MAXIM DS2762 Technical data

C

PS

C

C

www.maxim-ic.com

High-Precision Li+ Battery Monitor With Alerts

GENERAL DESCRIPTION

The DS2762 high-precision Li+ battery monitor is a
data-acquisition, information-storage, and safety­protection device tailored for cost-sensitive battery
pack applications. This low-power device integrates
precise temperature, voltage, and current
measurement, nonvolatile (NV) data storage, and Li+
protection into the small footprint of either a TSSOP
package or flip-chip package. The DS2762 is a key
component in applications including remaining
capacity estimation, safety monitoring, and battery­specific data storage.

PIN CONFIGURATIONS

TOP VIEW

16

1

1

C

PLS

2

2

3

2

D

SNS

SNS

SNS

(top view – bumps on bottom)

4

5

6

DQ

7

8

IS2

TSSOP

1 2 3 4

SNS

PLS DC DQ

SNS

C IS2

PROBE

VSS

IS1

V

IN

PROBE

V

PIO PS

DD

V

SS

FLIP CHIP

VIN

15

V

DD

14

PIO

13

V

SS

12

V

SS

11

V

SS

10

9

IS1

A

B

C

D

E

F

DS2762

FEATURES

§ Li+ Safety Circuit

Overvoltage Protection
Overcurrent/Short-Circuit Protection
Undervoltage Protection

§ Host Alerted When Accumulated Current or
Temperature Exceeds User-Selectable Limits

§ 0V Battery Recovery Charge

§ Available in Two Configurations:

Internal 25mW Sense Resistor
External User-Selectable Sense Resistor

§ Current Measurement

12-Bit Bidirectional Measurement
Internal Sense Resistor Configuration:

0.625mA LSB and ±1.9A Dynamic Range

External Sense Resistor Configuration:

15.625mV LSB and ±64mV Dynamic Range

§ Current Accumulation:

Internal Sense Resistor: 0.25mAhr LSB
External Sense Resistor: 6.25mVhr LSB

§ Voltage Measurement with 4.88mV Resolution

§ Temperature Measurement Using Integrated

Sensor with 0.125°C Resolution

§ System Power Management and Control
Feature Support

§ 32 Bytes of Lockable EEPROM

§ 16 Bytes of General-Purpose SRAM

§ Dallas 1-Wire

Device Address

§ Low-Power Consumption:

Active Current: 60mA typ, 90mA max
Sleep Current: 1mA typ, 2mA max

APPLICATIONS

PDAs
Cell Phones/Smartphones
Digital Cameras

ORDERING INFORMATION

PART TEMP RANGE PIN-PACKAGE

®

Interface with Unique 64-Bit

DS2762BE+ -20°C to +70°C 16 TSSOP

1-Wire is registered trademark of Dallas Semiconductor.

Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device
may be simultaneously available through various sales channels. For information about device errata, click here: www.maxim-ic.com/errata

Selector Guide appears at end of data sheet, for additional
options.

.

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REV: 010906

DS2762 High-Precision Li+ Battery Monitor With Alerts

ABSOLUTE MAXIMUM RATINGS

Voltage Range on PLS and CC Pin, Relative to VSS
Voltage Range on PIO Pin, Relative to V
Voltage Range on Any Other Pin, Relative to V

-0.3V to +12V

SS

-0.3V to +6V

SS

Continuous Internal Sense Resistor Current
Pulsed Internal Sense Resistor Current

±50A for <100µs/s, <1000 pulses
Operating Temperature Range -40°C to +85°C
Storage Temperature Range -55°C to +125°C
Soldering Temperature See IPC/JEDEC J-STD-020A Specification

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is
not implied. Exposure to the absolute maximum rating conditions for extended periods may affect device.

