SA57608DD_技术文档

INTEGRATED CIRCUITS

SA57608

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

Product data

2003 Oct 29

Supersedes data of 2001 Oct 03

Philips

Semiconductors

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

GENERAL DESCRIPTION

The SA57608 is a single-cell Li-ion protection IC, and is an improved

version of the NE57600, with different pinout. Its over and under

voltage accuracies are trimmed to within ± 25 mV (5%) over the

entire battery pack operating temperature range. The SA57608 is

available in various over and undervoltage limits.

There is a discharge overcurrent protection circuit which can protect

the battery pack against an accidental short-circuit. The overcharge

trip point has a time delay which can be programmed externally. It is

packaged in a space-saving 6-lead small outline package and

requires two external N-channel MOSFETs and a minimum of

passive parts.

FEATURES

APPLICATIONS

• Trimmed overvoltage trip point to within ±25 mV

• Cellular phones

• Programmable overvoltage trip time delay

• Trimmed undervoltage trip point to within ±25 mV

• Very Low undervoltage quiescent sleep current 0.05 mA

• Discharge overcurrent cutoff

• Personal digital assistants

• Palmtop computers

• Low operating current (10 mA)

• 6-lead small outline package (SOP004)

SIMPLIFIED SYSTEM DIAGRAM

V+

100 Ω

V

CC

5

0.01 µF

0.1 µF

VM

2

C

DLY

4

6

SA57608

Li-ION CELL

GND

3

1

DF

CF

1 kΩ

0.1 µF

V–

DISCHARGE

FET

CHARGE

FET

SL01568

Figure 1. Simplified system diagram.

2

2003 Oct 29

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

ORDERING INFORMATION

PACKAGE

TYPE NUMBER

TEMPERATURE

RANGE

DESCRIPTION

VERSION

SA57608XD

Plastic small outline package; 6 leads; body width 1.8 mm

SOP004

–20 to +85 °C

NOTE:

The device has six protection parameter options, indicated by the X on the order code, and defined in the following table.

TYPICAL PROTECTION PARAMETERS

Overcharge

detection voltage (V)

Overcharge detection

hysteresis voltage (mV)

Over-discharge

detection voltage (V)

Overcurrent

detection voltage (mV)

Part Number

SA57608Y

SA57608B

SA57608C

SA57608D

SA57608E

SA57608G

4.350 ±0.050

4.280 ±0.025

4.295 ±0.025

4.350 ±0.050

4.275 ±0.025

4.280 ±0.025

180

150

180

200

2.30 ±0.070

2.30 ±0.058

2.30 ±0.070

2.30 ±0.058

150 ±30

75 ±30

200 ±30

100 ±30

Part number marking

PIN CONFIGURATION

Each device is marked with a four letter code. The first three letters

designate the product. The fourth letter, represented by ‘x’, is a date

tracking code.

DF

VM

CF

GND

6

5

1

2

V

CC

Part number

SA57608YD

SA57608BD

SA57608CD

SA57608DD

SA57608ED

SA57608GD

Marking

A G X x

A G Y x

A G Z x

A H A x

A H B x

A H D x

C

DLY

4

3

SL01569

Figure 2. Pin configuration.

PIN DESCRIPTION

1

SYMBOL DESCRIPTION

DF

VM

CF

Discharge detection pin. This drives the gate of the discharge N-ch FET.

Monitor pin. Detects overcurrent and the presence of a charger.

Charge FET pin. This drives the gate of the charge control N-ch FET.

2

3

4

C

Charge Time Delay pin. The capacitor connected to this pin sets the delay.

Positive supply voltage input pin. Connect to positive terminal of the cell.

Ground pin. Connect to negative terminal of the cell.

DLY

CC

5

V

6

GND

MAXIMUM RATINGS

SYMBOL

PARAMETER

MIN.

MAX.

UNIT

V

Input voltage

CF pin voltage

VM pin voltage

–0.3

+12

IN

V

– 28

V

+ 0.3

V

CF(max)

VM(max)

CC

– 28

+ 0.3

V

T

Operating ambient temperature range

Storage temperature

–40

+85

°C

mW

opr

T

stg

–40

–

+125

150

P

Power dissipation

D

3

2003 Oct 29

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

ELECTRICAL CHARACTERISTICS

Characteristics measured with T

= 25 °C, unless otherwise specified.

amb

SYMBOL

PARAMETER

CONDITIONS

MIN.

1.5

–

TYP.

–

MAX.

