56
SLUUBD3D – September 2015 – Revised September 2018
Copyright © 2015–2018, Texas Instruments Incorporated
Power Modes
Chapter 8
SLUUBD3D – September 2015 – Revised September 2018
Power Modes
8.1
Introduction
To enhance battery life, the bq78350-R1 supports several power modes to minimize power consumption
during operation.
8.2
NORMAL Mode
In NORMAL mode, the device takes voltage, current, and temperature readings every 250 ms, performs
protection and gauging calculations, updates SBS data, and makes status readings at 1-s intervals.
Between these periods of activity, the device is in a reduced power state.
8.3
SLEEP Mode
8.3.1 Device Sleep
When the sleep conditions are met and the device is in REST (RELAX) mode, the device goes into
SLEEP mode with periodic wake-ups to reduce power consumption. The device returns to NORMAL mode
if any exit sleep condition is met.
(1)
DA Config[SLEEP]
and SMBus low are not checked if the
ManufacturerAccess()
SLEEP mode command is used to enter
SLEEP mode.
(2)
A wake on an SMBus command is only possible when the gas gauge is put to sleep using the
ManufacturerAccess()
SLEEP
mode command. Otherwise, the gas gauge wakes on an SMBus connection (clock or data high).
Status
Condition
Action
Activate
SMBus low for
BusTimeout
(1)
AND
DA Config[SLEEP]
= 1
(1)
AND
|
Current()
|
≤
Sleep Current
AND
Voltage Time
> 0 AND
OperationStatus()[SDM]
= 0 AND
No
PFAlert()
bits set AND
No
PFStatus()
bits set AND
No
SafetyAlert()
bits set AND
No [AOLD], [AOLDL], [ASCD], [ASCDL] set in
SafetyStatus()
Turn off CHG FET and PCHG FET if
FET
Options[SLEEPCHG]
= 0
Device goes to sleep.
Device wakes up every
Sleep:Voltage Time
period to
measure voltage and temperature.
Device wakes up every
Sleep:Current Time
period to
measure current.
Exit
SMBus connected
(1)
OR
SMBus command received
(2)
OR
DA Config[SLEEP]
= 1
(1)
OR
|
Current()
| >
Sleep Current
OR
Voltage Time
= 0 OR
OperationStatus()[SDM]
= 1 OR
PFAlert()
bits set OR
PFStatus()
bits set OR
SafetyAlert()
bits set OR
[AOLD], [AOLDL], [ASCD], [ASCDL]
set in
SafetyStatus()
Return to NORMAL mode
The configuration options for SLEEP are in the following data flash.
Class
Subclass
Name
Type
Min
Max
Default
Unit
Description
Power
Sleep
Sleep Current
I2
0
32767
10
mA
|
Current()
| threshold to enter SLEEP mode
Power
Sleep
Bus Timeout
U1
0
255
5
s
SMBus low time to enter SLEEP mode
Power
Sleep
Voltage Time
U1
0
255
5
s
Voltage sampling period in SLEEP mode
Power
Sleep
Current Time
U1
0
255
20
s
Current sampling period in SLEEP mode
