DS2760 Dallas Semiconducotr, DS2760 Datasheet - Page 7

• Manufacturer Part Number: DS2760
• Description: High Precision Li-Ion Battery Monitor
• Manufacturer: Dallas Semiconducotr

Undervoltage. If the voltage of the cell drops below undervoltage threshold V
undervoltage delay t
Protection Register, and enters Sleep Mode.
Overcurrent, Charge Direction. The voltage difference between the IS1 pin and the IS2 pin (V
– V
V
COC flag in the Protection Register. The charge current path is not re-established until the voltage on the
PLS pin drops below VDD – V
pull PLS down when the offending charge current source has been removed.
Overcurrent, Discharge Direction. If V
shuts off the external discharge FET and sets the DOC flag in the Protection Register. The discharge
current path is not re-established until the voltage on PLS rises above VDD - V
a test current of value I
been removed.
Short Circuit. If the voltage on the SNS pin with respect to VSS exceeds short circuit threshold V
a period longer than short circuit delay t
DOC flag in the Protection Register. The discharge current path is not re-established until the voltage on
PLS rises above VDD - V
PLS up when the short circuit has been removed.
LITHIUM-ION PROTECTION CIRCUITRY EXAMPLE WAVEFORMS – Figure 3
discharge
OC
IS2
charge
for a period longer than overcurrent delay t
Sleep
Mode
) is the filtered voltage drop across the current sense resistor. If V
V
CELL
(1) To allow the device to react quickly to short circuits, detection is actually done on the SNS pin rather
CC
DC
V
IS
than on the filtered IS1 and IS2 pins. The actual short circuit detect condition is V
t
OVD
UVD
TST
t
SCD
, the DS2760 shuts off the charge and discharge FETs, sets the UV flag in the
TP
from VDD to PLS to pull PLS up when the offending low-impedance load has
. The DS2760 provides a test current of value I
(1)
TP
. The DS2760 provides a test current of value I
t
OVD
SCD
IS
, the DS2760 shuts off the external discharge FET and sets the
is less than -V
t
OCD
OCD
7 of 25
, the DS2760 shuts off both external FETs and sets the
t
OCD
OC
for a period longer than t
IS
t
exceeds overcurrent threshold
UVD
TST
SNS
UV
TP
from VDD to PLS to pull
TST
. The DS2760 provides
> V
for a period longer than
SC
from PLS to VSS to
.
OCD
-V
VSS
V
V
V
V
-V
V
VSS
VDD
active
inactive
0
OV
CE
UV
OC
PLS
, the DS2760
OC
SC
IS
DS2760
= V
SC
for
IS1