go To ROM Mode
;--------------------------------------------------------
W: AA 00 00 0F
X: 1000
W: 16 00 04 00 00 00 83 DE    // The command which fails to recieve acknowledge from the device.

Could anyone help?

Thank you

↧

USB2GPIO-LOADER-SW: Cannot find Firmware

July 2, 2018, 1:04 am
$
0
0

Part Number:USB2GPIO-LOADER-SW

I got the loader SW installed, but cannot find a newer firmware anywhere.

Can someone post a link here please?

I have 1.0.10 and need at least 2.0.19 according to BQ77908 configuration tool.

Thanks!

↧
↧

BQ40320 programming specifications

July 2, 2018, 4:00 am
$
0
0

Hello,

I would like to ask you about BQ40320. From Chinese customer we received request to implement programming support for this chip.

It seems that this is custom chip and documentation is not publicly available. Is it possible to provide us device datasheet and prog. spec. of this chip?

Best regards,

Frantisek

↧

BQ28Z610: Batteries is inserted wrong orientation

July 2, 2018, 4:33 am
$
0
0

Part Number:BQ28Z610

Hi TI.

I designed product that use 2 batteries config 2s1p. My batteries are Panasonic 18650 3400mAh.

Could you tell me what happen when I insert wrong batteries orientation in case 2, case 3 and case 4 (see my attached picture). 

Thanks.

Tam.

↧
Search

BQ78350-R1: Device DF was broken after device shutdown

July 2, 2018, 4:46 am
$
0
0

Part Number:BQ78350-R1

Dear all,

I'm working at production of 6s-4p Lithium ion battery pack with BQ78350-R1 and BQ76930.

When we're producing battery pack at our mass production line, some of devices showed SMBus communication error.

Our production process are followings.

1. to write our DFI file to target PCM and conduct function tests

2. to assemble PCM and battery cell (core pack assy.)

3. to conduct core pack function tests

4. after core pack tests, to send shutdown command via SMBus.

5. then, to assemble final pack and conduct final inspection.

6. at the procedure 5, we found SMBus communication error.

Error information and our investigation results are followings.

1. SMBus communication error means RSOC shows 771% and other command codes can't recieve.

　※see attached image1

2. The failure IC can overwrite FW by BQSTUDIO.

3. After overwrite FW and our DFI, we send shutdown command, but same failure was found.

4. to import srec from failure IC and compare with srec which is before break, 256 byte data seems to be changed to erased state(0xFF).

　　※see attached image2, left:failure right:normal 

5. These failure were found at only specific IC lot 6AK-AC02. We found this failure total 20 of 480pcs. All failure are same phenomenon.


How can I solve it?

image1: registers value

image2: srec_diff    left: failure  right: normal

↧

BQ20Z95: FCC should only be a Portion of the maximum possible Chemical Capacity

July 2, 2018, 5:51 am
$
0
0

Part Number:BQ20Z95

Hi,

We currently are working on a "old" product that we have to maintain and support.
The current cells are not available anymore so our customer selected a new cell for us to assemble the pack. 
Since it is a new Cell I started with the cycles for the ChemID and got stuck at reconfiguring the bq20z95.

My Problem is that the old cell had way less capacity in comparison to the new one. Our Customer does not want a significant increase in capacity for reasons unknown to us and he will most likely not drop this Requirement.

The whole Gas Gauging Algorithm used by bq20z95 depends on the Chemical depth of discharge and the total chemical capacity Qmax. Therefore, as I understand we have to set the chemical Qmax for the new Cell with a Golden Cycle that will Result in the real chemical capacity the Cell has so that the ChemID and OCV-Tables as well as the Gauging in its entirety will still work.

Further i think we can increase the DF:Terminate Voltage and DF:Reserve Capacity to Reflect the FCC we actually want. As an Example
with a 3000mAh Standard Cell with 30% at 3.6V we would have a FCC of 2100 as long as we set the DF:TerminationVoltage to 3.6V
and the DF:ReserveCapacity to 900mAh. This way we could still use the "usual determined" ChemID and the OCV-Tables would also not 
disrupt anything as long as we stay above the 3.6V. Is this Assumption correct?

I was reading the "SLUA364 - Theory and Implementation of Impedance Track". It is not clear for me if the DOD1 and DOD2 used at 
the new "TerminationVoltage" would Result in a Qmax of 2100 when the previous settings in the example are used and if there would
be any weird behavior in the GasGauging itself.

Can u tell me if the simple parameterchange proposed and a Golden Cycle with these Settings as well as the ChemID i got from Cycling the 
Cell (min/max values specified in the Datsheet) would give us the Outcome our Customer wants or if we have to approach this from a different angle ?

Thanks in advance

    Robert Andris

↧
↧

BQ78350-R1: Short circuit protection fails

July 2, 2018, 7:41 am
$
0
0

Part Number:BQ78350-R1

Hi,

I have a problem with proper short circuit protection design  for BQ78350-R1 working with BQ769200 AFE IC. Battery is protected using OptiFets two parallel  for charge and two parallel for discharge. Transistors are rated for 100A.

A short circuit in discharge protection is configured as listed below.Both Latch and normal protection is enabled in settings. And was tested to work as configured, close FET if there is a short circuit, open and close after 10s and then latch for 240s. During short test in office we do not observed temperature rise.

During 1h short circuit test in 50 degC conducted by certified body after 15minutes protection failed and battery burned.

So my questions is what are possible purpose of short circuit protection fail as designed in BQ76920?

Second: what can be the purpose of over temperature protection fail than?

Third: is there any way to configure or design more reliable protection against long lasting short circuit for example prevent recovery if the latch limit is exceded? Using BQ769200 and BQQ78350-R1 of course.

Any help would be appreciated.

↧

BQ35100: Panasonic CR2450 Li/MnO2 Coin Cell

July 2, 2018, 3:47 pm
$
0
0

Part Number:BQ35100

In the Texas Instruments document SLUA904 it states, "If you cannot find your specific model contact Texas Instruments on model generation."  I plan to use the bq35100 in SOH mode using a Panasonic CR2450 Li/MnO2 Coin Cell.  What Chem ID should be used for this application?  Thanks!

↧

BQ34Z100-G1: BQ34Z100-G1 Learning Cycle Finaly Operation

July 3, 2018, 12:41 am
$
0
0

Part Number:BQ34Z100-G1

Hi everyone;

With the BQ34Z100-G1, the tests go well. Those made;

1) IT_enable is active. Then VOK and QEN is set. It was charged with C/3 full charge with an empty and relax battery. Then wait 2 hours. As result UPDATE_STATUS is 1, Omax Cell 0 update and Max Error is %3. 

2) I started to discharge at C/5.. VOK is set.  I waited 5 hours after the battery was completely drained. Then Ra Table updated. Qmax Cell 0 updated. Max Error %1 Leraned Status 2. 

What should I do after this? When can I get a Golden Image file?

I have worked with this document. 

http://www.ti.com/lit/an/slua597/slua597.pdf 

Sincerely,
Faruk Sözüer

↧
Viewing all 35901 articles
Browse latest View live
Search
<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>