Datasheet

whenever the NAC registers are counting at a rate equiva
-
lent to |V
SRO
|
≥
4mV. When pulled low, the segment out
-
puts become active immediately. A capacitor tied to DISP
allows the display to remain active for a short period of
time after activation by a push-button switch.
The segment outputs are modulated as two banks of
three, with segments 1, 3, and 5 alternating with seg
-
ments 2, 4, and 6. The segment outputs are modulated
at approximately 100Hz with each segment bank active
for 30% of the period.
SEG
1
blinks at a 4Hz rate whenever V
SB
has been de
-
tected to be below V
EDV1
(EDV1 = 1), indicating a low-
battery condition. V
SB
below V
EDVF
(EDVF = 1) disables
the display output.
Microregulator
The bq2010 can operate directly from 3 or 4 cells. To fa
-
cilitate the power supply requirements of the bq2010, an
REF output is provided to regulate an external low-
threshold n-FET. A micropower source for the bq2010
can be inexpensively built using the FET and an exter
-
nal resistor; see Figure 1.
15
Absolute Maximum Ratings
Symbol Parameter Minimum Maximum Unit Notes
V
CC
Relative to V
SS
-0.3 +7.0 V
All other pins Relative to V
SS
-0.3 +7.0 V
REF Relative to V
SS
-0.3 +8.5 V
Current limited by R1 (see Figure 1)
V
SR
Relative to V
SS
-0.3 +7.0 V
Minimum 100
Ω
series resistor should
be used to protect SR in case of a
shorted battery (see the bq2010 appli-
cation note for details).
T
OPR
Operating tempera-
ture
0 +70 °C
Commercial
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 condi-
tions beyond the operational limits for extended periods of time may affect device reliability.
DC Voltage Thresholds (T
A
= T
OPR
; V = 3.0 to 6.5V)
Symbol Parameter Minimum Typical Maximum Unit Notes
V
EDVF
Final empty warning
0.93 0.95 0.97 V
SB
V
EDV1
First empty warning
1.03 1.05 1.07 V
SB
V
SR1
Discharge compensation threshold
-120 -150 -180 mV
SR, V
SR
+ V
OS
V
SRO
SR sense range
-300 - +2000 mV
SR, V
SR
+ V
OS
V
SRQ
Valid charge
375 - -
µ
VV
SR
+ V
OS
(see note)
V
SRD
Valid discharge
- - -300
µ
VV
SR
+ V
OS
(see note)
V
MCV
Maximum single-cell voltage
2.20 2.25 2.30 V
SB
V
BR
Battery removed/replaced
- 0.1 0.25 V
SB pulled low
2.20 2.25 2.30 V
SB pulled high
Note: Default value; value set in DMF register. V
OS
is affected by PC board layout. Proper layout guidelines
should be followed for optimal performance. See “LayoutConsiderations.”
bq2010