SILAN SC121NGTR

SC121
LI+ BATTERY PROTECTION CIRCUIT
DESCRIPTION
SC121 is a LI+ battery protection circuit. It is suitable for protecting LI+
battery against damage from over charge, over discharge, and over
current. It contains high accurate voltage detection and delay circuits.
FEATURES
* Low supply current
* Over-charge detect 4.28V, Over-charge release 4.10V.
* Over-discharge detect 2.50V, Over-discharge release 2.90V.
* Over-current detect 0.15V, Short Current detect 1.00V.
* Overcharge/over-discharge/over-current detection delay
* Charger detection
* Reset resistance for over current protection
APPLICATIONS
* Wide supply voltage range
* Small package
* Protection IC for One-Cell LI+
Battery Pack
ORDERING INFORMATION
Part No.
Package
SC121NTR
SC121NATR
SC121NGTR
SC121NAGTR
Marking
121N
SOT-23-6
Pb free
Package Type
Tape & Reel
121NA
Pb free
Tape & Reel
121NG
Halogen free
Tape & Reel
121NAG
Halogen free
Tape & Reel
HANGZHOU MICROELECTRONICS CO.,LTD
Http:// www.silan.com.cn
Material
REV:1.6
2009.07.20
Page 1 of 9
SC121
BLOCK DIAGRAM
ABSOLUTE MAXIMUM RATING
Characteristics
Symbol
Value
Unit
Supply Voltage
VDD
VSS-0.3 ~ VSS+12
V
OC Output Pin Voltage
VOC
VDD-15 ~ VDD+0.3
V
OD Output Pin Voltage
VOD
VSS-0.3 ~ VDD+0.3
V
CSI Input Pin Voltage
VCSI
VDD-15 ~ VDD+0.3
V
Operating Temperature Range
TOPR
-40 ~ + 85
°C
Storage Temperature Range
TSTG
-40 ~ +125
°C
ELECTRICAL CHARACTERISTICS (Tamb=25°C, unless otherwise specified)
Characteristics
Symbol
Status
Min.
Typ.
Max.
Unit
8.0
V
Operating Voltage
Operating Voltage
VDD
1.8
Current Consumption
Supply Current
IDD
VDD=3.9V
3.0
6.0
µA
Power Down Current
IPD
VDD=2.0V
0.3
0.6
µA
Detection Voltage
Over Charge Detection Voltage
VOCU
4.24
4.28
4.32
V
Over Charge Release Voltage
VOCR
4.05
4.10
4.15
V
Over Discharge Detection Voltage
VODL
2.40
2.50
2.60
V
Over Discharge Release Voltage
VODR
2.80
2.90
3.00
V
HANGZHOU MICROELECTRONICS CO.,LTD
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REV:1.6
2009.07.20
Page 2 of 9
SC121
Characteristics
Symbol
Over Current 1 Detection Voltage
Status
VOI1
Over Current 2(Short Current)Detection
Min.
Typ.
Max.
Unit
0.13
0.15
0.17
V
VOI2
VDD=3.6V
0.80
1.00
1.20
V
Over Current Reset Resistor
Rshort
VDD=3.6V
400
500
600
kΩ
Charger Detection Voltage
VCH
-0.8
-0.5
-0.2
V
Voltage
Delay Time
Over Charge Detection Delay Time
TOC
VDD=3.6V~4.4V
150
340
500
ms
Over Discharge Detection Delay Time
TOD
VDD=3.6V~2.0V
80
200
300
ms
Over Current 1 Detection Delay Time
TOI1
VDD=3.6V
5
13
20
ms
TOI2
VDD=3.6V
5
50
µs
Over Current 2(Short Current)Detection
Delay Time
Other
OC Pin Output “H”Voltage
Voh1
OC Pin Output “L”Voltage
Vol1
OD Pin Output “H”Voltage
Voh2
OD Pin Output “L”Voltage
Vol2
0 V battery charge starting charger
voltage
VOCHA
VDD-0.1 VDD-0.02
0.01
V
0.1
VDD-0.1 VDD-0.02
0.01
SC121NA
V
V
0.1
1.55
V
V
PIN CONFIGURATION
PIN DESCRIPTIONS
PIN No.
Symbol
I/O
Description
1
OD
O
FET gate connection pin for discharge control.
2
CSI
I/O
Input pin for current sense, charger detect.
3
OC
O
FET gate connection pin for charge control.
4
TD
I
Test pin for reduce delay time.
5
VDD
I
Positive power input pin.
6
VSS
I
Negative power input pin.
HANGZHOU MICROELECTRONICS CO.,LTD
Http:// www.silan.com.cn
REV:1.6
2009.07.20
Page 3 of 9
SC121
FUNCTION DESCRIPTIONS
Normal Status
If VODL<VDD<VOCU and VCH<VCSI<VOI1, M1 and M2 are both turned on (refer to Typical Application Circuits).
The charging and discharging processes can be operated normally.
