Datasheet

LTC2941
3
2941fa
elecTrical characTerisTics
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 2)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
BAT
Alert V
BAT
Alert Threshold V
SENSE
+
Falling, B[7:6] = 01
l
2.75 2.8 2.85 V
V
SENSE
+
Falling, B[7:6] = 10
l
2.85 2.9 2.95 V
V
SENSE
+
Falling, B[7:6] = 11
l
2.95 3 3.05 V
Digital Inputs and Digital Outputs
V
ITH
Logic Input Threshold, AL/CC, SCL,
SDA
l
0.3 •
V
SENSE
+
0.7 •
V
SENSE
+
V
V
OL
Low Level Output Voltage, AL/CC, SDA I = 3mA
l
0.4 V
I
IN
Input Leakage, AL/CC, SCL, SDA V
IN
= V
SENSE
+
/2
l
1 µA
C
IN
Input Capacitance, AL/CC, SCL, SDA (Note 7)
l
10 pF
t
PCC
Minimum Charge Complete (CC) Pulse
Width
1 µs
I
2
C Timing Characteristics
f
SCL(MAX)
Maximum SCL Clock Frequency
l
400 900 kHz
t
BUF(MIN)
Bus Free Time Between STOP/START
l
1.3 µs
t
SU,STA(MIN)
Minimum Repeated START Set-Up
Time
l
600 ns
t
HD,STA(MIN)
Minimum Hold Time (Repeated)
START Condition
l
600 ns
t
SU,STO(MIN)
Minimum Set-Up Time for STOP
Condition
l
600 ns
t
SU,DAT(MIN)
Minimum Data Set-Up Time Input
l
100 ns
t
HD,DATI(MIN)
Minimum Data Hold Time Input
l
0 µs
t
HD,DATO
Data Hold Time Output
l
0.3 0.9 µs
t
Of
Data Output Fall Time (Notes 6, 7)
l
20 + 0.1
• C
B
300 ns
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: All currents into pins are positive, all voltages are referenced to
GND unless otherwise specified
Note 3: I
SUPPLY
= I
SENSE
+
+ I
SENSE
–
Note 4: The equivalent charge of an LSB in the accumulated charge
registers (C, D) depends on the value of R
SENSE
and the setting of the
internal prescaling factor M. It is calculated by:
q
LSB
= 0.085mAh •
50mΩ
R
SENSE
•
M
128
See Choosing R
SENSE
and Coulomb Counter Prescaler M section for more
information.
1mAh = 3.6A • s = 3.6C (coulomb), 0.085mAh = 306mC.
Note 5: Deviation of q
LSB
from its nominal value.
Note 6: C
B
= capacitance of one bus line in pF (10pF ≤ C
B
≤ 400pF).
Note 7: Guaranteed by design, not subject to test.