BQ77904_017 Datasheet, PDF (1/47 Pages) Texas Instruments – 3-5S Ultra Low-Power Voltage, Current, Temperature, and Open Wire Stackable Lithium-ion Battery Protector

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bq77904, bq77905
SLUSCM3G – JUNE 2016 – REVISED SEPTEMBER 2017
bq77905, bq77904 3-5S Ultra Low-Power Voltage, Current, Temperature,
and Open Wire Stackable Lithium-ion Battery Protector
1 Features
•1 Normal Mode: 6 µA (bq77904 and bq77905)
• Full Suite of Voltage, Current and Temperature
Protections
• Scalable Cell Count From 3 S to 20 S or More
• Voltage Protection (Accuracy ±10 mV)
– Overvoltage: 3 V to 4.575 V
– Undervoltage: 1.2 V to 3 V
• Open Cell and Open Wire Detection (OW)
• Current Protection
– Overcurrent Discharge 1: –10 mV to –85 mV
– Overcurrent Discharge 2: –20 mV to +170 mV
– Short Circuit Discharge: –40 mV to +340 mV
– Accuracy ±20% for ≤ 20 mV, ±30% for > 20
mV Across Full Temperature
• Temperature Protection
– Overtemperature Charge: 45°C or 50°C
– Overtemperature Discharge: 65°C or 70°C
– Undertemperature Charge: –5°C or 0°C
– Undertemperature Discharge: –20°C or –10°C
• Additional Features
– Independent Charge (CHG) and Discharge
(DSG) FET Drivers
– 36-V Absolute Maximum Rating Per Cell Input
– Built-In-Self-Test Functions For High Reliability
• Shutdown Mode: 0.5 µA Maximum
Simplified Schematic
VDD
VTB
VC5
TS
bq77094/5
LD
Vss
SRP SRN DSG CHGU
PACK+
2 Applications
• Power Tools, Garden Tools
• Start-Stop Battery Packs
• Lead-Acid (PbA) Replacement Batteries
• Light Electric Vehicles
• Energy Storage Systems, Uninterruptible Power
Supplies (UPS)
• 10.8 V to 72 V Packs
3 Description
The bq77904 and bq77905 devices are low-power
battery pack protectors that implement a suite of
voltage, current, and temperature protections without
microcontroller (MCU) control. The device's stackable
interface provides simple scaling to support battery
cell applications from 3 S to 20 S or more. Protection
thresholds and delays are factory-programmed and
available in a variety of configurations. Separate
overtemperature and undertemperature thresholds for
discharge (OTD and UTD) and charge (OTC and
UTC) are provided for added flexibility.
The device achieves pack protection through the
integrated independent CHG and DSG low-side
NMOS FET drivers, which may be disabled through
two control pins. These control pins may also be used
to achieve cell protection solutions for higher series
(6 S and beyond) in a simple and economical
manner. To do this, simply cascade a higher device
CHG and DSG outputs to the immediate lower device
control pins. For reduced component count, all
protection faults use internal delay timers.
Device Information⁽¹⁾
PART NUMBER
PACKAGE
BODY SIZE (NOM)
bq77904
bq77905
TSSOP (20)
6.50 mm × 4.40 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
VDD
CTRD
CTRC
VTB
VC5
TS
bq77094/5
Vss
SRP
SRN
DSG
LD
CHG
PACK-
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1
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.