AFE Communication Permanent Fail
41
SLUUBD3D – September 2015 – Revised September 2018
Copyright © 2015–2018, Texas Instruments Incorporated
Permanent Fail
4.15 AFE Communication Permanent Fail
The device monitors the internal communication to the AFE hardware and increments the AFE read/write
fail counter on any communication error. If the read or write fails exceed a limit within a configurable
timeframe, the device disables the pack permanently.
Status
Condition
Action
Normal
AFE read/write fail counter = 0
PFAlert()[AFEC]
= 0
Alert
AFE read/write fail counter > 0
PFAlert()[AFEC]
= 1
Decrement AFE read/write fail counter by one
after each
AFEC:Delay Period
Trip
Read and Write Fail counter
≥
AFEC:Threshold
PFAlert()[AFEC]
= 0
PFStatus()[AFEC]
= 1
Class
Subclass
Name
Type
Min
Max
Default
Unit
Permanent Fail
AFEC
Threshold
U1
0
255
100
counts
Permanent Fail
AFEC
Delay Period
U1
0
255
5
s
4.16 AFE XREADY Permanent Fail
The companion bq769x0 AFE includes an internal self-check, and if this check fails, then the XREADY bit
is set. Each time the bq78350-R1 reads the AFE it checks this bit, and if it is set, then increments an
internal counter. If this counter reaches a configurable limit, then the device disables the pack
permanently.
Status
Condition
Action
Normal
XREADY counter = 0
PFAlert()[AFE_XRDY]
= 0
Alert
XREADY counter > 0
PFAlert()[AFE_XRDY]
= 1
Decrement AFE_XRDY counter by one after each
AFE
XREADY:Delay
period
Trip
XREADY counter
≥
XREADY: Threshold
PFAlert()[AFE_XRDY]
= 0
PFStatus()[AFE_XRDY]
= 1
Class
Subclass
Name
Type
Min
Max
Default
Unit
Permanent Fail
AFE XREADY
Threshold
U1
0
255
100
counts
Permanent Fail
AFE XREADY
Delay Period
U1
0
255
5
s
4.17 Instruction Flash (IF) Checksum Permanent Fail
The device can permanently disable the battery if it detects a difference between the stored IF checksum
and the calculated IF checksum only following a device reset.
Status
Condition
Action
Normal
Stored and calculated IF checksum match
—
Trip
Stored and calculated IF checksum after reset does not match.
PFStatus()[IFC]
= 1
BatteryStatus()[TCA]
= 1
BatteryStatus()[TDA]
= 1
4.18 Data Flash (DF) Permanent Fail
The device can permanently disable the battery in case a data flash write fails.
NOTE:
A DF write failure causes the gauge to disable further DF writes.