Part Number:BQ40Z50
Hi,
For battery with 4 cells on bq40z50r2, how does the fast cell balancing works?
For example, if cell 2 voltage is highest and cell 1 is the lowest, which FET will be opened or closed to balance cell 1 and 2 ?
Thanks
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BQ40Z50: BQ40Z50R2 Cell balancing working algorithm
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BQ27542-G1: Chem ID selction
Part Number:BQ27542-G1
Hi,
I have done battery cycle for 2600 mAh battery and sent logs (Charge, relax, discharge, relax) to GPC (Gauging Parameter Calculator) and received below report.
Best chemical ID : 132 Best chemical ID max. deviation, % : 2.82
In Battery Management Studio, Chemistry Programming, there are 2 entries for 0132 (attached below).
Kindly guide me to select the proper chemistry.
Thanks in advance.
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BQ34Z100-G1: Gas Gauge Sense Resistor Calculation
Part Number:BQ34Z100-G1
Hi All,
I am just about to add the BQ34Z100-G1 Gas Gauge to a new PCB design, but I cannot see on the datasheet how to calculate the sense resistor. The datasheet does quote:
"The value of the current sense resistor should be entered into both CC Gain and CC Delta parameters in the Data Flash Calibration section of the Evaluation Software"
So my next question is, where do I get a copy of the Evaluation Software?
Look Forward to your reply.
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BQ27441EVM-G1B: bqStudio
Part Number:BQ27441EVM-G1B
Hi Tom,
I have the same message that the ' The detected dive is not compatible with this application! '
I have a board BQ27441EVM-G1B connecting to EV2400 version:0.18 Port 12C running bqStudio version: 1.3.54.1.
Do you think I should don't a different version of bqStudio for this board?
thanks,
Anthony
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BQ27510: Specifications typo issue or not
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BQ27520-G4: Reference Design for 2S battery pack
Part Number:BQ27520-G4
I can find two application note for this kind of cases. Basically, we have a external OP for voltage divider.
2011: Multicell Li-Ion and Li-Polymer Battery Gas-Gauge Host Side Application Using bq2750x
2017: bq27426 Gauging Design for Applications With 2 Serial Li-Ion Batteries
For 2011 document, using TLV2241 for this case. But this is a legacy device and I suspect if it 's still working for bq27520.
For 2017 document, using TS321 for this case. This is suitable for lower leakage current 50uA. Since bq27520 apply current is 118uA, I think it's not working for this device.
If so, do we have other reference circuit for bq27520 with 2S battery pack?
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BQ35100: GE / VEN functionality
Part Number:BQ35100
Hi folks -
I'm looking at the BQ35100 for a 2-series cell application. I'm following the EVM schematic and user guide. It seems to me that there are not any extra operations required to toggle the VEN pin. Is that correct?
I'm assuming that any logic required to toggle VEN happens automatically with GE.
Thanks!
Jake
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BQ78350: BQ78350-R1=BQ76940 Integration of charging and discharging application
Part Number:BQ78350
Hi,
The current design for BMS output is using charging and discharging integration structure.
After the end of charging process, the charge MOSFET function of BQ78350 will be disabled. When the circuit dischaging, the current will flow through the body diode of charge MOSFET first. After the discharging current can be detected, the charge MOSFET will open again.
The bench test result shows it takes about 357ms from the discharging current detected to Charge MOSFET open. That is say, the current all flows through MOSFET's body diode during this 357ms.
Question: Is there a method to make the time shorter?
Regards,
Lenna
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BQ78350: BQ78350: the selection for auto ship and sleep
Part Number:BQ78350
Hi,
The corresponding battery model can be selected in Chemistry. However, due to the consideration of life problem, the voltage range is reduced from 2V-4.25V to 3-4V. And then the RSOC is not correct, but after learning, the result become more accurate. Considering long -distance transportation, select ship function(small self-consumption). While ship mode means shutdown, when restart RSOC will reduce from 100% to 75%.
Question: which mode should be selected?
Best regards,
Lenna
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BQ27500: BQ27500 EVM recognized as BQ27500 in BQstudio
Part Number:BQ27500
My customer is having issues with BQStudio registering the dual BQ25700A EVM as the BQ25700 when connected.
It responds when connected, but there is no profile for the BQ25700 so he is having issues getting to some of the registers he needs for proper testing.
Is there already a profile or a plan to make a profile for the BQ25700 in BQStudio?
This may be due to the EVM they have being built personally for them.
Regards,
Joe
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BQ34110EVM-796: Role of J3 in BQ34110 EVM
Part Number:BQ34110EVM-796
I'm trying to understand every detail of BQ34110 design based on the BQ34110 EVM. I still don't understand what J3 is used for. In the BQ34110 EVM user's guide (SLUUBI1), section 3.2.1 said that J3 is used to select the mode of operation, but doesn't explain any further. So I wonder which mode is it about?
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BQ78350-R2-DEVICE-FW: Understanding IPScale
Part Number:BQ78350-R2-DEVICE-FW
Hello,
We have just designed a new BMS for a 7S pack for a special power tool, using bq78350-R2.
We need to set some protections like OCD Threshold and SOCD Threshold around -40A and -50A, but these values exceed the max allowed programmable value of -32768mA.
I understand the role of the IPScale parameter, but it is unclear the usage:
If I set IPSCALE = 0x01 (bit15-12= 0001), I understand that some readings are scaled by a factor of 10^1, but I don't understand which settings need to be saved in the DataFlash scaled by 10, and which not:
- do ALL the current settings expressed in mA need to be scaled ?
