SLUUCP8 June 2024 BQ41Z50
The BQ41Z50 device can detect cell overvoltage in batteries and protect cells from damage by preventing further charging.
The protection detection threshold may be influenced by the temperature settings of the advanced charging algorithm and the measured temperature. Additionally, this protection feature can be enabled to create a PF by setting the [COVL] bit in the Enabled PF A register.
| Status | Condition | Action |
|---|---|---|
| Normal, ChargingStatus()[UT] or [LT] = 1 | Max cell voltage1..4 < COV:Threshold Low Temp | SafetyAlert()[COV] = 0 PFAlert()[COVL] = 0 Decrement COVL counter by one after each COV:Counter Dec Delay period if COVL counter > 0 |
| Normal, ChargingStatus()[STL] = 1 | Max cell voltage1..4 < COV:Threshold Standard Temp Low | |
| Normal, ChargingStatus()[STH] = 1 | Max cell voltage1..4 < COV:Threshold Standard Temp High | |
| Normal, ChargingStatus()[RT] = 1 | Max cell voltage1..4 < COV:Threshold Rec Temp | |
| Normal, ChargingStatus()[HT] or [OT] = 1 | Max cell voltage1..4 < COV:Threshold High Temp | |
| Alert, ChargingStatus()[UT] or [LT] = 1 | Max cell voltage1..4 ≥ COV:Threshold Low Temp | SafetyAlert()[COV] = 1 BatteryStatus()[TCA] = 1 |
| Alert, ChargingStatus()[STL] = 1 | Max cell voltage1..4 ≥ COV:Threshold Standard Temp Low | |
| Alert, ChargingStatus()[STH] = 1 | Max cell voltage1..4 ≥ COV:Threshold Standard Temp High | |
| Alert, ChargingStatus()[RT] = 1 | Max cell voltage1..4 ≥ COV:Threshold Rec Temp | |
| Alert, ChargingStatus()[HT] or [OT] = 1 | Max cell voltage1..4 ≥ COV:Threshold High Temp | |
| Trip, ChargingStatus()[UT] or [LT] = 1 | Max cell voltage1..4 ≥ COV:Threshold Low Temp for COV:Delay duration | SafetyAlert()[COV] = 0 SafetyStatus()[COV] = 1 BatteryStatus()[TCA] = 0 OperationStatus()[XCHG] = 1 Increment COVL counter |
| Trip, ChargingStatus()[STL] = 1 | Max cell voltage1..4 ≥ COV:Threshold Standard Temp Low for COV:Delay duration | |
| Trip, ChargingStatus()[STH] = 1 | Max cell voltage1..4 ≥ COV:Threshold Standard Temp High for COV:Delay duration | |
| Trip, ChargingStatus()[RT] = 1 | Max cell voltage1..4 ≥ COV:Threshold Rec Temp for COV:Delay duration | |
| Trip, ChargingStatus()[HT] or [OT] = 1 | Max cell voltage1..4 ≥ COV:Threshold High Temp for COV:Delay duration | |
| Recovery, ChargingStatus()[UT] or [LT] = 1 | SafetyStatus()[COV] = 1 AND Max cell voltage1..4 ≤ COV:Recovery Low Temp | SafetyStatus()[COV] = 0 BatteryStatus()[TCA] = 0 OperationStatus()[XCHG] = 0 |
| Recovery, ChargingStatus()[STL] = 1 | SafetyStatus()[COV] = 1 AND Max cell voltage1..4 ≤ COV:Recovery Standard Temp Low | |
| Recovery, ChargingStatus()[STH] = 1 | SafetyStatus()[COV] = 1 AND Max cell voltage1..4 ≤ COV:Recovery Standard Temp High | |
| Recovery, ChargingStatus()[RT] = 1 | SafetyStatus()[COV] = 1 AND Max cell voltage1..4 ≤ COV:Recovery Rec Temp | |
| Recovery, ChargingStatus()[HT] or [OT] = 1 | SafetyStatus()[COV] = 1 AND Max cell voltage1..4 ≤ COV:Recovery High Temp | |
| Latch Alert | COVL counter > 0 | SafetyAlert()[COVL] = 1 if EnabledProtections[COVL] is set. PFAlert()[COVL] = 1 if EnabledPF[COVL] is set |
| Latch Trip | COVL counter ≥ COV:Latch limit | SafetyStatus()[COVL] = 1 if EnabledProtections[COVL] is set PFStatus()[COVL] = 1 if EnabledPF[COVL] is set. PFAlert()[COVL] = 0 SafetyAlert()[COVL] = 0 OperationStatus()[XCHG] = 1 |
| Latch Reset([NR]=0) | SafetyStatus()[COVL] = 1 AND DA Configuration[NR] = 0 AND Low-high-low transition on PRES pin | SafetyStatus()[COVL] = 0 Reset COVL counter. OperationStatus[XCHG] = 0 if SafetyStatus()[COV] = 0 |
| Latch Reset([NR]=1) | (SafetyStatus()[COVL] = 1 AND DA Configuration[NR]=1 for COV:Reset time | SafetyStatus()[COVL] = 0 Reset COVL counter. OperationStatus[XCHG] = 0 if SafetyStatus()[COV] = 0 |