MITSUMI MM1293

MITSUMI
Protection of Lithium Ion Batteries (three cells in series) MM1293
Protection of Lithium Ion Batteries (three cells in series)
Monolithic IC MM1293
Outline
This IC provides protection for lithium ion batteries in the event of overcharging, overdischarging and
overcurrents. When anomalies occur during charging or at other times and excessive voltages are applied,
after a certain time has elapsed for each cell an external FET switch is turned off (overcharging detection) ;
and in order to prevent overdischarge of the battery during discharge, when the voltage of individual batteries
falls below a fixed voltage, an external FET switch is turned off (overdischarging detection), and the IC is put
into low-consumption current mode. When large currents flow due to a short-circuit or other cause, an
external MOS switch is turned off (overcurrent detection).
3-Cell Protection ICs
Rank
A
B
C
D
E
F
G
Overcharge Overcharge Overdischarge Overdischarge Overcurrent At overcurrent Overcurrent release
detection voltage hysteresis voltage detection voltage resume voltage detection voltage
detection
conditions
Load release
4.35V±50mV 200mV typ. 2.35V typ. 3.05V typ.
150mV typ. Pin 3 (DOHG pin) L H
250kΩ or more
4.25V±50mV
2.40V typ. 3.10V typ.
Same as rank A
Same as rank A
Pin 4 (OL pin) H L
Same as rank B
Same as rank B
none (several mV)
Same as rank B
Pin 3 (DOHG pin) L H
4.10V±50mV
2.35V typ. 3.00V typ.
Same as rank A 200mV typ.
Same as rank A
Charging reset
Features
1. Current consumption (overcharging)
VCELL > VCELLU
125µA typ.
2. Current consumption (normal operation)
VCELL < VALM
30µA typ.
3. Current consumption (overdischarge)
VCELL < VCELLS
0.1µA max.
4. Overcharge detection voltage (-20 to +70°C) VCELL : L H
4.25V±50mV/CELL
5. Overcharge hystereis voltage
VCELL : H L
VCELLU-200mV/CELL typ.
6. Overcharge sensing dead time
C=0.1µF
1.0S typ.
7. Overcharge sensing operation voltage
VCELL : L H
4.10V±150mV/CELL
8. Overdischarge detection voltage
VCELL : H L
2.40V/CELL typ.
9. Overdischarge sensing dead time
C=0.1µF
1.0S typ.
10.Overcurrent detection voltage
0.15V typ.
11.Overcharge and overdischarve voltages as well as the overcurrent detection voltage can be changed upon
request.
Package
SSOP-16
Applications
Lithium ion battery pack for notebook computers
Protection of Lithium Ion Batteries (three cells in series) MM1293
MITSUMI
Block Diagram
Pin Assignment
16 15 14 13 12 11 10 9
1 2 3 4 5 6 7 8
SSOP-16
1
OV
9
GND
2
CS
10
ML
3
DCHG
11
BATL
4
PF
12
MM
5
CDC
13
BATM
6
COL
14
MH
7
COV
15
BATH
8
MSW
16
VCC
Protection of Lithium Ion Batteries (three cells in series) MM1293
MITSUMI
Pin Assignment
Pin no.
Pin name Input/output
Function
Overcharge detection output pin
NPN transistor open collector output; normally high impedance, goes to L
level on overdischarge
Overcurrent detection pin
Monitors equivalent load current through source-drain voltage drop of discharge-controlling
FET, and at or above the overcurrent detection voltage sets the DCHG pin to "H" and turns
off the discharge-controlling FET. Following overcurrent detection, current is passed from
this pin, and if the load is decreased, the overcurrent mode is canceled. Through this action
there is a temporary consumption current (at the VCC pin) of approx. 1 mA on resumption of
discharge and detection of overdischarge. This function is disabled in overdischarge mode.
Pin driving the discharge-controlling FET (P-ch)
Normally "L"; on overdischarge set to "H"
Output pin for overdischarge detection signals
Overdischarge detection pin
When the overdischarge detector detects overdischarge at the open collector output of
the NPN transistor, this pin is turned on. A delay is provided by setting a dead time until
discharge ends, so that by utilizing a reset or other signal from a CPU or some other
controlling device, the equipment can be put into standby mode.
Pin to set the dead time for overdischarge detection
By connecting a capacitor between the CDC pin and GND, a dead time can be set.
Pin to set the dead time for overcurrent detection
Pin to set the dead time for overcurrent detection
By connecting a capacitor between the COL pin and GND, a dead time can be
set. If NC, protection is triggered in a short amount of time; the dead time
should be set according to the application.
Pin to set the dead time for overcharge detection
By connecting a capacitor between the COV pin and GND, a dead time can be
set.
Pin to switch the cell voltage monitor on/off
GND: monitor on, VCC: monitor off
The cell voltage monitor converts the different cell voltages to a GNDreference voltage and outputs it from the ML, MM and MH pins.
1
OV
Output
2
CS
Input
3
DCHG
Output
4
PF
Output
5
CDC
Input
6
COL
Input
7
COV
Input
8
MSW
Input
9
GND
Input
10
ML
Output
11
BATL
Input
12
MM
Output
13
BATM
Input
14
MH
Output
15
BATH
Input
Pin for input of H cell high-side voltage
16
VCC
Input
Power supply input pin
The same potential as the BATH pin should be input
Absolute Maximun Ratings
Ground pin
Monitor output pin for the L cell voltage
Pin for input of L cell high-side voltage and M cell low-side voltage
Monitor output pin for the M cell voltage
Pin for input of M cell high-side voltage and H cell low-side voltage
Monitor output pin for the H cell voltage
(Ta=25°C)
Item
Symbol
Ratings
Units
Storage temperature
TSTG
-40~+125
°C
Operating temperature
TOPR
-20~+70
°C
Charge voltage
VBAT max.
