Features
Complete bq2050 Power Gauge solution for Li-Ion
battery packs
Battery information available over a single-wire
bidirectional serial port
Battery state-of-charge monitoring for 2- to 4-cell
series applications
On-board regulator allows direct connection to the
battery
"L" version includes push-button activated LEDs to
display state-of-charge information
Nominal capacity pre-configured
Compact size for battery pack integration
General Description
The bq2150 Power Gauge Module provides a complete and
compact solution for capacity monitoring of Li-Ion battery
packs. Designed for battery pack integration, the bq2150
incorporates a bq2050 Gas Gauge IC, a current sense re-
sistor, and all other components necessary to accurately
monitor and display the capacity of 2 to 4 series cells.
The bq2150L includes five LEDs to display remaining ca-
pacity in 20% increments of the learned capacity.
The
LEDs are activated with the onboard push-button switch.
Contacts are provided on the bq2150 for direct connec-
tion to the battery stack (BAT+, BAT-) and the serial
communications port (DQ). The RBI input provides
backup power to the bq2050 in the event that the cells
are removed or the battery is turned off. The bq2150
has a 1
F capacitor onboard connected to RBI to supply
backup power for about an hour. In battery packs that
use high-side FETs to control the charge/discharge of
the Li-Ion cells, the RBI input can be wired to a single
cell to provide prolonged data retention times. The SD
input allows an external signal (active low) to turn the
bq2050 IC off to minimize internal current consumption
of the battery pack and maximize storage life of the pack
in the system.
When turned off, the bq2050 is non-
functional, and the RBI power source maintains register
information. Please refer to the bq2050 data sheet for
the specifics on the operation of the gas gauge.
Unitrode configures the bq2150 based on the informa-
tion requested in Table 1. The configuration defines the
number of series cells, the nominal battery pack capac-
ity, and the Li-Ion battery type (coke or graphite anode).
Figure 1 shows how the module connects to the cells.
A module development kit is also available for the
bq2150. The bq2150B-KT or the bq2150LB-KT includes
one configured module and the following:
1)
An interface board that allows connection to the se-
rial port of an AT-compatible computer.
2)
Menu-driven software to display charge/discharge
activity and to allow user interface to the bq2050
from any standard DOS PC.
3)
Source code for the TSR.
Pin Descriptions
P1
DQ/Serial Communications port
P2
No connect
P3
BAT+/Battery positive/pack positive
P4
SD/Shutdown
P5
RBI/Register backup input
P6
GND/Ground
P7
PACK-/Pack negative
P8
BAT-/Battery negative
1
Li-Ion Power GaugeTM Module
bq2150
5/99 B
2
bq2150
Customer Name: ___________________________________________________________________________
Contact: _________________________________________
Phone: ______________________________
Address: _________________________________________________________________________________
_________________________________________________________________________________
Sales Contact: ____________________________________
Phone: ______________________________
Number of series battery cells (2-4)
____________________
Coke or graphite cell anode
____________________
Battery pack capacity (mAh)
____________________
Discharge rate into load (3.0A max)
Min. ________ Avg. _________ Max. _________
Charge rate (3.0A max)
____________________
Nominal Available Capacity after reset
(Programmed Capacity or Zero)
____________________
Self-discharge compensation (Y/N)
____________________
LEDs and switch (Y/N)
____________________
FAE Approval: _____________________________________
Date:________________________________
Table 1. bq2150 Module Configuration
FG-9611
Charger
Load
P8
P7
P3
bq2150
Cells
Battery Pack
PACK+
PACK-
Figure 1. Module Connection Diagram
4
bq2150 Board
bq2150
5
Absolute Maximum Ratings
Symbol
Parameter
Minimum
Maximum
Unit
Conditions
V
CC
Relative to V
SS
-0.3
+7.0
V
bq2050
All other pins
Relative to V
SS
-0.3
+7.0
V
bq2050
P
SR
Continuous sense resis-
tor power dissipation
-
3
W
Thru-hole sense resistor
-
1
W
Surface-mount sense resistor
I
CHG
Continuous charge/dis-
charge current
-
3.0
A
T
OPR
Operating temperature
0
+70
C
Commercial
T
STR
Storage temperature
-40
+85
C
Note:
Permanent device damage may occur if Absolute Maximum Ratings are exceeded. Functional operation
should be limited to the Recommended DC Operating Conditions detailed in this data sheet. Exposure to con-
ditions beyond the operational limits for extended periods of time may affect device reliability.
DC Electrical Characteristics
(TA = TOPR)
Symbol
Parameter
Minimum
Typical
Maximum
Unit Conditions/Notes
NumCell
Number of series cells in
battery pack
2
-
4
-
BAT+
Positive terminal of pack
GND
NumCell
3.6V
*
NumCell
5.4V
*
V
BAT-
Negative terminal of pack
GND - 0.3
-
GND+2.0
V
I
CC
Supply current at BAT
1P
terminal (no external
loads)
-
200
300
A
R
DQ
Internal pull-down
500k
-
-
1
I
OL
Open-drain sink current
DQ
-
-
5.0
mA
1
V
OL
Open-drain output low, I
OL
DQ
-
-
0.5
V
1
I
OL
< 5mA
V
IHDQ
DQ input high
2.5
-
-
V
1
V
ILDQ
DQ input low
-
-
0.8
V
1
V
OS
Voltage offset
-
-
150
V
1
Note:
1. Characterized on PCB, IC 100% tested.
bq2150
6
LED Option:
L = LEDs plus switch
Blank = No LEDs or switch
Notes:
1.
Requires configuration sheet (Table 1)
2.
Example production part number: bq2150LB-001
DC Voltage Thresholds
(TA = TOPR)
Symbol
Parameter
Minimum
Typical
Maximum
Unit
Notes
V
EDVF
Final empty warning
1.45
1.47
1.49
V
BAT+/(2*NumCell)
1
V
EDV1
First empty warning
1.50
1.52
1.55
V
BAT+/(2*NumCell)
1
V
MCV
Maximum single-cell voltage
2.20
2.25
2.30
V
BAT+/(2*NumCell)
1
V
SRO
Sense range
-300
-
+2000
mV
SR, V
SR
+ V
OS2
V
SRQ
Valid charge
210
-
-
V
V
SR
+ V
OS 2, 3
V
SRD
Valid discharge
-
-
-200
V
V
SR
+ V
OS 2, 3
Notes:
1.
At SB input of bq2050
2.
At SR input of bq2050.
3.
Default value; value set in DMF register.
Ordering Information
bq2150
bq2150
B --
Customer Code:
Blank = Sample or Pre-production
1
KT = Evaluation system
XXX = Customer-specific; assigned by Unitrode
2
Package Option:
B = Board-level product
Device:
Li-Ion Power Gauge Module
Change No.
Page No.
Description
1
2
Updated Table 1 to include 3.0A limit
1
5
Added 3.0A maximum continuous charge/discharge current specification
Note:
Change 1 = May 1999 B changes from April 1999.
Data Sheet Revision History
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