SLUAAQ0 March   2025 BQ27Z558 , BQ27Z561 , BQ27Z561-R1 , BQ27Z561-R2 , BQ27Z746 , BQ27Z758 , BQ28Z610 , BQ28Z610-R1 , BQ34Z100-G1 , BQ34Z100-R2 , BQ4050 , BQ40Z50 , BQ40Z50-R1 , BQ40Z50-R2 , BQ40Z80 , BQ41Z50 , BQ41Z90

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Generating a Key File with BQKEYPACKAGER
    1. 1.1 SHA1 Process
      1. 1.1.1 How to Calculate SHA1 Key
    2. 1.2 SHA256 Process
    3. 1.3 ECC Process
  5. 2Programming a Key Into the Fuel Gauge With BQKEYPROGRAMMER
  6. 3Programming Keys in Production
  7. 4Summary
  8. 5References

Abstract

Most Texas Instruments battery fuel gauge products support authentication for anti-counterfeit protection of battery packs. This application note describes the process of creating a SHA or ECC key using BQKEYPACKAGER, programming the selected key onto a gauge using BQKEYPROGRAMMER, as well as guidance on programming the key in a production environment.

The purpose of these two tools being standalone is to allow an OEM to encrypt authentication keys in a file and send to a packmaker. The packmaker can then use this file as the data source for BQKEYPROGRAMMER to program the key onto a gauge. This way the key is not visible to the packmaker.