SHUTDOWN MODE
Charger detect on
TS2 pulldown detect on
NORMAL MODE
Monitoring on
Protection on
REG18,
REG1, REG2
on
SLEEP MODE
REG18,
REG1, REG2
on
Comparator protections on
Periodic ADC protections on
Current wake detector on
Charger
detection or TS2
pulldown
detection
Shutdown signal by
RST_SHUT pin or
command or low
V
BAT
or high temp
Shutdown signal by
RST_SHUT pin or
low V
BAT
or high
temp
Very low V
BAT
EXIT_DEEPSLEEP()
command or reset
signal by RST_SHUT pin or charger
detected
DEEPSLEEP()
command
twice, or
Permanent Fail
SLEEP_DISABLE()
command or fault or fault recovery
or
current detected
or
charger detected
or reset signal
by RST_SHUT pin
Low current
Reset signal by RST_SHUT
pin
Blue = programmable
DEEPSLEEP MODE
REG18,
REG1, REG2
on
LFO on
DEEPSLEEP()
command twice
Figure 13-1. Device Functional Modes
13.2 NORMAL Mode
NORMAL mode is the highest performance mode of the device, in which the device makes regular
measurements of voltage, current, and temperature, the LFO (low frequency oscillator) is operating, and the
internal processor powers up (as needed) for data processing and control. Full battery protections are operating,
based on device configuration settings. System current is measured at intervals of 3 ms, with cell voltages
measured at intervals of 63 ms or slower, depending on the configuration. The device also provides a
configuration bit that causes the conversion speed for both voltages and CC2 Current to be doubled, with a
reduction in measurement resolution.
The device is generally in NORMAL mode when any active charging or discharging is underway. When the CC1
Current measurement falls below a programmable current threshold, the system is considered in RELAX mode,
and the BQ769142 device can autonomously transition into SLEEP mode, depending on the configuration.
13.3 SLEEP Mode
SLEEP mode is a reduced functionality state that can be optionally used to reduce power dissipation when there
is little or no system load current or charging in progress, but still provides voltage at the battery pack terminals
to keep the system alive. At initial power up, a configuration bit determines whether the device can enter SLEEP
mode. After initialization, SLEEP mode can be allowed or disallowed using subcommands. Status bits are
provided to indicate whether the device is presently allowed to enter SLEEP mode or not, and whether it is
presently in SLEEP mode or not.
When the magnitude of the CC1 Current measurement falls below a programmable current threshold, the
system is considered in relax mode, and the BQ769142 device will autonomously transition into SLEEP mode, if
settings permit. During SLEEP mode, comparator-based protections operate the same as during NORMAL
mode. ADC-based current, voltage, and temperature measurements are taken at programmable intervals. All
temperature protections use the ADC measurements taken at these intervals, so they will update at a reduced
rate during SLEEP mode.
The BQ769142 device exits SLEEP mode if a protection fault occurs, if current begins flowing, if a charger is
attached, if forced by a subcommand, or if the RST_SHUT pin is asserted for less than 1 second. When exiting
SLUSE91A – SEPTEMBER 2020 – REVISED FEBRUARY 2021
Copyright © 2021 Texas Instruments Incorporated
49
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