-0.3V to +18V

±2.5A

RECOMMENDED DC OPERATING CONDITIONS

(2.5V £ VDD £ 5.5V, TA = -20°C to +70°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Supply Voltage VDD (Note 1) 2.5 5.5 V

Data Pin DQ (Note 1) -0.3 +5.5 V

DC ELECTRICAL CHARACTERISTICS

(2.5V £ VDD £ 5.5V, TA = -20°C to +70°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Active Current I

Sleep Mode Current I

DQ = VDD, normal operation 60 90

ACTIVE

SLEEP

DQ = 0V, no activity, PS floating

1 2

mA

mA

Input Logic High: DQ, PIO VIH (Note 1) 1.5 V

(Note 1) VDD - 0.2V V

Input Logic High: PS

V

IH

Input Logic Low: DQ, PIO VIL (Note 1) 0.4 V

(Note 1) 0.2 V

Input Logic Low: PS

Output Logic High: CC

Output Logic High: DC

Output Logic Low: CC, DC

Output Logic Low: DQ, PIO V

DQ Pulldown Current IPD 1

Input Resistance: VIN R

V

IL

V

OH

V

OH

V

OL

OL

IOH = -0.1mA (Note 1) V

IOH = -0.1mA (Note 1) VDD - 0.4V V

IOL = 0.1mA (Note 1) 0.4 V

IOL = 4mA (Note 1) 0.4 V

- 0.4V V

PLS

mA

IN

5

MW

Internal Current-Sense Resistor R

DQ Low to Sleep time t

SNS

SLEEP

+25°C 20 25 30

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mW

2.1 s

DS2762 High-Precision Li+ Battery Monitor With Alerts

ELECTRICAL CHARACTERISTICS: PROTECTION CIRCUITRY

(2.5V £ VDD £ 5.5V, TA = 0°C to +50°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Overvoltage Detect VOV (Notes 1, 2)

V

4.250 4.275 4.300

Charge Enable VCE (Note 1) 4.10 4.15 4.20 V

Undervoltage Detect VUV (Note 1) 2.5 2.6 2.7 V

4.325 4.350 4.375

Overcurrent Detect I

OC

(Note 3) 1.8 1.9 2.0 A

Overcurrent Detect VOC (Note 1, 4) 45 47.5 50 mV

Short-Circuit Detect ISC (Note 3) 5.0 8.0 11 A

Short-Circuit Detect V

Overvoltage Delay t

Undervoltage Delay t

Overcurrent Delay t

Short-Circuit Delay t

Test Threshold V

Test Current I

SC

0.8 1 1.2 s

OVD

90 100 110 ms

UVD

5 10 20 ms

OCD

SCD

TP

TST

(Note 1) 150 200 250 mV

160 200 240

ms

0.5 1.0 1.5 V

10 20 40

mA

Recovery Charge Current IRC (Note 5) 0.5 1 2 mA

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DS2762 High-Precision Li+ Battery Monitor With Alerts

ELECTRICAL CHARACTERISTICS: TEMPERATURE, VOLTAGE, CURRENT

(2.5V £ VDD £ 5.5V, TA = -20°C to +50°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Temperature Resolution T

Temperature Full-Scale Magnitude T

Temperature Error T

Voltage Resolution V

Voltage Full-Scale Magnitude V

Voltage Offset Error V

Voltage Gain Error V

Current Resolution I

Current Full-Scale Magnitude I

Current Offset Error I

Current Gain Error I

Accumulated Current Resolution q

LSB

FS

ERR

LSB

FS

OERR

GERR

LSB

FS

OERR

GERR

CA

0.125

127

(Note 6)

±3 °C

°C

°C

4.88 mV

4.75 V

(Note 7) 1 LSB

5 %

(Note 3) 0.625 mA

(Note 4) 15.625

mV

(Notes 3, 4) 1.9 2.56 A

(Note 8) 64 mV

(Note 9) 1 LSB

(Notes 3, 10, 14) 3

%

(Note 4) 1

(Note 3) 0.25 mAhr

(Note 4) 6.25 µVhr

Current Sampling Frequency f

SAMP

t

ERR1

1456 Hz

(Note 11)

Internal Timebase Accuracy

t

ERR2

(Note 11)

EEPROM RELIABILITY SPECIFICATION

(2.5V £ VDD £ 5.5V, TA = -20°C to +70°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Copy to EEPROM Time t

EEPROM Copy Endurance N

EEC

EEC

2 10 ms

(Note 12) 25,000 cycles

±1 ±3

±6.5

%

%

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DS2762 High-Precision Li+ Battery Monitor With Alerts

ELECTRICAL CHARACTERISTICS: 1-WIRE INTERFACE

(2.5V £ VDD £ 5.5V, TA = -20°C to +70°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Time Slot t

