Texas Instruments BQ25120A User manual

BQ25121A Low IQ Highly Integrated Battery Charge Management Solution
for Wearables and IoT
1 Features
• Increases System Operation Time Between
Charges
– Configurable 300-mA Buck Regulator
(2.5-V Default)
– 700 nA (typical) Iq with Buck Converter
Enabled (No Load)
– Configurable Load Switch or 100mA LDO
Output (Load Switch by Default)
– Up to 300-mA Charge Current for Fast
Charging
– 0.5% Accurate Battery Voltage Regulation
(Configurable from 3.6 V to 4.65 V in 10-mV
Steps)
– Configurable Termination Current Down to
500 µA
– Simple Voltage Based Battery Monitor
– Watchdog Timer Disabled
• Highly Integrated Solution with Small Footprint
– 2.5 mm x 2.5 mm WCSP Package and 6
External Components for Minimal Solution
– Push-Button Wake-Up and Reset with
Adjustable Timers
– Power Path Management for Powering the
System and Charging the Battery
– Power Path Management enables <50 nA Ship
Mode Battery Quiescent Current for Longest
Shelf Life
– Battery Charger Operates from 3.4 V – 5.5 VIN
(5.5-V OVP / 20-V Tolerant)
– Dedicated Pins for Input Current Limit, Charge
Current, Termination Current, and Status
Output
• I2C Communication Control
– Charge Voltage and Current
– Termination Threshold
– Input Current Limit
– VINDPM Threshold
– Timer Options
– Load Switch Control
– System Output Voltage Adjustment
– LDO Output Voltage Adjustment
• Safety-Related Certification:
– TUV IEC 62368-1 Certification
2 Applications
• Smart Watches and other Wearable Devices
• Fitness Accessories
• Health Monitoring Medical Accessories
• Rechargeable Toys
3 Description
The BQ25121A is a highly integrated battery charge
management IC that integrates the most common
functions for wearable devices: Linear charger,
regulated output, load switch, manual reset with timer,
and battery voltage monitor. The integrated buck
converter is a high efficiency, low IQ switcher using
DCS-Control™ that extends light load efficiency down
to 10-µA load currents. The low quiescent current
during operation and shutdown enables maximum
battery life. The device supports charge currents from
5 mA to 300 mA.
Device Information
PART NUMBER PACKAGE(1) BODY SIZE (NOM)
BQ25121A DSBGA (25) 2.50 mm x 2.50 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
GND
HOST SDA
SCL
INT
SW
BAT
MR
BQ25121A
MCU /
SYSTEM
-+
NTC
TS
LS / LDO
<100mA
Load
IN
SYS
RESET
LSCTRL
VINLS
Unregulated
Load
PMID
PG
IPRETERM
ISET
ILIM
CD
IN
Simplified Schematic
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An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.

Table of Contents
1 Features............................................................................1
2 Applications..................................................................... 1
3 Description.......................................................................1
4 Revision History.............................................................. 2
5 Description (continued).................................................. 3
6 Device Comparison Table...............................................3
7 Pin Configuration and Functions...................................4
8 Specifications.................................................................. 6
8.1 Absolute Maximum Ratings........................................ 6
8.2 ESD Ratings............................................................... 6
8.3 Recommended Operating Conditions.........................6
8.4 Thermal Information....................................................7
8.5 Electrical Characteristics.............................................8
8.6 Timing Requirements................................................12
8.7 Typical Characteristics..............................................15
9 Detailed Description......................................................17
9.1 Overview................................................................... 17
9.2 Functional Block Diagram......................................... 17
9.3 Feature Description...................................................18
9.4 Device Functional Modes..........................................30
9.5 Programming............................................................ 32
9.6 Register Maps...........................................................35
10 Application and Implementation................................ 48
10.1 Application Information........................................... 48
10.2 Typical Application.................................................. 48
11 Power Supply Recommendations..............................63
12 Layout...........................................................................64
12.1 Layout Guidelines................................................... 64
12.2 Layout Example...................................................... 64
13 Device and Documentation Support..........................65
13.1 Device Support....................................................... 65
13.2 Receiving Notification of Documentation Updates..65
13.3 Trademarks.............................................................65
13.4 Support Resources................................................. 65
13.5 Electrostatic Discharge Caution..............................65
13.6 Glossary..................................................................65
14 Mechanical, Packaging, and Orderable
Information.................................................................... 65
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision * (April 2018) to Revision A (January 2021) Page
• Added Safety-Related Certification to Features................................................................................................. 1
• Added Device Comparison Table....................................................................................................................... 3
• Changed Storage Temperature.......................................................................................................................... 6
• Changed VD(PPM) to V(DPPM) .............................................................................................................................. 8
• Changed RDS(ON_LDO) ........................................................................................................................................ 8
• Changed Figure 8-2 .........................................................................................................................................12
• Deleted Update STAT to fault in VIN_UV actions in Fault and Status Condition Responses........................... 30
• Changed VIN_UV description...........................................................................................................................36
• Deleted I2C Address from title.......................................................................................................................... 39
• Changed reset state from 0100 1010 to 0100 0010......................................................................................... 47
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5 Description (continued)
The battery is charged using a standard Li-Ion charge profile with three phases: precharge, constant current and
constant voltage. A voltage-based JEITA compatible battery pack thermistor monitoring input (TS) is included
that monitors battery temperature and automatically changes charge parameters to prevent the battery from
charging outside of its safe temperature range. The charger is optimized for 5-V USB input, with 20-V tolerance
to withstand line transients. The buck converter is run from the input or battery. When in battery only mode, the
device can run from a battery up to 4.65 V.
