Datasheet SC451 Datasheet (SILAN)

Silan
Semiconductors





LI-ION BATTERY PROTECTOR

DESCRIPTION

The SC451XX series are protection ICs for over-charge
/discharge of rechargeable one-cell Lithium-ion (Li+) batteries
by CMOS process.

The SC451XX series can detect over-charge/discharge
of Li+ one-cell and excess load current, further include a
short circuit protector for preventing large external short
circuit current.

FEATURES

* Low supply current.

* High withstand voltage.
* High accuracy detector threshold.
* Variety of detector threshold.
* Built-in protection circuit.
* Output delay of over-charge.

* Ultra small package: SOT-26

SC451XX

SOT-26

APPLICATIONS

* Over-charge/over-discharge protection for Li+

one-cell pack

* High precision protectors for cell-phones and any

other gadgets using on board Li+ one-cell
battery.



PIN ASSIGNMENT BLOCK DIAGRAM

V

DD Ct

5 2

5

6

1

SC451XX

2

4

VD1

VD2

3

3 4 1 6

SS DOUT COUT V-

V

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

1

VD3

Level

shift

delay

short circuit

detector

Rev: 1.0 2000.12.31





Silan
Semiconductors





ABSOLUTE MAXIMUM RATING

Characteristic Symbol Value Unit

Supply Voltage V

Input Voltage

Output Voltage

PowerDissipation P
Storage Temperature T
Operating Temperature T

V
V

DD

V- VDD-18~VDD+0.3 V

V

CT
COUT
DOUT

D
STG
OPR

0.3 ~ 12 V

Vss-0.3~VDD+0.3 V

VDD-18~VDD+0.3 V

Vss-0.3~VDD+0.3 V

150 mW

-55 ~ +125

-40~+85

ELECTRICAL CHARACTERISTICS

Sc451XX-01

Operating Voltage V
Min Operating Voltage for 0V
Charging

Over-charge Threshold Voltage V

Over-charge Threshold Hysteresis
Range
Output Delay Time of Over-charge T

Over-discharge Threshold Voltage V

Output Delay Time of Over-Discharge T

Excess Current Threshold Voltage V

Output Delay Time of Excess Current T
Short Detection Voltage Vshort VDD=3.0V VDD-1.1 VDD-0.8 VDD-0.5 V
Output Delay Time of Short Detection Tshort VDD=3.0V 5 50
Reset Resistance for Excess Current
Protection
Nch ON Voltage of COUT V
Pch ON Voltage of COUT V
Nch ON Voltage of DOUT V
Pch ON voltage of DOUT V
Supply Current I
Standby Current Istandby VDD=2.0V 0.3 0.6



Parameter Symbol Conditions Min Typ Max Unit

V

Rshort V

(Tamb=25°C, unless otherwise specified)

Voltage defined as VDD-V

DD1

Voltage defined as VDD-V-,

V

st

V

=0V

DD-VSS

Detect rising edge of supply

DET1

voltage

HYS1

C3=0.01µF,VDD=3.6V→4.3V

VDET1

Detect falling edge of supply

DET2

voltage
VDD=3.6V→2.4V

VDET2

Detect rising edge of “V-” pin

DET3

voltage

VDET3VDD

OL1
OH1
OL2
OH2
DDVDD

=3.0V 9 13 17 ms

=3.6V, V- =1.0 50 100 150

DD

IOL=50µA,VDD=4.4V
IOH=-50µA,VDD=3.9V
IOL=50µA,VDD=2.4V
IOH=-50µA,VDD=3.9V

=3.9V,V- =0V 3.0 6.0

SS

SC451XX

°C
°C

1.5 10 V

1.2 V

4.20 4.25 4.30 V

0.15 0.2 0.25 V

50 75 100 ms

2.437 2.500 2.563 V

71013ms

0.17 0.20 0.23 V

0.2 0.5 V

3.4 3.8 V

0.2 0.5 V

3.4 3.7 V

µs

kΩ

µA
µA

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

2





Silan
Semiconductors





SC451XX-02

Parameter Symbol Conditions Min Typ Max Unit

Operating Voltage V
Min Operating Voltage for 0V
Charging

Over-charge Threshold Voltage V

Over-charge Threshold Hysteresis
Range
Output Delay Time of Over-charge T

Over-discharge Threshold Voltage V

Output Delay Time of Over-discharge T

Excess Current Threshold Voltage V

Output Delay Time of Excess Current T
Short Detection Voltage Vshort VDD=3.0V VDD-1.1 VDD-0.8 VDD-0.5 V
Output Delay Time of Short Detection Tshort VDD=3.0V 5 50 µs
Reset Resistance for Excess Current
Protection
Nch ON Voltage of C
Pch ON Voltage of C
Nch ON Voltage of D
Pch ON Voltage of D
Supply Current I
Standby Current Istandby VDD=2.0V 0.3 0.6 µA