Recovery Time t

Write 0 Low Time t

Write 1 Low Time t

Read Data Valid t

Reset Time High t

Reset Time Low t

Presence Detect High t

Presence Detect Low t

SWAP Timing Pulse Width t

SWAP Timing Pulse Falling Edge to DC
Release

SWAP Timing Pulse Rising Edge to DC
Engage

60 120

SLOT

1

REC

60 120

LOW0

1 15

LOW1

15

RDV

480

RSTH

480 960

RSTL

15 60

PDH

60 240

PDL

SWL

t

SWOFF

t

SWON

(Note 13) 0 1

(Note 13) 0 1

0.2 120

ms

ms

ms

ms

ms

ms

ms

ms

ms

ms

ms

ms

DQ Capacitance CDQ 60 pF

Note 1:

Note 2:

Note 3:

Note 4:

Note 5:

Note 6:

Note 7:
Note 8:

Note 9:
Note 10:

Note 11:

Note 12:

Note 13:

Note 14:

All voltages are referenced to V

See the Selector Guide section to determine the corresponding part number for each V

Internal current-sense resistor configuration.

External current-sense resistor configuration.

Test conditions are PLS = 4.1V, V

Self-heating due to output pin loading and sense resistor power dissipation can alter the reading from ambient conditions.

Voltage offset measurement is with respect to V
The current register supports measurement magnitudes up to 2.56A using the internal sense resistor option and 64mV with the

external resistor option. Compensation of the internal sense resistor value for process and temperature variation can reduce the
maximum reportable magnitude to 1.9A.

Current offset error null to ±1LSB typically requires 3.5s in-system calibration by user.
Current gain error specification applies to gain error in converting the voltage difference at IS1 and IS2, and excludes any error

remaining after the DS2762 compensates for the internal sense resistor’s temperature coefficient of 3700ppm/°C to an accuracy
of ±500ppm/°C. The DS2762 does not compensate for external sense resistor characteristics, and any error terms arising from
the use of an external sense resistor should be taken into account when calculating total current measurement error.

Typical value for t
for -20°C to +70°C.

Four-year data retention at +70°C.

Typical load capacitance on DC and CC is 1000pF.

Error at time of shipment from Dallas Semiconductor is 3% max. Board mounting processes may cause the current gain error
to widen to as much as 10% for devices with the internal sense resistor option. Contact factory for on-board recalibration
procedure for devices with the internal sense resistor option to improve accuracy.

is specified at 3.6V and +25°C, max value is specified for 0°C to +50°C. Max value for t

ERR1

.

SS

value.

OV

= 2.5V. Maximum current for conditions of PLS = 15V, VDD = 0V is 10mA.

DD

at +25°C.

OV

is specified

ERR2

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PIN DESCRIPTION

PIN

TSSOP

FLIP

CHIP

1 C1

2 B1 PLS

3 B2

4, 5, 6 A3 SNS

7 B4 DQ

SYMBOL FUNCTION

CC

DC

DS2762 High-Precision Li+ Battery Monitor With Alerts

Charge Protection Control Output. Controls an external P-channel high-side charge
protection FET.

Battery Pack Positive Terminal Input. The DS2762 monitors the pack plus terminal
through PLS to detect overcurrent and overload conditions, as well as the presence of a
charge source. Additionally, a charge path to recover a deeply depleted cell is provided
from PLS to V
connected to PLS is discharged internally to V
reliable detection of a valid charge source. For details of other internal connections to
PLS and associated conditions see the Li+ Protection Circuitry section.

Discharge Protection Control Output. Controls an external P-channel high-side
discharge protection FET.

Sense Resistor Connection. Connect to the negative terminal of the battery pack. In
the internal sense resistor configuration, the sense resistor is connected between V
and SNS.

Data Input/Out. 1-Wire data line. Open-drain output driver. Connect this pin to the DATA
terminal of the battery pack. Pin has an internal 1mA pulldown for sensing disconnection.

. In sleep mode (with SWEN = 0), any capacitance or voltage source

DD

through 200µA (nominal) to assure

SS

SS

8 C4 IS2

9 D4 IS1

10 E4

11, 12, 13 F3

14 E2

15 E1 VDD

16 D1 VIN

— C2

— D2

Probe

Probe

PS

V

SS

PIO

SNS

V

SS

Current-Sense Input. This pin is internally connected to SNS through a 4.7kW resistor.

Current-Sense Input. This pin is internally connected to V

through a 4.7kW resistor.

