17
SLUUBD3D – September 2015 – Revised September 2018
Copyright © 2015–2018, Texas Instruments Incorporated
Protections
Chapter 3
SLUUBD3D – September 2015 – Revised September 2018
Protections
3.1
Introduction
The bq78350-R1 supports a wide range of battery and system protection features that are easily
configured or enabled via the integrated data flash. All of the protection items can be enabled or disabled
under
Settings:Enable Protections A
,
Settings:Enable Protections B
, and
Settings:Enable
Protections C
.
If the CHG FET is off and the gauge detects discharge current
≥
Dsg Current Threshold
, then the CHG
FET is turned on to protect CHG FET body diode. The CHG FET is turned back off once discharge current
is removed. If the DSG FET is off and the gauge detects charge current
≥
Chg Current Threshold
, then
the DSG FET is turned on to protect the DSG FET body diode. The DSG FET is turned back off once
charge current is removed. Body diode protection is always active.
3.1.1 General Protections Configuration
Class
Subclass
Name
Format
Size in
Bytes
Min
Max
Default
Unit
Settings
Protection
Protection
Configuration
Hex
1
0x00
0xFF
0x00
—
7
6
5
4
3
2
1
0
RSVD
RSVD
CC_DSG_OFF
DC_CHG_OFF
LPEN
VAUXR
CUV_RECOV_
CHG
RSVD
RSVD (Bits 7–6)
: Reserved
CC_DSG_OFF (Bit 5)
: Turns DSG FET OFF in current-based charge faults
0 = Disabled (default)
1 = Enabled
DC_CHG_OFF (Bit 4)
: Turns CHG FET OFF in current-based discharge faults
0 = Disabled (default)
1 = Enabled
LPEN (Bit 3)
: Protection recovery uses the LOAD_PRESENT flag in the AFE to determine discharge
fault recovery. LOAD_PRESENT should only be used in a low-side protection FET configuration.
0 = Disabled (default)
1 = Enabled
VAUXR (Bit 2)
: Protection recovery uses the VAUX input as charger present detection.
0 = Disabled (default)
1 = Enabled
CUV_RECOV_CHG (Bit 1)
: Requires charge to recover
SafetyStatus()[CUV]
0 = Disabled (default)
1 = Enabled
RSVD (Bit 0)
: Reserved