A configurable load switch allows system optimization by disconnecting infrequently used devices. The manual
reset with timer allows multiple different configuration options for wake are reset optimization. A simple voltage
based monitor provides battery level information to the host in 2% increments from 60% to 100% of the
programmed V(BATREG).
6 Device Comparison Table
PART
NUMBER
DEFAULT
VINDPM
DEFAULT
SYS OUTPUT
DEFAULT
LDO OUTPUT
DEFAULT
VBATREG
DEFAULT
CHARGE
CURRENT
DEFAULT
TERMINATION
CURRENT
VDPPM WATCHDOG
BQ25120A Enabled 1.8 V Load Switch 4.2 V 10 mA 2 mA Enabled Enabled
BQ25121A Enabled 2.5 V Load Switch 4.2 V 10 mA 2 mA Enabled Disabled
BQ25122 Enabled 1.2 V Load Switch 4.2 V 11 mA 0.5 mA Enabled Enabled
BQ25125 Disabled 1.8 V 1.8 V (LDO) 4.2 V 10 mA 2 mA Disabled Enabled
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7 Pin Configuration and Functions
GND
RESETINT
MR
IPRETE
RM
ISET
BATBAT
TS
ILIM
PG
VINLS
VINLS
PGNDSWPMID
A
B
C
D
1 2 3 4
SDALSCTRLCD SCL
E
IN
LS/LDO
SYSPMID
GND
5
Figure 7-1. YFP Package 25-Pin DSBGA Top View
Table 7-1. Pin Functions
PIN I/O DESCRIPTION
NAME NO.
IN A2 I DC Input Power Supply. IN is connected to the external DC supply. Bypass IN to GND with
at least 1 µF of capacitance using a ceramic capacitor.
PMID A3, B3 I/O
High Side Bypass Connection. Connect at least 3µF of ceramic capacitance with DC bias
derating from PMID to GND as close to the PMID and GND pins as possible. When entering
Ship Mode, PMID is discharged by a 20-kΩ internal discharge resistor.
GND A1, D5 Ground connection. Connect to the ground plane of the circuit.
PGND A5 Power ground connection. Connect to the ground plane of the circuit. Connect the output
filter cap from the buck converter to this ground as shown in the layout example.
CD E2 I
Chip Disable. Drive CD low to place the part in High-Z mode with battery only present, or
enable charging when VIN is valid. Drive CD high for Active Battery mode when battery only
is present, and disable charge when VIN is present. CD is pulled low internally with 900 kΩ.
SDA E4 I/O I2C Interface Data. Connect SDA to the logic rail through a 10-kΩ resistor.
SCL E5 I I2C Interface Clock. Connect SCL to the logic rail through a 10-kΩ resistor.
ILIM C2 I
Adjustable Input Current Limit Programming. Connect a resistor from ILIM to GND to
program the input current limit. The input current includes the system load and the battery
charge current. Connect ILIM to GND to set the input current limit to the internal default
threshold. ILIM can also be updated through I2C.
LSCTRL E3 I Load Switch and LDO Control Input. Pull high to enable the LS/LDO output, pull low to
disable the LS/LDO output.