10

UNIT

V

DD1

Operating input voltage

Supply current

V

– GND; Voltage defined as V to VM

CC

DD

I

= 3.9 V; VM = 0 V

= 2.0 V

3.0

0.3

–

8.0

mA

V

DD

SLP

Sleep current

–

0.6

V

Minimum operating voltage for 0 V

charging

– GND

–

1.2

DD(min)

OV1(th)

SA57608Y

SA57608B

4.30

4.255

4.27

4.30

4.25

4.255

–

4.35

4.280

4.295

4.350

4.275

4.280

180

150

180

200

2.30

150

75

4.40

4.305

4.32

4.40

4.3

V

SA57608C

SA57608D

SA57608E

SA57608G

SA57608Y

SA57608B

SA57608C

SA57608D

SA57608E

SA57608G

SA57608Y

SA57608B

SA57608C

SA57608D

SA57608E

SA57608G

SA57608Y

SA57608B

SA57608C

SA57608D

SA57608E

SA57608G

V

T

= 0 °C 50 °C;

amb

V

Over-charge voltage threshold

V

BATT

: L → H

V

4.305

–

V

mV

V

–

V

Over-charge hysteresis

V

CC

V

CC

V

VM

: H → L

: L → H

OV1(hyst)

–

2.23

2.242

2.23

2.242

120

45

2.37

2.358

2.37

2.358

180

105

230

130

4.22

93

V

UV(th)

Over-discharge threshold voltage

V

mV

V

170

70

200

100

4.17

77

V

Overcurrent threshold

OC1(th)

70

Release voltage for over-discharge

Over-charge delay time

4.12

61

OV(rel)

OV(DLY)

OV

t

C

= 0.01 µF; V = 4.0 V to 4.4 V

ms

V

TD

CC

Over-discharge delay time

Over-current delay time

Short protection voltage

Short detect delay time

V

CC

= 3.6 V to 2.2 V

5

8

11

VM : 0 V → 0.5 V

9

13

17

OC(DLY)

V

OC2

V

CC

V

CC

V

CC

= 3.0 V

V

–1.2

V

–0.9

V

CC

–0.6

CC

t

= 3.0 V

–

5

50

ms

kW

DLY(SC)

R

Reset resistance for excess current

protection

= 3.6 V; VM = 1.0 V

50

100

150

SC

V

Nch ON voltage of CFET

Pch ON voltage of CFET

Nch ON voltage of DFET

Pch ON voltage of DFET

I

= 50 mA; V = 4.4 V

–

0.35

3.7

0.2

3.7

0.5

–

V

CFET(off)

CFET(on)

DFET(off)

DFET(on)

OL

OH

OL

OH

CC

= 50 mA; V = 3.9 V

3.4

–

CC

= 50 mA; V = 2.2 V

0.5

–

CC

= 50 mA; V = 3.9 V

3.4

CC

4

2003 Oct 29

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

as that provided by the SA57611. This provides two levels of

TECHNICAL DISCUSSION

overcharge protection, with the primary protection of the external

charge control circuit and the backup protection from the battery

pack’s protection circuit. The charge termination circuit will be set to

stop charging at a level around 50 mV less than the overvoltage

threshold voltage of the battery pack’s own protection circuit.

Lithium cell safety

Lithium-ion and lithium-polymer cells have a higher energy density

than that of nickel-cadmium or nickel metal hydride cells and have a

much lighter weight. This makes the lithium cells attractive for use in

portable products. However, lithium cells require a protection circuit

within the battery pack because certain operating conditions can be

hazardous to the battery or the operator, if allowed to continue.

Lithium cell operating characteristics

The internal resistance of lithium cells is in the 100 mΩ range,

compared to the 5–20 mΩ of the nickel-based batteries. This makes

the Lithium-ion and polymer cells better for lower battery current

applications (less than 1 ampere) as found in cellular and wireless

telephones, palmtop and laptop computers, etc.

Lithium cells have a porous carbon or graphite anode where lithium

ions can lodge themselves in the pores. The lithium ions are

separated, which avoids the hazards of metallic lithium.

If the lithium cell is allowed to become overcharged, metallic lithium

plates out onto the surface of the anode and volatile gas is

generated within the cell. This creates a rapid-disassembly hazard

The average operating voltage of a lithium-ion or polymer cell is

3.6 V as compared to the 1.2 V of NiCd and NiMH cells. The typical

discharge curve for Lithium cell is shown in Figure 3.

(the battery ruptures). If the cell is allowed to over-discharge (V

less than approximately 2.3 V), then the copper metal from the

cell

cathode goes into the electrolyte solution. This shortens the cycle

life of the cell, but presents no safety hazard. If the cell experiences

excessive charge or discharge currents, as happens if the wrong

charger is used, or if the terminals short circuit, the internal series

resistance of the cell creates heating and generates the volatile gas

which could rupture the battery.

