ds2760bx-025-t-r Maxim Integrated Products, Inc., ds2760bx-025-t-r Datasheet - Page 7

• Manufacturer Part Number: ds2760bx-025-t-r
• Description: Ds2760 High-precision Li+ Battery Monitor
• Manufacturer: Maxim Integrated Products, Inc.

charge FET back on (unless another protection condition prevents it). Discharging remains enabled
during overvoltage.
Undervoltage. If the voltage of the cell drops below undervoltage threshold V
undervoltage delay t
Protection Register, and enters Sleep Mode. The DS2760 provides a current-limited (I
charge path from PLS to VDD to gently charge severely depleted cells. The recovery path is enabled
when 0 £ VDD < 3V(typ). Once VDD reaches 3V(typ), the DS2760 will return to normal operation,
awaiting connection of a charger to turn on the charge FET and pull out of 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 V
pull PLS down in order to detect the removal of the offending charge current source.
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 V
test current of value I
low-impedance load.
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 V
PLS up in order to detect the removal of the short circuit.
LITHIUM-ION PROTECTION CIRCUITRY EXAMPLE WAVEFORMS Figure 3
discharge
OC
IS2
charge
for a period longer than overcurrent delay t
Sleep
Mode
V
) is the filtered voltage drop across the current sense resistor. If 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
DD
UVD
TST
– V
t
DD
SCD
, the DS2760 shuts off the charge and discharge FETs, sets the UV flag in the
from V
TP
– V
. The DS2760 provides a test current of value I
TP
(1)
. The DS2760 provides a test current of value I
DD
to PLS to pull PLS up in order to detect the removal of the offending
t
OVD
SCD
IS
, the DS2760 shuts off the external discharge FET and sets the
is less than –V
t
OCD
OCD
, the DS2760 shuts off both external FETs and sets the
7
t
OCD
OC
for a period longer than t
DD
IS
– V
t
exceeds overcurrent threshold
UVD
TST
TP
UV
SNS
. The DS2760 provides a
from V
TST
for a period longer than
> V
from PLS to VSS to
SC
.
DD
OCD
-V
VSS
V
V
V
V
-V
V
VSS
VDD
active
inactive
0
to PLS to pull
OV
CE
UV
OC
PLS
, the DS2760
OC
SC
RC
) recovery
IS
= V
SC
for
IS1