BQ4050 Datasheet, PDF (36/53 Pages) Texas Instruments – CEDV Gas Gauge and Protection Solution

bq4050
SLUSC67A – MARCH 2016 – REVISED MARCH 2016
www.ti.com
Figure 30. ESD Protection for SMB Communication
8.2.2.2.5 FUSE Circuitry
The FUSE pin of the bq4050 is designed to ignite the chemical fuse if one of the various safety criteria is
violated. The FUSE pin also monitors the state of the secondary-voltage protection IC. Q5 ignites the chemical
fuse when its gate is high. The 7-V output of the bq294700 is divided by R16 and R6, which provides adequate
gate drive for Q5 while guarding against excessive back current into the bq294700 if the FUSE signal is high.
Using C3 is generally a good practice, especially for RFI immunity. C3 may be removed, if desired, because the
chemical fuse is a comparatively slow device and is not affected by any sub-microsecond glitches that come from
the FUSE output during the cell connection process.
36
Submit Documentation Feedback
Figure 31. FUSE Circuit
Product Folder Links: bq4050
Copyright © 2016, Texas Instruments Incorporated