V

OV

4.0

3.0

2.0

The protection circuit continuously monitors the cell voltage for an

overcharged condition or an overdischarged condition. It also

continuously monitors the output for an overcurrent condition. If

any of these conditions are encountered, the protection circuit opens

a series MOSFET switch to terminate the abnormal condition. The

lithium cell protection circuit is placed within the battery pack very

close to the cell.

V

UV

50

100

Charging control versus battery protection

NORMALIZED CELL CAPACITY (%)

The battery pack industry does not recommend using the pack’s

internal protection circuit to end the charging process. The external

battery charger should have a charge termination circuit in it, such

SL01553

Figure 3. Lithium discharge curve.

5

2003 Oct 29

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

Charging Lithium cells

SA57608 OPERATION

The lithium cells must be charged with a dedicated charging IC such

as the NE57600. These dedicated charging ICs perform a

current-limited, constant-voltage charge, as shown in Figure 4.

The SA57608 continuously monitors the terminal voltage and battery

pack current of a single Li-ion battery pack. Li-ion cells must be

maintained within a set of a very defined operating conditions to

operate safely and with with a long life. If the cell voltage exceeds

the cell’s full-charge voltage, the charge current is interrupted. If the

cell voltage falls below the overdischarge rating of the cell, the

discharge current is interrupted. Also, whenever the discharge

The charger IC begins charging with a current that is typically the

rating of the cell (1C) or the milliampere rating of the cell. As the cell

approaches its full-charge voltage rating (V ), the current entering

the cell decreases, and the charger IC provides a constant voltage.

When the charge current falls below a preset amount, 50 mA for

example, the charge is discontinued.

OV

current exceeds the threshold voltage across the R

two MOSFETs, the short-circuit current is interrupted.

of the

DS(on)

If charging is begun below the overdischarged voltage rating of the

cell, it is important to slowly raise the cell voltage up to this

overdischarged voltage level. This is done by a reconditioning

charge. A small amount of current is provided to the cell (50 mA for

example), and the cell voltage is allowed a period of time to rise to

the overdischarged voltage. If the cell voltage recovers, then a

normal charging sequence can begin. If the cell does not reach the

overdischarged voltage level, then the cell is too damaged to charge

and the charge is discontinued.

V

CC

V

CC

OV

DELAY

CONTROL

CF

OV

UV

C

DLY

V

REF

To take advantage of the larger energy density of lithium cells it is

important to allow enough time to completely charge the cell . When

the charger switches from constant current to constant voltage

charge (Point B, Figure 4) the cell only contains about 80 percent of

its full capacity. When the cell is 100 mV less than its full rated

charge voltage the capacity contained within the cell is 95 percent.

Hence, allowing the cell to slowly complete its charge takes

advantage of the larger capacity of the lithium cells.

GND

V–

CHARGER

DETECTOR

V

CC

UV

DELAY

CONTROL

DF

OC REF

SL01579

Figure 5. SA57608 block diagram.

1.0

Overvoltage condition

When the cell’s terminal voltage exceeds the value of V

,

OV1

measured from V (pin 5) to GND (pin 6), the overvoltage time

CC

0.5

CONSTANT

CURRENT

CONSTANT

VOLTAGE

delay is initiated. After this time has elapsed, the gate of the charge

MOSFET (CF, pin 3) is driven LOW and the charge current is

interrupted. The terminal voltage of the cell may immediately fall due

to the amount of the charge current times the series resistance of

the Li-ion cell (I

again until the cell voltage has fallen below V

is detected across the battery pack terminals. A load is detected

when the VM pin (pin 2) is drawn 0.7 V above the cell’s negative

terminal (GND, pin 6).

× R

). The charge MOSFET will not turn on

ESR

chg

1.0

2.0

, or when a load

OV(rel)

TIME (HOURS)

Vov

The timing capacitor C

the overvoltage threshold (V

(pin 4) provides a time period between

DLY

4.0

) being exceeded and when the

OV1

charge MOSFET is turned off. Its timing period is approximately:

= C (V – 0.7 V) / 0.43 µA (Equation 1)

The variation in timing is approximately ±16 percent.