ISET C1 I
Fast-Charge Current Programming Input. Connect a resistor from ISET to GND to program
the fast-charge current level. Connect a resistor from ISET to GND to set the charge current
to the internal default. ISET can also be updated through I2C. While charging, the voltage at
ISET reflects the actual charging current and can be used to monitor charge current if an
ISET resistor is present and the device is not in host mode.
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Table 7-1. Pin Functions (continued)
PIN I/O DESCRIPTION
NAME NO.
IPRETERM D1 I
Termination current programming input. Connect a 0-Ω to 10-kΩ resistor from IPRETERM to
GND to program the termination current between 5% and 20% of the charge current. The
pre-charge current is the same as the termination current setting. Connect IPRETERM to
GND to set the termination current to the internal default threshold. IPRETERM can also be
updated through I2C.
INT D2 O
Status Output. INT is an open-drain output that signals charging status and fault interrupts.
INT pulls low during charging. INT is high impedance when charging is complete, disabled,
or the charger is in high impedance mode. When a fault occurs, a 128µs pulse is sent out as
an interrupt for the host. INT charge indicator function is enabled/disabled using the EN_INT
bit in the control register. Connect INT to a logic rail using an LED for visual indication of
charge status or through a 100kΩ resistor to communicate with the host processor.
PG D4 O
Open-drain Power Good status indication output. PG pulls to GND when VIN is above V(BAT)
+ VSLP and less that VOVP. PG is high-impedance when the input power is not within
specified limits. Connect PG to the desired logic voltage rail using a 1kΩ to 100kΩ resistor,
or use with an LED for visual indication. PG can also be configured as a push-button voltage
shifted output (MRS) in the registers, where the output of the PG pin reflects the status of
the MR input, but pulled up to the desired logic voltage rail using a 1kΩ to 100kΩ resistor.
RESET D3 O
Reset Output. RESET is an open drain active low output that goes low when MR is held low
for longer than tRESET, which is configurable by the MRRESET registers. RESET is
deasserted after the tRESET_D, typically 400ms.
MR E1 I
Manual Reset Input. MR is a push-button input that must be held low for greater than tRESET
to assert the reset output. If MR is pressed for a shorter period, there are two programmable
timer events, tWAKE1 and tWAKE2, that trigger an interrupt to the host. The MR input can also
be used to bring the device out of Ship mode.
SW A4 O Inductor Connection. Connect to the switched side of the external inductor.
SYS B5 I System Voltage Sense Connection. Connect SYS to the system output at the output bulk
capacitors. Bypass SYS locally with at least 4.7 µF of effective ceramic capacitance.
LS/LDO C5 O
Load Switch or LDO output. Connect 1 µF of effective ceramic capacitance to this pin to
assure stability. Be sure to account for capacitance bias voltage derating when selecting the
capacitor.
VINLS B4, C4 I Input to the Load Switch / LDO output. Connect 1 µF of effective ceramic capacitance from
this pin to GND.
BAT B1, B2 I/O Battery Connection. Connect to the positive terminal of the battery. Bypass BAT to GND with
at least 1 µF of ceramic capacitance.
TS C3 I
Battery Pack NTC Monitor. Connect TS to the center tap of a resistor divider from VIN to
GND. The NTC is connected from TS to GND. The TS function provides four thresholds for
JEITA compatibility. TS faults are reported by the I2C interface during charge mode.
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8 Specifications
8.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
MIN MAX UNIT
Input voltage
IN wrt GND –0.3 20 V
PMID, VINLS wrt GND –0.3 7.7 V
CD, SDA, SCL, ILIM, ISET, IPRETERM, LSCTRL,
INT, RESET, TS wrt GND –0.3 5.5 V
Output voltage SYS 3.6 V
Input current IN 400 mA
Sink current INT 10 mA
Sink/Source Current RESET 10 mA
Output Voltage Continuos SW –0.7 7.7 V
Output Current Continuous SW 400 mA
SYS, BAT 300 mA
Current LS/LDO 150 mA
BAT Operating Voltage VBAT, MR, 6.6 V
Junction Temperature –40 125 °C
Storage Temperature, Tstg –55 150 °C
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under
Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device
reliability.