SS

Connect a 0.1mF capacitor between IS1 and IS2 to complete a lowpass input filter.

Power Switch Sense Input. The device wakes up from sleep mode when it senses the
closure of a switch to V

Device Ground. Connect directly to the negative terminal of the Li+ cell. For the external
sense resistor configuration, connect the sense resistor between V

on this pin. Pin has an internal 1mA pullup to VDD.

SS

and SNS.

SS

Programmable I/O Pin. Can be configured to be used to control and monitor user-
defined external circuitry or as an interrupt output to alert the host when preset current
accumulator or temperature limits are exceeded. Open drain to V

.

SS

Power-Supply Input. Connect to the positive terminal of the Li+ cell through a
decoupling network.

Voltage Sense Input. The voltage of the Li+ cell is monitored through this input pin. This
pin has a weak pullup to V

DD

.

Do not connect.

Do not connect.

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DS2762 High-Precision Li+ Battery Monitor With Alerts

SS

CC D

Figure 1. Block Diagram

DQ

THERMAL

SENSE

V

+

IS1

-

IS2

PLS

PS

SNS

1-Wire

INTERFACE

AND

ADDRESS

VOLTAGE

REFERENCE

MUX

INTERNAL SENSE RESISTOR

CONFIGURATION ONLY

25mW

IS2 IS1

DS2762

ADC

REGISTERS AND

USER MEMORY

LOCKABLE EEPROM

SRAM

TEMPERATURE

VOLTAGE

CURRENT

ACCUM. CURRENT

STATUS/CONTROL

Li+ PROTECTION

CHIP GROUND

TIMEBASE

PIO

C

V

DETAILED DESCRIPTION

The DS2762 high-precision Li+ battery monitor is a data-acquisition, information-storage, and safety-protection
device tailored for cost-sensitive battery pack applications. This low-power device integrates precise temperature,
voltage, and current measurement, nonvolatile (NV) data storage, and Li+ protection into the small footprint of
either a TSSOP package or flip-chip package. The DS2762 is a key component in applications including remaining
capacity estimation, safety monitoring, and battery-specific data storage.

Through its 1-Wire interface, the DS2762 gives the host system read/write access to status and control registers,
instrumentation registers, and general-purpose data storage. Each device has a unique factory-programmed 64-bit
net address that allows it to be individually addressed by the host system, supporting multibattery operation.

The DS2762 is capable of performing temperature, voltage, and current measurement to a resolution sufficient to
support process monitoring applications such as battery charge control, remaining capacity estimation, and safety
monitoring. Temperature is measured using an on-chip sensor, eliminating the need for a separate thermistor.
Bidirectional current measurement and accumulation are accomplished using either an internal 25mW sense
resistor or an external device. The DS2762 also features a programmable I/O pin that allows the host system to
sense and control other electronics in the pack, including switches, vibration motors, speakers, and LEDs. This pin
may also be used to alert the host when preset accumulated current or temperature limits are exceeded.

Three types of memory are provided on the DS2762 for battery information storage: EEPROM, lockable EEPROM,
and SRAM. EEPROM memory saves important battery data in true NV memory that is unaffected by severe battery
depletion, accidental shorts, or ESD events. Lockable EEPROM becomes ROM when locked to provide additional
security for unchanging battery data. SRAM provides inexpensive storage for temporary data.

7 of 25

Figure 2. Application Example

C

D

PS

0

102 x 2

PACK+

1kW

150W

1

150W

2

DATA

PACK-

NOTE 1: R
CONFIGURATIONS ONLY.
NOTE 2: R
CONFIGURATIONS ONLY.

IS PRESENT FOR EXTERNAL SENSE RESISTOR

SNS

IS PRESENT FOR INTERNAL SENSE RESISTOR

SNS-INT

1kW

PLS

SNS
SNS
SNS
DQ
IS2

DS2762

C

C

V

V

PIO

V
V
V

IS1

104

IN

DD

SS

SS

SS

DS2762 High-Precision Li+ Battery Monitor With Alerts

BAT+

1kW

R

SNS

(NOTE 1)

SNS

IS2 IS1

150W

PIO

104

PS

4.7kW

BAT-

R

SNS-INT

(NOTE 2)

VSS

R

R

KS

4.7kW

VOLTAGE

SENSE

DS2762

KS

4.7kW

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