18
V
Power supply voltage
VCC max.
18
V
Voltage applied to OV pin
VOV max.
18
V
Allowable loss
Pd
300
mW
Protection of Lithium Ion Batteries (three cells in series) MM1293
MITSUMI
Recommended Operating Conditions
Item
Symbol
Ratings
Units
Operating temperature
TOPR
-20~+70
°C
Operating voltage
VOPR
+2~+18
V
Electrical Characteristics
(Except where noted otherwise, Ta=25°C, VCC=15V, VCELL=VBATH=VBATM=VBATL)
Item
Symbol
Measurement conditions
Consumption current (VCC pin) 1
ICC1
VCELL=4.4V
125
250
µA
Consumption current (VCC pin) 2
ICC2
VCELL=3.5V
30
60
µA
Consumption current (VCC pin) 3
ICC3
VCELL=2.2V
0.1
µA
Consumption current (BATH pin) 1
IBATH1
VCELL=4.4V
11
22
µA
Consumption current (BATH pin) 2
IBATH2
VCELL=3.5V
5
10
µA
Consumption current (BATH pin) 3
IBATH3
VCELL=2.2V
2
4
µA
BATM pin input current 1
IBATM
VCELL=3.5V
±300
nA
BATM pin input current 2
IBATMA
VCELL=4.4V
0
µA
BATL pin input current 1
IBATL
VCELL=3.5V
±300
nA
BATL pin input current 2
IBATLA
VCELL=4.4V
Overcharge detection voltage
VCELLU
Ta=-20~+70°C, VCELL : 3.7V
VCELLO
VCELL : 4.5V
Overcharge detection
release voltage
Overcharge sensing dead time
tOV
Overcharge sensing operation voltage
VALM
Min. Typ. Max. Units
-0.6
4.5V
3.7V
COV=0.1µF
-0.3
-0.6
-0.3
0
µA
4.20
4.25
4.30
V
VCELLU VCELLU VCELLU
-260mV -200mV -140mV
V
0.5
1.0
1.5
S
VCELL : 3.5V
4.4V
3.95
4.10
4.25
V
Overdischarge sensing hysteresis voltage
VALM
VCELL : 4.4V
3.5V
120
200
300
mV
Overdischarge detection voltage
VCELLS
VCELL : 3.5V
2.0V
2.30
2.40
2.50
V
Discharge resume voltage
VCELLD
VCELL : 2.0V
3.5V
2.95
3.10
3.25
V
VCELLD-VCELLS
490
700
910
mV
0.5
1.0
1.5
S
Overdischarge sensing hysteresis voltage
VCSD
Overdischarge sensing dead time
tCDC1
CCDC=0.1µF
Overdischarge reset dead time
tCDC2
CCDC=0.1µF, VCS=VCC+0.3V
7
mS
Overcurrent detection voltage
VOC
VCC-VCS, DCHG
0.135 0.150 0.165
V
Overcurrent sensing dead time
tCOL1
CCOL=0.001µF, DCHG
5
10
15
mS
Overcurrent reset dead time
tCOL2
CCOL=0.001µF, DCHG
5
10
15
mS
Overcurrent sensing delay time
tCOL3
CCOL=0, DCHG
150
µS
Overcurrent reset delay time
tCOL4
CCOL=0, DCHG
150
µS
Open-load condition 250kΩ
Overcurrent protection release
DCHG pin source current
ISODCH
VCELL < VCELLS, SW1 : A, VDCHG=VCC -1.8V
20
µA
DCHG pin sync current
ISIDCH
VCELL > VCELLS, SW1 : A, VDCHG=0.8V
20
µA
DCHG pin output voltage H
VTHDCH
VCC -VDCHG, ISO=20µA, SW1 : B
1.8
V
DCHG pin output voltage L
VTHDCL
VDCHG -GND, ISI=-20µA, SW1 : B
0.8
V
OV pin sync current
ISIOV
VOV=0.4V, Ta=-20~+70°C
0.2
mA
PF pin sync current
ISIPF
VPF=0.4V, Ta=-20~+70°C
10
µA
Protection of Lithium Ion Batteries (three cells in series) MM1293
MITSUMI
Timing Chart
Overcharge
Charging off
Overcharge detection voltage
Overcharge detection cancel voltage
Cell voltage
COV pin
tOV
Sensing dead zone
Pin OV
(pulled up)
Overcharge state
Normal state
Overdischarge
Discharge off
Discharge resume voltage
Cell voltage
Overdischarge detection voltage
CDC pin
tCDC1
Sensing dead zone
tCDC2
Reset dead zone
DCHG pin
Overdischarge state
Normal state
Pin PF
(pulled up)
Overcurrent
Current passed
from pin CS
Load released
CS pin
COL pin
tCOL
Sensing dead zone
tCOL
Reset dead zone
DCHG pin
Normal state
Overcurrent state
Normal state
Protection of Lithium Ion Batteries (three cells in series) MM1293
MITSUMI
Application circuits
Characteristics
Overcharge, overdischarge sensing dead time
Overcurrent dead time
100m
Dead time t (s)
Dead time t (s)
1
100m
10m
1m
100P
1000P
0.01µ
Capacitance C (F)
0.1µ
10m
1m
10P
100P
0.001µ
0.01µ
Capacitance C (F)
Note : The above characteristics are representative and are not guaranteed.