OUT
OUT
OUT
OUT

V

Rshort V

Voltage defined as VDD-V

DD1

Voltage defined as VDD-V-,

V

st

V

=0V

DD-VSS

Detect rising edge of supply

DET1

voltage

HYS1

C3=0.01µF,VDD=3.6V→4.3V 55 80 105 ms

VDET1

Detect falling edge of supply

DET2

voltage
VDD=3.6V→2.4V 7 10 13 ms

VDET2

Detect rising edge of “V-” pin

DET3

voltage

VDET3VDD

V

OL1

V

OH1IOH

V

OL2IOL

V

OH2IOH
DD

=3.0V 9 13 17 ms

=3.6V, V- =1.0 50 100 150 kΩ

DD

IOL=50µA, VDD=4.4V 0.2 0.5 V

=-50µA, VDD=3.9V 3.4 3.8 V

=50µA, VDD=2.4V 0.2 0.5 V

=-50µA, VDD=3.9V 3.4 3.7 V

VDD=3.9V, V- =0V 3.0 6.0 µA

SS

PIN DESCRIPTION

PIN No. Symbol Description

1C
2CTPin for external capacitor setting output delay of VD1
3VSSGround
4D
5VDDPower supply
6 V- Pin for charger negative input

OUT

OUT

Output of over-charge detection, CMOS output

Output of over-discharge detection, CMOS output

SC451XX

1.5 10 V

1.2 V

4.30 4.35 4.40 V

0.15 0.2 0.25 V

2.437 2.500 2.563 V

0.17 0.20 0.23 V

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

3





Silan
Semiconductors





FUNCTIONAL DESCRIPTION

•

VD1/OVER-CHARGE DETECTOR

The VD1 monitors V
fromalowvaluetoavaluehigherthantheV
control Nch-MOS-FET turns to “off” with C

An output delay time for over-charges detection can be set by an external capacitor C3 connecting the V
pin and Ct pin. The external capacitor can make a delay time form a moment detecting over-charge to a time
output a signal which enables charge control Nch-MOS-FET for turning to “off”. Though the V
going up to a higher level than V
signal for turning “off” of charge control Nch-MOS-FET. The output delay time can be calculated as below:

VDET1

=

t

A level shifter incorporated in a buffer driver for the C
and the “H” of C

•

RESET CONDITIONS FROM OVERCHARGING OF SC451XX-01

OUT

There can be two cases to reset the VD1 making the C

Resetting the V

makes the charging system ready for resumption of charging process.

D1

The first case is in such condition that a time when the V

“V

DET1-VHYS1

”. While in the second case, disconnecting a charger from the battery pack can make the VD1

resetting when the V

After detecting over-charge with the V
battery pack makes load current allowable through parasitic diode of external charge control Nch-MOS-FET. The
C

level would be “H” when the VDDlevel is coming down to a level below the V

OUT

load current.

•

RESET CONDITIONS FROM OVERCHARGING OF SC451XX-02

After detecting over-charge, the V
the exception that a cell voltage reaches to a lower value than “V
After detecting over-charge, when the V
pack to a system load makes battery pack being disable at for charging or discharging because of excess current
detector operated being D

pin voltage. When the VDDvoltage crosses over-charge detector threshold V

DD

, the VD1 can sense over-charging and an external charge

DET1

pin being at “L”.

OUT

if it is within a time period of the output delay time, VD1 would not output a

DET1

DD

0.7)(VC3

−×

6

−

100.48

×

pin makes the “L” of C

OUT

pin is set to VDDvoltage with CMOS buffer.

pin level to “H” again after detecting over-charge.

OUT

voltage is coming down to a level lower than

DD

level is within hysteresis width (V

DD

OUT

”L”.

DD

would not be release and C

D1

level stays at a value higher than “V

DD

DET1-VHYS1≤VDD≤VDET1

voltage of higher than V

OUT

DET1-VHYS1

DET1

level would not switch to “H” again with

SC451XX

voltage would be

DD

pin to the V-pin voltage

OUT

).

, connecting system load to the

by continuous drawing of

DET1

” by self discharge of cell or else.

DET1-VHYS1

”, to connect battery

DET1

SS

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

4





Silan
Semiconductors





•

VD2/OVER-DISCHARGE DETECTOR

The V

V

DET2

external discharge control Nch-MOS-FET turns to “off” with the D

Resetting the V
connecting a charger to the battery pack. When the V
V

DET2

V

voltage comes up to a value larger than V

DD

discharge control Nch-MOS-FET. Connecting a charger to the battery pack makes the D
instantaneously when the V

When a cell voltage equals to zero, connecting charger to the battery pack makes the system allowable for
charge with higher charge voltage than Vst, 1.2V Max.