8.2 ESD Ratings
VALUE UNIT
V(ESD) Electrostatic discharge
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2000
V
Charged device model (CDM), per JEDEC specification JESD22-
C101(2) ±500
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
8.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN NOM MAX UNIT
VIN
IN voltage range 3.4 5 20 V
IN operating voltage range, recommended 3.4 5 5.5
V(BAT) V(BAT) operating voltage range 5.5(1) V
V(VINLS) VINLS voltage range for Load Switch 0.8 5.5(2) V
V(VINLS) VINLS voltage range for LDO 2.2 5.5 V
IIN Input Current, IN input 400 mA
I(SW) Output Current from SW, DC 300 mA
I(PMID) Output Current from PMID, DC 300 mA
ILS/LDO Output Current from LS/LDO 100 mA
I(BAT), I(SYS) Charging and discharging using internal battery FET 300 mA
TJOperating junction temperature range –40 125 °C
(1) Any voltage greater than shown should be a transient event.
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(2) These inputs will support 6.6 V for less than 10% of the lifetime at V(BAT) or VIN, with a reduced current and/or performance.
8.4 Thermal Information
THERMAL METRIC(1)
BQ25121A
UNITYFP (DSBGA)
25 PINS
RθJA Junction-to-ambient thermal resistance 60 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 0.3 °C/W
RθJB Junction-to-board thermal resistance 12.0 °C/W
ψJT Junction-to-top characterization parameter 1.2 °C/W
ψJB Junction-to-board characterization parameter 12.0 °C/W
RθJC(bot) Junction-to-case (bottom) thermal resistance N/A °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
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8.5 Electrical Characteristics
Circuit of Figure 8-1, V(UVLO) < VIN < V(OVP) and VIN > V(BAT) + V(SLP), TJ = –40°C to 85°C and TJ = 25°C for typical values
(unless otherwise noted)
PARAMETERS TEST CONDITIONS MIN TYP MAX UNIT
INPUT CURRENTS
IIN
Supply Current for
Control
V(UVLO) < VIN < V(OVP) and VIN > V(BAT) + V(SLP) PWM
Switching, –40°C < TJ < 85°C 1 mA
V(UVLO) < VIN < V(OVP) and VIN > V(BAT) + V(SLP) PWM NOT
Switching 3 mA
0°C < TJ < 85°C, VIN = 5 V, Charge Disabled 1.5 mA
I(BAT_HIZ)
Battery discharge current
in High Impedance Mode
0°C < TJ < 60°C, VIN = 0 V, High-Z Mode, PWM Not
Switching, V(BUVLO) < V(BAT) < 4.65 V 0.7 1.2 µA
0°C < TJ < 60°C, VIN = 0 V, High-Z Mode, PWM Not
Switching, V(BUVLO) < V(BAT) < 6.6 V 0.9 1.5 µA
0°C < TJ < 60°C, VIN = 0 V or floating, High-Z Mode, PWM
Switching, No Load 0.75 3.5 µA
0°C < TJ < 85°C, VIN = 0 V, High-Z Mode, PWM Switching,
LSLDO enabled 1.35 4.25 µA
I(BAT_ACTIVE)
Battery discharge current
in Active Battery Mode
0°C < TJ < 85°C, VIN = 0 V, Active Battery Mode, PWM
Switching, LSLDO enabled, I2C Enabled, V(BUVLO) < V(BAT) <
4.65 V
6.8 12 µA
0°C < TJ < 85°C, 0 < VIN < VIN(UVLO), Active Battery Mode,
PWM Switching, LSLDO disabled, I2C Enabled, CD = Low,
V(BUVLO) < V(BAT) < 4.65 V
6.2 11 µA
I(BAT_SHIP)
Battery discharge current
in Ship Mode 0°C < TJ < 85°C, VIN = 0 V, Ship Mode 2 150 nA
POWER-PATH MANAGEMENT and INPUT CURRENT LIMIT
VDO(IN-PMID) VIN – V(PMID) VIN = 5 V, IIN = 300 mA 125 170 mV
VDO(BAT-PMID) V(BAT) – V(PMID) VIN = 0 V, V(BAT) > 3 V, Iff = 400 mA 120 160 mV
