2.1 Introduction
This chapter describes the gauge's recoverable protection. When the protection is triggered, charging and/or
discharging is disabled. This is indicated by
OperationStatus()[XDSG]
= 1 when discharging is disabled (DSG
FET is turned OFF), and
OperationStatus()[XCHG]
= 1 when charging is disabled (the CHG and PCHG FETs are
turned OFF). Once the protection is recovered, charging and discharging resumes. All protection items can be
enabled or disabled under
Settings:Enable Protections A
and
Settings:Enable Protections B
.
To protect the DSG FET body diode, the DSG FET will always be closed when
Current()
>
Charge Detect
Current
, including when
OperationStatus()[XDSG]
= 1. Likewise, to protect the CHG FET body diode, the CHG
FET will always be closed when
Current()
≤
Discharge Detect Current
, including when
OperationStatus()[XCHG]
= 1.
2.2 Cell Undervoltage Protection
The device can detect undervoltage in batteries and protect cells from damage by preventing further discharge.
Status
Condition
Action
Normal
Min cell voltages 1..2 >
CUV:Threshold
SafetyAlert()[CUV]
= 0
BatteryStatus()[TDA]
= 0
Alert
Min cell voltages 1..2 ≤
CUV:Threshold
SafetyAlert()[CUV]
= 1
BatteryStatus()[TDA]
= 1
Trip
Min cell voltages 1..2 ≤
CUV:Threshold
for
CUV:Delay
duration
SafetyAlert()[CUV]
= 0
SafetyStatus()[CUV]
= 1
BatteryStatus()[FD]
= 1,
[TDA]
=0
OperationStatus()[XDSG]
= 1
Recovery
Condition 1:
SafetyStatus()[CUV]
= 1 AND
Min cell voltages 1..2 ≥
CUV:Recovery
AND
Protection Configuration[CUV_RECOV_CHG]
= 0
Condition 2:
SafetyStatus()[CUV]
= 1 AND
Min cell voltages 1..2 ≥
CUV:Recovery
AND
Protection Configuration[CUV_RECOV_CHG]
= 1 AND
[CUV_RECOV_CHG]
= 1 AND
Charging detected (that is,
BatteryStatus[DSG]
= 0)
SafetyStatus()[CUV]
= 0
BatteryStatus()[FD]
= 0,
[TDA]
= 0
OperationStatus()[XDSG]
= 1
2.3 Cell Overvoltage Protection
The device can detect cell overvoltage in batteries and protect cells from damage by preventing further charging.
Note
The protection detection threshold may be influenced by the temperature settings of the advanced
charging algorithm and the measured temperature.
Chapter 2
Protections
Protections
SLUUCO0 – APRIL 2022
BQ28Z610-R2
13
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