An output delay time of the over-discharge detection is fixed internally. Though the V
going down to a lower level than V
a signal for turning “off” of discharge control Nch-MOS-FET.

After detection of an over-discharge by V
and into standby, only the charger detector is operating.

The output type of D

monitors a VDDpin voltage. When the VDDvoltage crosses the over-discharge detector threshold

D2

from a high value to a value lower than the V

with the D

D2

pin level being “H” again after detecting over-discharge is only possible by

OUT

,theVD2can sense an over-discharging and the

DET2

pin being at “L”.

OUT

voltage stays under over-discharge detector threshold

DD

charge current can flow through parasitic diode of external discharge control Nch-MOS-FET, then after the

discharging process would be advanced through “on” state

DET2

voltage is higher than V

DD

if it is within a time period of the output delay time, VD2would not output

DET2

, supply current would be reduced to 0.3µATYP. at VDD=2.0V

D2

pin is CMOS having “H” level of VDDand “L” level of VSS.

OUT

DET2

.

SC451XX

OUT

DD

level being “H”

voltage would be

•

VD3/EXCESS CURRENT DETECTOR, SHORT CIRCUIT PROTECTOR

*Both of the excess current detector and short circuit protector can work when both control Nch-MOS-FETs
are in “on” state.

When the V-pin voltage is going up to a value between the short protection voltage Vshort and excess
current threshold V

, the excess current detector operates and further soaring of V-pin voltage higher than

DET3

Vshort makes the short circuit protector enabled. As a result the external discharge control Nch-MOS-FET turns
to “off” with the D

*An output delay time for the excess current detector is internally fixed, 13ms TYP. at V

recovery of V-pin level from a value between Vshort and V

pin being at “L”.

OUT

=3.0V. A quick

DD

within the delay time keeps the discharge control

DET3

FET staying “ON” state.

When the short circuit protector is enabled, the D

*The V-pin has a built-in pull down resistor, TYP.100KΩ, connected to the V

would be “L” and its delay time would be 5µs TYP.

OUT

pin.

SS

After an excess current or short circuit protection is detected, removing a cause of excess current or external
short circuit makes an external discharge control Nch-MOS-FET to an “on” state automatically with the V-pin level
being down to the V

*WhenV

DD

enter a standby mode, while V

level through the built-in pull down resistor.

SS

voltage is higher than V

voltage is lower than V

DD

at a time when the excess current is detected the SC451XX does not

DET2

the SC451XX enters a standby mode.

DET2

After detecting short circuit the SC451XX will not enter a standby mode.

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

5





Silan
Semiconductors



TIMING DIAGRAM

Charging discharging Charging discharging Charging discharging

V

DET1

V

DET1-VHYS1

VDD

V

DET2

VDD

Vshort

V-

DET3

V

VSS



SC451XX

excess

short

current

Charging

open

current

open

t

Charging/

discharging

COUT

DOUT

charging

current

current

discharging

current

VDD

VDD

VSS

t

VDET1

V-

0

t

VDET1

t

VDET2

t

VDET2

t

VDET3tshort

t

t

t

t

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

6





Silan
Semiconductors



TEST CIRCUITS

DD

V

V-

v

V

SS

V

DD



V

DD

5

Ct

2

6

C

OUT

1

3

5

5

V-

6

V

SS

3

V

DD

5

SC451XX

D

OUT

4v

V-

6

A

v

V

SS

3

V

DD

5

V-

6

V

SS

3

1

D

OUT

4

OUT

50A

C

v

V-

6

V

SS

3

V

DD

5

V-

6

V

SS

3

C

1

4

OUT

D

v

OUT

50A

50A

v

(To be continued)

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

7







(Continued)

Silan
Semiconductors



SC451XX

V

DD

5

V-

6

V

SS

3

R

1

V

DD

C

1

5

V-

6

V

SS

3

D

OUT

4

v

C

3

Ct

2

C

OUT

1v

TYPICAL APPLICATION CIRCUITS

R1

100





C3 0.01



Ct

VSS

C1

0.1

50A

2

3

C2 0.1

DD

V

5

v

V-

6

V

SS

3

5

R

2

C

2

6

D

OUT

4v

3

+

V

DD

5

V-

6SC451XX

14

COUTDOUT



1K

R2



-

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

8





Silan

0

0

0

Semiconductors



TYPICAL PERFORMANCE CHARACTERISTICS

4.27

4.26

4.25

4.24

(V)

4.23

DET1

V

4.22

4.21

Over-charge threshold

4.20

-60 -40 -20 0 20 40 60 80 100 -60 -40 -20 0 20 40 60 80 10

Temperature Topt(



k

) Temperature Topt(k)

