Dear TI Experts,
We were convinced to use the BQ40z80 as BMS in our system, due to its manifold of functions and its compact size. There are three engineers working on this task. After twelve weeks of development all of us are convinced that the documentation of the BQ40z80 needs to be reworked massively. It is simply not economical to work with the BQ40z80 if you have to hire someone for several weeks who digs through the documentation trying to understand the functionality the way it is written. Even though we have already invested twelve weeks of work and a lot of money for prototype PCB manufacturing, we are considering to switch to another IC before we reach a point of no return. You could save thousands of hours of work for lots of engineers out there, by offering some more information and better structure in your documentation. Usually, Texas Instruments is a source of high quality, concise and clearly structured manuals, we really like to work with. This is also the reason, why almost 70% of the ICs we are using, are manufactured by Texas Instruments. The technical reference manual for the BQ40z80 is none of the above.
Things we find worth to change with high priority:
a) In the technical reference manual we were not able to find out the data types of the individual values of commands returning "mixed" data.
b) In the technical reference manual almost no functional description in text form is available, the whole documentation consists of "state machines" written in tables. This feels like reverse engineering assembler code, not like reading a programming manual. While trying to understand the functional description of the chip functionalities, one is constantly looking up abbreviations of register names. When the register is found, the only description consists of a name in clear text. In one case, the only description was "reserved, do not use". In the end one can never be sure what the chip is actually doing, which is a massive deal breaker for a safety relevant component like the power supply.
c) We are right now using the schematic that is found in the datasheet that you offer to show our job students how a schematic should definitely not look like. Maybe you might want to clean this up before you officially release the chip. Nicer version of the schematic is attached as example of how it could look like.
Will you please be so kind as to informing us whether or not we can hope for a new, massively improved documentation in the next few month?
Thanks,
Jan