- do ALL the capacity settings expressed in mAh need to be scaled ?
If only a part of the parameters need to be scaled, which one are affected by the IPSCALE ? and which not ?
Thanks in advance.
Pietro
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BQ40Z50-R1: CHG/DSG FETs never come on, FUSE stuck high.
Part Number:BQ40Z50-R1
Working on a new design for a battery pack using bq40z50-r1 and having issues with bringing it up. The device does wake up, but no matter what I do I can't get a load to pull power from the battery nor can I charge it.
I have a .log where I change the FUSE_EN bit in data memory, but as you can see the CHG and DSG bits in the Operation Status A reg never come on.
Attached are the log and the .gg files.
Thanks for any help!
Mike
(Please visit the site to view this file)
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BQ27741-G1: Battery Charger and Fuel Gauge
Part Number:BQ27741-G1
Hi--
I'm new to battery fuel gauging and have been experimenting with Sparkfun's Battery Babysitter:
which is a combo of your BQ24075 battery charger and a BQ27441-G1A fuel gauge.
I am powering the battery charger with a 6V, 3W solar panel.
I am trying to use a 4400mAh LiPo battery that is two cells wired in parallel:
cdn-shop.adafruit.com/.../C449_-_ICR18650_4400mAh_3.7V_with_PCM_20140728_APPROVED_8.18.pdf
I've been reading
cdn.sparkfun.com/.../BQ27441-G1-users.pdf
I know the gauge should be good up to 8000mAh, but is it ok to use with two cells in parallel? The literature states one cell. Is this application ok?
Please feel free to point me to documentation and/or other devices that might help.
--BB
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BQ8055DBTR
Anybody know the BQ8055DBTR IC information or Old Parts as bq2060 ?
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BQ78350-R1: A list of Data Flash values that require a reset
Part Number:BQ78350-R1
Hi,
I want to update some data flash values in the bq78350 R1.
Some of the gas gauges are in batteries that already had learning cycles and I prefer not to reset the gas gauge to keep MAX_ERROR low.
Do you have a list of DF values that require a reset?
these are the DF (addresses and description) I need to change:
0x4280 - Qmax LearnedFullCharge
0x4525 - Fixed EDV 012 hold
0x4538 - FCCLearnUpDown
0x4556 - Design Capacity mAh
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BQ27542-G1: Want to know the capacity of ChemID suggested (SDI - 0132)
Part Number:BQ27542-G1
HI,
I have uploaded 2600 mAh battery logs (charge_relax_discharge_relax) to GPC for Chem ID.
I received report suggesting 132 with deviation % = 2.7
Below entry i found in Chemistry Programming list of Battery Management Studio.
SDI - ICP103450S - 0132 - LiCoO2/carbon 6, -20C, OCV refined
Can someone please let me know what is the Capacity of above entry?
Thanks.
Basavaraju
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BQ34Z100-G1: CE pin
Part Number:BQ34Z100-G1
Dear All:
do you think the CE pin can be floating? why i measure the CE pin voltage is 0.8V at floating condition？ Thanks~
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BQ34110: conflict between bqstudio CC Offset displayed format and TRM
Part Number:BQ34110
The TRM says that CC Offset is an I2 ranging from –32767 to 32767.
But on the data memory tab under calibration, bqstudio displays a floating point number (for example -42.96).
Which one is right?
Also, the TRM says that the default value is -1432. How does one convert from -1432 to -42.96? The floating point conversion in TRM says it is for CC Gain and CC Delta.
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BQ40Z60: Overload protections triggering even when disabled
Part Number:BQ40Z60
We have designed a custom implementation of the BQ40Z60, closely based off of the EVM design. The major changes were: using pairs of parallel FETs (BSC090INS) instead of the single charge and discharge FETs, to allow for higher peak discharge currents. We also changed the output inductor and capacitors to allow for a charge rate of 4.5A. Our battery is a 4S4P LiIon pack, with a total capacity of 200Wh.
We have encountered a rather puzzling issue when attempting to discharge the packs at a relatively high (28A) current.
Here are the symptoms and diagnostic steps so far:
1: With all protections disabled (Enabled Protections A through D all set to 0), attaching a load that draws 28A causes the CHG and DSG FETs to stay on for only 30ms before shutting off for one second before turning on for another 30ms. The BMS keeps switching the FETs on and off this way, with 30ms pulses at exactly 1 Hz. In BQStudio and in the logs, the CHG and DSG enable bits on Operation Status A can be observed to turn off. But none of the protection or safety status bits are activated during this. The other strange thing that happens is the discharge currents in the cells are very imbalanced when this is happening, one cell appears to have very high current as indicated in BQstudio, while the other cells have almost no current. See “discharge_test_RSNS0.log”
2: After some trial and error, we found that we can get the cycling of the FETs to stop, and for the pack to discharge normally with the 28A load, by simply changing the RSNS bit from 0 to 1. (See “discharge_test_RSNS1.log”) According to the TRM, the RSNS bit doubles the sense resistor voltage thresholds that trigger the AOLD, ASCC, ASCD1 and ASCD2 overload and short circuit protections. I can understand how a high current could trigger van overload, and how doubling the voltage threshold could cause the triggering to stop. But I don’t understand why a protection that is disabled, and that has not been recorded or indicated as having triggered, would be activating at all. Shouldn’t disabling all protections mean that discharge should not be limited by the BMS at all? We do not actually plan to disable all the protections in practice, but we simply want to verify that we have control over them, and that none ever trigger in an undesired and unexpected manner.
What do you think is causing this behavior?
(Please visit the site to view this file)(Please visit the site to view this file)
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