Overcharge Detection
When enter charging from normal status, the battery voltage can be detected from VDD. When the battery is in
overcharge status, VDD is larger than VOCU over a delay time of TOC, M2 is to be turned off.
Release of Overcharge Status
There are two ways to return to normal status from overcharge status.
• If the battery is self discharging and VDD<VOCR occurs, M2 is to be turned on and back to normal status.
• Remove the charger and connected to a load. If VOCR<VDD<VOCU and VCSI>VOI1 occurs, M2 is to be turned
on and back to normal status.
Over discharge Detection
When enter discharging from normal status, the battery voltage can be detected from V DD. When the battery is
in over discharge status, VDD is smaller than VODL over a delay time of TOD; M1 is to be turned off. In the
meanwhile, CSI is pulled to VDD by way of internal resistor RCSID. If VCSI>VOI2, the protection IC enters into
Power-down mode. (Its current consumption is lower than 0.3µA).
Release of Power-down mode
A charger is connected while the battery remains in Power-down mode. If VCH<VCSI<VOI2 and VDD<VODR
occur, M1 is still off but it releases Power-down mode. If VDD>VODR occurs, M1 is to be turned on and back to
normal status.
Charger Detection
If a charger is connected to the battery remained in Power-down mode, the voltages will become VCSI<VCH
and VDD>VODL. M1 is to be turned on and back to normal status.
Abnormal Charging Status
If a charger is connected to the battery in normal status, VCSI<VCH occurs over a delay time longer than TOC,
M2 is to be turned off.
Over Current/Short Current Detection
When the discharging current is too large during discharging under normal status and the voltage detected
from CSI is larger than VOIX (VIO1 or VIO2) for over a certain delay time TOIX (TIO1 or TIO2), it means the over
current/short current status occurred. M1 is turned off. CSI is pulled to VSS by way of an internal resistor RCSIS.
Release of Over Current/Short Current Status
While the protection IC remains in Over Current/Short Current status and load is removed or the impedance
between VBAT+ and VBAT- is larger than 500KΩ and VCSI<VOI1, M1 is to be turned on and back to normal status.
Note: when a battery is connected to a protection IC for the first time, the IC may not enter the normal status (not
dischargeable status). If this occurs, set the CSI pin voltage equal to the VSS voltage (short the CSI and
VSS pins or connect a charger) to enter the normal status.
HANGZHOU MICROELECTRONICS CO.,LTD
Http:// www.silan.com.cn
REV:1.6
2009.07.20
Page 4 of 9
SC121
TIMING DIAGRAM
Overcharge Status →Self Discharging →Normal Status
Charger load
VOCU
VOCR
VODR
VODL
VDD
CSI
VDD
VSS
VDD
VSS
VCH
Self discharging
TOC
Overcharge Status→Load Discharging→Normal Status
HANGZHOU MICROELECTRONICS CO.,LTD
Http:// www.silan.com.cn
REV:1.6
2009.07.20
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SC121
Overcharge Status→Charging By Charger→Normal Status
Overcharge Status→Abnormal Status→Normal Status
Charger load
Battery voltage
VOCU
VOCR
VODR
CSI pin
OD pin
OC pin
VODL
VDD
CSI
VDD
VSS
VDD
VOI2
VSS
VCH
TOD
TOC
HANGZHOU MICROELECTRONICS CO.,LTD
Http:// www.silan.com.cn
REV:1.6
2009.07.20
Page 6 of 9
SC121
Over Current Status→Normal Status
STATE DIAGRAM OF OPERATION
HANGZHOU MICROELECTRONICS CO.,LTD
Http:// www.silan.com.cn
REV:1.6
2009.07.20
Page 7 of 9
SC121
TYPICAL APPLICATION CIRCUITS
Note: The circuit and parameters are reference only, please set the parameters of the real application
circuit based on the real test.
HANGZHOU MICROELECTRONICS CO.,LTD
Http:// www.silan.com.cn
REV:1.6
2009.07.20
Page 8 of 9
SC121
PACKAGE OUTLINE
SOT-23-6
UNIT: mm
HANDLING MOS DEVICES:
Electrostatic charges can exist in many things. All of our MOS devices are internally protected against
electrostatic discharge but they can be damaged if the following precautions are not taken:
• Persons at a work bench should be earthed via a wrist strap.
• Equipment cases should be earthed.
• All tools used during assembly, including soldering tools and solder baths, must be earthed.
• MOS devices should be packed for dispatch in antistatic/conductive containers.
Disclaimer:
•
Silan reserves the right to make changes to the information herein for the improvement of the design and performance
without further notice!
•
All semiconductor products malfunction or fail with some probability under special conditions. When using Silan products
in system design or complete machine manufacturing, it is the responsibility of the buyer to comply with the safety
standards strictly and take essential measures to avoid situations in which a malfunction or failure of such Silan products
could cause loss of body injury or damage to property.
•
Silan will supply the best possible product for customers!
HANGZHOU MICROELECTRONICS CO.,LTD
Http:// www.silan.com.cn
REV:1.6
2009.07.20
Page 9 of 9