DS2778G+T&R Maxim Integrated Products, DS2778G+T&R Datasheet - Page 14

• Manufacturer Part Number: DS2778G+T&R
• Description: IC FUEL GAUGE LI+ 2CELL 14-TDFN
• Manufacturer: Maxim Integrated Products

Specifications of DS2778G+T&R

• Function: Fuel, Gas Gauge/Monitor
• Battery Type: Lithium-Ion (Li-Ion), Lithium-Polymer (Li-Pol)
• Voltage - Supply: 4 V ~ 9.2 V
• Operating Temperature: -20°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 14-TDFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2-Cell, Stand-Alone, Li+ Fuel-Gauge IC with
Protector and Optional SHA-1 Authentication
If the average of the voltages on (V
(V
V
the DS2775–DS2778 shut off the charge and discharge
FETs. If UVEN is set, the DS2775–DS2778 also enter
sleep mode. When a charger is detected and V
V
recovery charge path (I
charge severely depleted cells. The recovery charge
path is enabled when 0 ≤ [(V
V
(V
Charge current develops a negative voltage on V
with respect to V
overcurrent threshold, V
overcurrent delay, t
both external FETs. The charge current path is not re-
established until the voltage on the PLS pin drops
below (V
current of value I
down, in order to detect the removal of the offending
charge current source.
Discharge current develops a positive voltage on V
with respect to V
overcurrent threshold, V
t
charge FET. The discharge current path is not reestab-
lished until the voltage on PLS rises above (V
Figure 4. Voltage Register Format
14
OCD
UV
IN2
SS
IN1
IN1
)] < V
, for a period longer than undervoltage delay, t
, the DS2775–DS2778 provide a current-limited
Overcurrent, Discharge Direction (DOC)
MSb
“S”: SIGN BIT(S), “X”: RESERVED
______________________________________________________________________________________
, the DS2775–DS2778 shut off the external dis-
- V
S
- V
Overcurrent, Charge Direction (COC)
SS
DD
SS
CE
) exceed V
) drops below the undervoltage threshold,
. The FETs remain off until (V
2
- V
9
MSB - ADDRESS 1Ch, V
MSB - ADDRESS 0Ch, V
TP
). The DS2775–DS2778 provide a test
SS
SS
2
PPD
8
OCD
. If V
. If V
UV
from PLS to V
.
RC
, the DS2775–DS2778 shut off
COC
DOC
2
SNS
SNS
7
) from PLS to V
, for a period longer than
, for a period longer than
is less than the charge
exceeds the discharge
2
IN2
Undervoltage (UV)
6
- V
IN2
IN1
2
IN1
- V
- V
5
SS
IN2
IN2
IN1
SS
, pulling PLS
) and (V
DD
2
- V
- V
4
DD
to gently
IN1
IN1
- V
PLS
LSb
) and
IN1
2
UVD
) or
SNS
SNS
3
TP
>
).
-
,
The DS2775–DS2778 provide a test current of value
I
the removal of the offending low-impedance load.
If V
period longer than short-circuit delay, t
DS2775–DS2778 shut off the external discharge FET.
The discharge current path is not reestablished until
the voltage on PLS rises above (V
DS2775–DS2778 provide a test current of value I
from V
removal of the short circuit.
All the protection conditions described are logic
ANDed to affect the CC and DC outputs.
Cell voltages are measured every 440ms. The lowest
potential cell, V
The highest potential cell, V
respect to V
range of -5V to +4.9951V and a resolution of 4.8828mV
and placed in the Result register in two’s complement
form. Voltages above the maximum register value are
reported as 7FE0h.
(overcurrent, charge direction) AND (Protection register
DC = (undervoltage) AND (overcurrent, either direction)
TST
MSb
UNITS: 4.883mV
2
SNS
2
from V
AND (short circuit) AND (Protection register bit
CC = (overvoltage) AND (undervoltage) AND
DD
exceeds short-circuit threshold, V
2
to PLS, pulling PLS up, in order to detect the
1
DD
LSB - ADDRESS 1Dh, V
LSB - ADDRESS 0Dh, V
IN1
to PLS, pulling PLS up, in order to detect
. Battery voltages are measured with a
IN1
2
0
Voltage Measurements
, is measured with respect to V
bit CE = 0)
X
DE = 0)
X
IN2
Short Circuit (SC)
IN2
IN1
, is measured with
X
- V
- V
IN1
SS
DD
X
- V
SCD
SC
TP
LSb
X
, for a
). The
, the
TST
SS
.