Odd behavior discharge FET in design with bq20z45
Hello,We have a battery pack design around the bq20z45. The same PCB is used with multiple cell types and configurations. Works perfectly on the bench with lab supplies and loads. Our customer...
View ArticleCan't change SHA-1 authentication key
I am using BQ34Z100 with a MCU controlling it. But I can't change the SHA-1 authentication key via I2C. Here are the steps. First I write 0x00 to 0x61 to enable the authentication data commands. Next I...
View Articlebq40z60 - Current measured is over 65% too high
Hi,I have a board with a bq40z60 circuit copied from the evaluation module. When I look at the discharge current value on bqStudio, I see values that are consistently about 65% higher than what I...
View ArticleWriting to data flash with BQ27531
I am trying to write to Data Flash as described in section 5.5.1, Modify WRTEMP of OpConfigB Register, of SLUUA96. The Data Flash does not change after I follow the given procedure.I am communicating...
View ArticleBQ40z50 opens charge FET on charge termination even though CHGIN bit is zero.
I'm working with the BQ40z50 guage, and I want the charge FETS to remain on even when the pack is at 100% charge. According to the technical reference manual, setting CHGIN in Fet Options to zero will...
View ArticleBQ40Z60 Gauging Issue
I am using the BQ40Z60EVM to charge 2 series Li-ion NCR18650B. I have completed the learning cycle; max error updated to 1%, update status changed to 6, and qmax updated. Even still the gauging is not...
View Articlebq27530 learning cycle qen always set to 1
HiI am using bq27530-g1 and trying to finish the learning cycle.in the last discharge the battery get to 0% as it should after few hours the VOK is set to 0 as it should. the "update_status_0" is set...
View ArticleBQ40z50 SREC Programming
I'm writing a program for our battery production which, among other things, will load an SREC file into a BQ40z50 device.I have logged the transactions from BQStudio when programming an SREC but there...
View Articlebq34z100-G1 : no chemestry id
I want to start develop a Gas Gauge with the bq34z100-G1there is no chemestry id for the lead acid batteries1. Fiamm FG21202 : 12V 12 A/h2. Fiamm 12FGH23: 12V 5Ah3. Fiamm FG21803: 12V 18AhIf there is...
View ArticleBQ27441 Default values not matching datasheet
I'm trying to use the BQ27441 gauge. All commands (Voltage(), Temperature()...) seem to work. I can write to data memory and read back the values and the fuel gauge also seems to react correctly to the...
View ArticleBQ20Z45-R1 CUV Not turning back ON properly
I am using the BQ20Z45-R1 with a Li-Ion pack setup as a 4S3P. I currently have the CUV threshold set to 2500mV and recovery set to 3375mV. I am experiencing the following:-CUV threshold is reached at...
View Articlebq40z60 Power Ground (PGND) and Analog Ground (GND)
The document SLUSAW3C section 12.1.1 #8 tells us we should connect power ground to device ground (analog ground) with a zero-ohm resistor or thermal pad at one point. However, for the bq40z60EVM board...
View ArticleBQ34Z100 Register question
Customer has this question:I have another question on the BQ34Z100-G1 part. I am writing a test application to read the current sense value from the part in order to verify my charging circuitry....
View Articlebq40z60 wake command with no charger present
Everything I can find for this question seems to require we apply power to VAC first. I desire for the circuit to be automatically powered from the moment the battery itself is connected, even if the...
View ArticleAny date for BQ78350 FW update?
I have been told in another post that a firmware update for BQ78350 is planned in August.I'd like to know if everything is on track. That update is critical for us.Regards,Frederic
View Articlebq40z50 Current Offset Error
Hello,I have a design using bq40z50 and a 1mOhm sense resistor. After current calibration, I notice a large current offset of about -20mA in both charge and discharge direction. However, at rest, there...
View ArticleState of health (SOH) calculation for BQ27411-G1
We've been working on the design of a brand new flow transmitter that uses energy harvesting to charge a Li ion battery, there is a bq27411-G1 for battery gauging purposes, the question is: How is the...
View ArticleEV2400 recognized as unknown device
Hi,I just bought a EV2400 and when I plug it into any USB available in my computer (W7-64 bit), the device is not recognized.It's shown as unknown device in device manager with the following status:...
View ArticleBoard offset calibration with bq20z95
Hello,I am trying to make a board offset calibration. I use your datasheet SLUA379B–May 2006–Revised January 2010.'// WRITE BOARD OFFSET TO DATA FLASH. FROM DATA MANUAL, SUBCLASS=104, OFSET=161Error =...
View ArticleBQ3060- SMBus pull up resistors, I2C interface compatibility
Hello everyone.I wanted to know what value of pull up resistors should I use for SMBus? I am planning to use BQ3060 as slave and ATSAMA5D36(...
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