V(BSUP1)
Enter supplement mode
threshold V(BAT) > V(BUVLO)
V(PMID) <
V(BAT) – 25
mV
V
V(BSUP2)
Exit supplement mode
threshold V(BAT) > V(BUVLO)
V(PMID) <
V(BAT) –
5mV
V
I(BAT_OCP)
Current Limit, Discharge
Mode V(BAT) > V(BUVLO) 0.85 1.15 1.35 A
I(ILIM)
Input Current Limit Programmable Range, 50-mA steps 50 400 mA
Maximum Input Current
using ILIM
K(ILIM) /
R(ILIM)
IILIM accuracy IILIM
accuracy
50 mA to 100 mA –12% 12%
100 mA to 400 mA –5% 5%
K(ILIM)
Maximum input current
factor
I(ILIM) = 50 mA to 100 mA 175 200 225 AΩ
I(ILIM) = 100 mA to 400 mA 190 200 210 AΩ
VIN(DPM)
Input voltage threshold
when input current is
reduced
Programmable Range using VIN(DPM) Registers. Can be
disabled using VIN(DPM_ON)
4.2 4.9 V
VIN_DPM threshold
accuracy –3% 3%
BATTERY CHARGER
V(DPPM)
PMID voltage threshold
when charge current is
reduced
Above V(BATREG) 0.2 V
RON(BAT-PMID)
Internal Battery Charger
MOSFET on-resistance Measured from BAT to PMID, V(BAT) = 4.35 V, High-Z mode 300 400 mΩ
V(BATREG)
Charge Voltage Operating in voltage regulation, Programmable Range, 10-
mV steps 3.6 4.65 V
Voltage Regulation
Accuracy TJ = 0°C to 85°C –0.5% 0.5%
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8.5 Electrical Characteristics (continued)
Circuit of Figure 8-1, V(UVLO) < VIN < V(OVP) and VIN > V(BAT) + V(SLP), TJ = –40°C to 85°C and TJ = 25°C for typical values
(unless otherwise noted)
PARAMETERS TEST CONDITIONS MIN TYP MAX UNIT
I(CHARGE)
Fast Charge Current
Range V(BATUVLO) < V(BAT) < V(BATREG) 5 300 mA
Fast Charge Current
using ISET
K(ISET) /
R(ISET)
A
Fast Charge Current
Accuracy –5% 5%
K(ISET)
Fast Charge Current
Factor 5 mA > I(CHARGE) > 300 mA 190 200 210 AΩ
I(TERM)
Termination charge
current Termination current programmable range over I2C 0.5 37 mA
Termination Current
using IPRETERM
I(CHARGE) < 300 mA, R(ITERM) = 15 kΩ 5 % of ISET
I(CHARGE) < 300 mA, R(ITERM) = 4.99 kΩ 10 % of ISET
I(CHARGE) < 300 mA, R(ITERM) = 1.65 kΩ 15 % of ISET
I(CHARGE) < 300 mA, R(ITERM) = 549 Ω 20 % of ISET
Accuracy I(TERM) > 4 mA –10% 10%
tDGL(TERM) TERM deglitch time Both rising and falling, 2-mV over-drive, tRISE, tFALL = 100 ns 64 ms
I(PRE_CHARGE)
Pre-charge current Pre-charge current programmable range over I2C 0.5 37 mA
Pre-charge Current using
IPRETERM
I(TERM) A
Accuracy –10% 10%
V(RCH)
Recharge threshold
voltage Below V(BATREG) 100 120 140 mV
tDGL(RCHG)
Recharge threshold
deglitch time tFALL = 100 ns typ, V(RCH) falling 32 ms
SYS OUTPUT
RDS(ON_HS) PMID = 3.6 V, I(SYS) = 675 850 mΩ
RDS(ON_LS) PMID = 3.6 V, I(SYS) = 300 475 mΩ
RDS(CH_SYS)
MOSFET on-resistance
for SYS discharge VIN = 3.6 V, IOUT = –10 mA into VOUT pin 22 40 Ω
I(LIMF)
SW Current limit HS 2.2 V < V(PMID) < 5.5 V 450 600 675 mA
SW Current limit LS 2.2 V < V(PMID) < 5.5 V 450 700 850 mA
I(LIM_SS)
PMOS switch current limit
during softstart Current limit is reduced during softstart 80 130 200 mA
VSYS
SYS Output Voltage
Range Programmable range, 100 mV Steps 1.1 3.3 V
Output Voltage Accuracy VIN = 5 V, PFM mode, IOUT = 10 mA, V(SYS) = 1.8 V –2.5% 0 2.5%
DC Output Voltage Load
Regulation in PWM mode VOUT = 2 V, over load range 0.01 %/mA
DC Output Voltage Line