Point B

t

DLY

CC

3.0

1.0

2.0

TIME (HOURS)

SL01554

Figure 4. Lithium Cell charging Curves

6

2003 Oct 29

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

If the battery pack is being charged, and the cell’s voltage exceeds

the overvoltage threshold, then the charge MOSFET is turned OFF

(FET towards the pack’s external terminal). The cell’s voltage must

Undervoltage condition

When the cell voltage falls below the overdischarge threshold,

(V

UV1

), as measured between V (pin 5) and GND (pin 6), the gate

CC

fall lower than the overvoltage hysteresis voltage (V ) before

OV(Hyst)

the charge MOSFET is again turned ON.

of the discharge MOSFET (DF, pin 1) is brought LOW (OFF) after an

internal time delay. The SA57608 then assumes a sleep condition

where its I assumes a very low state (I

) The gate is then

CC

CC(SLP)

If the battery pack is being discharged and the undervoltage

threshold (V ) is exceeded, then the discharge MOSFET is

turned OFF. It will not run back ON until a charger is applied to the

brought HIGH (ON) when a charge current is detected, or when the

VM pin (pin 2) is brought to 0.7 V higher than the negative terminal

of the cell (GND, pin 6) or when the cell voltage is higher than the

UV(Th)

pack’s external terminals and the cell’s voltage rises above the

hysteresis voltage (V

).

UV2

undervoltage hysteresis voltage (V

).

UV(Hyst)

When the battery pack is being discharged, the load current causes

the voltage across the discharge MOSFET to increase past the

Discharge overcurrent condition

If a discharge overcurrent condition is experienced as seen when a

short-circuit is experienced across the battery terminals, the

overcurrent threshold voltage (V

), then the discharge

OC(TH)

MOSFET is turned OFF after a fixed 7–18 ms delay. If short-circuit

is placed across the pack’s terminals, then the discharge MOSFET

is turned OFF after a 100–300 µs time delay to avoid damaging the

MOSFETs.

SA57608 views a high voltage across the MOSFET’s R

. If this

DS(on)

voltage exceeds the threshold voltage (V ), the discharge gate is

SC

brought to a LOW condition (OFF) after an internally set of time

delays are exceeded. If the overcurrent is LOW, then the t

is

SC1

enacted. If the the overcurrent is higher, as experienced in a hard

short-circuit, the time delay is less than 400 ns. This prevents the

MOSFETs from failing from an FBSOA failure.

The R-C filter on the V pin

CC

One needs to place an R-C filters on the V pin. It is to primarily

CC

shield the IC from electrostatic occurrences and spikes on the

terminals of the battery pack. A secondary need is during the

occurrence of a short-circuit across the battery pack terminals. Here,

the Li-ion cell voltage could collapse and cause the IC to enter an

unpowered state. The R-Cs then provide power during the first

instant of the short circuit and allow the IC to turn OFF the discharge

MOSFET. The IC can then enter an unpowered state. Lastly, the

R-C filter filters any noise voltage caused by noisy load current.

The gate of the discharge MOSFET is turned on again only when

the voltage of the VM pin is allowed to fall within the 0.7 volts of the

negative terminal of the cell (GND, Pin 6). If the short-circuit

persists, the gate of the discharge MOSFET is immediately brought

LOW (OFF) again until the short-circuit condition is again removed.

APPLICATION INFORMATION

The typical single-cell lithium-ion or polymer protection circuit based

upon the SA57608 is seen in Figure 6.

The values shown in Figure 6 are good for these purposes.

Selecting the Optimum MOSFETs:

For a single-cell battery pack, a logic-level MOSFET should be

used. These MOSFETs have turn-on thresholds of 0.9 V and are

considered full-ON at 4.5 V VGS. Some problem may be

encountered in not having enough gate voltage to fully turn-ON the

series MOSFETs over the battery pack’s entire operating voltage. If

one deliberately selects an N-Channel MOSFET with a much

V+

100 Ω

5

V

C

CC

0.01 µF

SA57608

0.1 µF

4

6

2

greater current rating, a lower R

attained.

over the entire range can be

DS(on)

VM

DLY

Li-ION

CELL

The MOSFETs should have a voltage rating greater than 20 V and

should have a high avalanche rating to survive any spikes

generated across the battery pack terminals.

GND

DF

CF

3

1

The current rating of the MOSFETs should be greater than four

times the maximum “C-rating” of the cells. The current rating,

though, is more defined by the total series resistance of the battery

pack. The total resistance of the battery pack is given by Equation 2.

1 kΩ

0.1 µF

V–

R

= R

+ R

cell

(Equation 2)

bat(tot)

DS(on)

The total pack resistance is typically determined by the system

requirements. The total pack resistance directly determines how

much voltage droop will occur during pulses in load current.