SC451XX

2.54

2.53

2.52

(V)

2.51

DET2

2.50

V

2.49

2.48

Over-discharge threshold

2.47

Excess current threshold

Output delay of over-charge

0.210

0.205

(V)

0.200

DET3

V

0.195

0.190

-60 -40 -20 0 20 40 60 80 100

100

90
80

(ms)

70
60

VDET1

t

50
40
30
20

-60 -40 -20 0 20 40 60 80 100

Temperature Topt(k) Temperature Topt(k)

Short circuit protector threshold

Output delay of over-discharge

2.40

2.35

2.30

2.25

2.20

Vshort(V)

2.15

2.10

-60 -40 -20 0 20 40 60 80 10

Temperature Topt(

18
16
14
12

(ms)

10

8

VDET2

t

6
4
2

-60 -40 -20 0 20 40 60 80 10

k

)Temperature Topt(k)

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

9





Silan
Semiconductors



TYPICAL PERFORMANCE CHARACTERISTICS

20
18

16
14
12
10

VDET3(ms)

8

t

6
4

Output delay of excess current

2

-60 -40 -20 0 20 40 60 80 100 -60 -40 -20 0 20 40 60 80 100

Temperature Topt(

0.210

0.205

0.200

HYS1(V)

V

0.195

0.190

Over-charge tresholdhysteresis

-60 -40 -20 0 20 40 60 80 100 -60 -40 -20 0 20 40 60 80 100



DD

=3.0V VDD=3.0V

V

k

)

(continued)

10

8

6

4

short(S)

t

2

0

Output delay of short circuit protector

4.0

3.5

3.0

DD(A)

2.5

2.0

1.5

1.0

SupplycurrentI

0.5

0.0

SC451XX

Temperature Topt(

VDD=3.9V V-=0V

Temperature Topt(k)Temperature Topt(k)

k

)

V

DD

k

=2.0V

)

0.40

0.35

0.30

0.25

0.20

0.15

0.10

0.05

Standby current Istandby(A)

0.00

-60 -40 -20 0 20 40 60 80 100

Temperature Topt(

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31





10

Silan
Semiconductors



TYPICAL PERFORMANCE CHARACTERISTICS

0.30

0.25

0.20

0.15

0.10

0.05

0.00

OUT Nch Driver ON Voltage VOL1(V)

-60 -40 -20 0 20 40 60 80 100 -60 -40 -20 0 20 40 60 80 100

C

Temperature Topt() Temperature Topt(



I

OL

=50AVDD=4.4V IOH=-50AVDD=3.9V

(continued)

3.90

3.85

3.80

3.75

3.70

3.65

3.60

OUT Pch Driver ON Voltage VOH2(V)

C

SC451XX



0.30

0.25

0.20

0.15

0.10

0.05

0.00

-60 -40 -20 0 20 40 60 80 100 -60 -40 -20 0 20 40 60 80 100

DOUT Nch Driver ON Voltage VOL2(V)

IOL=50èAVDD=2.4V

Temperature Topt()

3.90

3.85

3.80

3.75

3.70

3.65

3.60

OUT Pch Driver ON Voltage VOH2(V)

D

OH

=-50AVDD=3.9V

I

Temperature Topt(



HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

11





Silan
Semiconductors



TYPICAL PERFORMANCE CHARACTERISTICS



SC451XX

(continued)

800

700
600
500
400
300
200
100

0

0 0.05 0.1

External capacitanceC3(

25.00

20.00

15.00

10.00

5.00

0.00

2.53.03.54.04.5
Supply voltage V

4.258

4.256

4.254

VDD=3.6V~4.3V RI=1K,VDD=3.0V



F) External capacitanceC2(F)

DD

(V) External resistanceR2(K)

C

1

=0 ~ 6.8F

C3=0.22F

C3=0.1F

10000

1000

100

10

1

0.001 0.01 0.1 1

0.210

0.209

VDET3(ms) Output delay of short protection tshort(s)

0.208

0.207

0.206

0.205

0.204

0.203

0.202

Output delay of excesscurrent t

0 0.5 1.0 1.5 2.0 2.5 3.0

4.252

4.250

4.248

Over-charge thresholdVDET1(V) Output delay of excess current tVDET3(ms) Output delay of over-charge tVDET1(ms)

4.246
0 200 400 600 800 1000

ExternalresistanceR1(

C3=0.01F



)

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

12





Silan
Semiconductors





PACKAGE OUTLINE

SOT-26 UNIT: mm

2.9±0.2

1.6±0.2

2.8±0.2

0.40

0.95 0.95

1.9±0.2

1.1±0.2

1.0 ~ 1.3

SC451XX

o

0~15

MIN 0.2

0~0.1

0.15

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0 2000.12.31

13