Regulation in PWM mode VOUT = 2 V, IOUT = 100 mA, over VIN range 0.01 %/V
LS/LDO OUTPUT
VIN(LS)
Input voltage range for
LS/LDO Load Switch Mode 0.8 6.6 V
Input voltage range for
LS/LDO LDO Mode 2.2 6.6 V
VOUT DC output accuracy TJ = 25°C –2% ±1% 2%
Over VIN, IOUT, temperature –3% ±2% 3%
VLDO Output range for LS/LDO Programmable Range, 0.1 V steps 0.8 3.3 V
ΔVOUT / Δ VIN
DC Line regulation VOUT(NOM) + 0.5 V < VIN < 6.6 V, IOUT = 5 mA –1% 1%
DC Load regulation 0 mA < IOUT < 100 mA –1% 1%
Load Transient 2 µA to 100 mA, VOUT = 1. 8 V –120 60 mV
RDS(ON_LDO) FET Rdson V(VINLS) = 3.6 V 570 800 mΩ
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8.5 Electrical Characteristics (continued)
Circuit of Figure 8-1, V(UVLO) < VIN < V(OVP) and VIN > V(BAT) + V(SLP), TJ = –40°C to 85°C and TJ = 25°C for typical values
(unless otherwise noted)
PARAMETERS TEST CONDITIONS MIN TYP MAX UNIT
R(DSCH_LSLDO)
MOSFET on-resistance
for LS/LDO discharge 1.7 V < V(VINLS) < 6.6 V, ILOAD = –10 mA 20 Ω
I(OCL_LDO)
Output Current Limit –
LDO VLS/LDO = 0 V 275 365 475 mA
I(LS/LDO) Output Current
V(VINLS) = 3.6 V, VLSLDO = 3.3 V 100 mA
V(VINLS) = 3.3 V, VLSLDO = 0.8 V 100 mA
V(VINLS) = 2.2 V, VLSLDO = 0.8 V 10 mA
IIN(LDO)
Quiescent current for
VINLS in LDO mode 0.9 µA
OFF-state supply current 0.25 µA
VIH(LSCTRL)
High-level input voltage
for LSCTRL 1.15 V > V(VINLS) > 6.6 V 0.75 x V(SYS)
6.6 V
VIL(LSCTRL)
Low-level input voltage
for LSCTRL 1.15 V > V(VINLS) > 6.6 V 0.25 x V(SYS)
V
PUSHBUTTON TIMER ( MR)
VIL Low-level input voltage VBAT > VBUVLO 0.3 V
RPU
Internal pull-up
resistance 120 kΩ
VBAT MONITOR
VBMON
Battery Voltage Monitor
Accuracy V(BAT) Falling - Including 2% increment –3.5 3.5 %V(BATREG)
BATTERY-PACK NTC MONITOR
VHOT
High temperature
threshold VTS falling, 1% VIN Hysteresis 14.5 15 15.2 %VIN
VWARM
Warm temperature
threshold VTS falling, 1% VIN Hysteresis 20.1 20.5 20.8 %VIN
VCOOL
Cool temperature
threshold VTS rising, 1% VIN Hysteresis 35.4 36 36.4 %VIN
VCOLD
Low temperature
threshold VTS rising, 1% VIN Hysteresis 39.3 39.8 40.2 %VIN
TSOFF TS Disable threshold VTS rising, 2% VIN Hysteresis 55 60 %VIN
PROTECTION
V(UVLO)
IC active threshold
voltage VIN rising 3.4 3.6 3.8 V
VUVLO(HYS) IC active hysteresis VIN falling from above VUVLO 150 mV
V(BUVLO)
Battery Undervoltage
Lockout threshold Range
Programmable Range for V(BUVLO) VBAT falling, 150 mV
Hysteresis 2.2 3.0 V
Default Battery
Undervoltage Lockout
Accuracy
V(BAT) falling –2.5% 2.5%
V(BATSHORT)
Battery short circuit
threshold Battery voltage falling 2 V
V(BATSHORT_HYS)
Hysteresis for
V(BATSHORT)
100 mV
I(BATSHORT)
Battery short circuit
charge current I(PRETERM) mA
V(SLP)
Sleep entry threshold, VIN
– V(BAT)
2 V < VBAT < V(BATREG), VIN falling 65 120 mV
V(SLP_HYS)
Sleep-mode exit
hysteresis VIN rising above V(SLP) 40 65 100 mV
VOVP
Maximum Input Supply
OVP threshold voltage VIN rising, 100 mV hysteresis 5.35 5.55 5.75 V
tDGL_OVP
Deglitch time, VIN OVP
falling VIN falling below VOVP, 1V/us 32 ms
TSHTDWN Thermal trip VIN > VUVLO 114 °C
BQ25121A
SLUSDA7A – APRIL 2018 – REVISED JANUARY 2021 www.ti.com
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