DISCHARGE

FET

CHARGE

FET

SL01570

Figure 6. Typical protection circuit

Another consideration is the forward-biased safe operating area of

the MOSFET. During a short-circuit, the discharge current can easily

reach 10–15 times the “C-rating” of the cells. The MOSFET must

survive this current prior to the discharge MOSFET can be turned

OFF. So having an FBSOA envelope that exceeds 20 amperes for

5 ms would be safe.

The SA57608 drives the series N-Channel MOSFETs to states

determined by the cell’s voltage and the battery pack load current.

During normal periods of operation, both the discharge and charge

MOSFETs are in the ON state, thus allowing bidirectional current

flow.

7

2003 Oct 29

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

PACKING METHOD

GUARD

BAND

TAPE

TAPE DETAIL

REEL

ASSEMBLY

COVER TAPE

CARRIER TAPE

BARCODE

LABEL

BOX

SL01305

8

2003 Oct 29

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

Plastic small outline package; 6 leads; body width 1.8 mm

SOP004

9

2003 Oct 29

Philips Semiconductors

Product data

One-cell Lithium-ion battery protection with

over/undercharge and overcurrent protection

SA57608

REVISION HISTORY

Rev

Date

Description

_1

yyyymmdd

Product data (9397 750 12192). ECN 853-2298 30337 of 09 September 2003.

Supersedes data of 2001 Oct 03 (9397 750 08994).

Modifications:

• Change package outline version to SOP004 in Ordering information table and Package outline sections.

_1

20011003

Product data (9397 750 08994). ECN 853-2298 27198 of 03 October 2001.

Data sheet status

Product

status

Definitions

[1]

Level

Data sheet status

[2] [3]

I

Objective data

Development

This data sheet contains data from the objective specification for product development.

Philips Semiconductors reserves the right to change the specification in any manner without notice.

II

Preliminary data

Qualification

Production

This data sheet contains data from the preliminary specification. Supplementary data will be published

at a later date. Philips Semiconductors reserves the right to change the specification without notice, in

order to improve the design and supply the best possible product.

III

Product data

This data sheet contains data from the product specification. Philips Semiconductors reserves the

right to make changes at any time in order to improve the design, manufacturing and supply. Relevant

changes will be communicated via a Customer Product/Process Change Notification (CPCN).

[1] Please consult the most recently issued data sheet before initiating or completing a design.

[2] The product status of the device(s) described in this data sheet may have changed since this data sheet was published. The latest information is available on the Internet at URL

http://www.semiconductors.philips.com.

[3] For data sheets describing multiple type numbers, the highest-level product status determines the data sheet status.

Definitions

Short-form specification — The data in a short-form specification is extracted from a full data sheet with the same type number and title. For detailed information see

the relevant data sheet or data handbook.

Limitingvaluesdefinition— Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 60134). Stress above one or more of the limiting

values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given

in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability.

Application information — Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors make no

representation or warranty that such applications will be suitable for the specified use without further testing or modification.

Disclaimers

Life support — These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be

expected to result in personal injury. Philips Semiconductors customers using or selling these products for use in such applications do so at their own risk and agree

to fully indemnify Philips Semiconductors for any damages resulting from such application.

Right to make changes — Philips Semiconductors reserves the right to make changes in the products—including circuits, standard cells, and/or software—described

or contained herein in order to improve design and/or performance. When the product is in full production (status ‘Production’), relevant changes will be communicated

viaaCustomerProduct/ProcessChangeNotification(CPCN).PhilipsSemiconductorsassumesnoresponsibilityorliabilityfortheuseofanyoftheseproducts,conveys

nolicenseortitleunderanypatent, copyright, ormaskworkrighttotheseproducts, andmakesnorepresentationsorwarrantiesthattheseproductsarefreefrompatent,

copyright, or mask work right infringement, unless otherwise specified.

Koninklijke Philips Electronics N.V. 2003

Contact information

For additional information please visit

http://www.semiconductors.philips.com.

Fax: +31 40 27 24825

Date of release: 10-03

9397 750 12192

For sales offices addresses send e-mail to:

sales.addresses@www.semiconductors.philips.com.

Document order number:

Philips

Semiconductors

10

2003 Oct 29


型号：	SA57608DD
厂家：	NXP
描述：	暂无描述电池过电流保护
文件：	总10页 (文件大小：112K)
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SA57608DD [NXP]

相关型号：

SA57608DD-G

SA57608ED-G

SA57608GD

SA57608XD

SA57608YD

SA57608YD-G

SA576D

SA576D

SA576D-T

SA576D-T

SA576D-T

SA576N