LTC1760

13

1760fa

1

Overview ............................................................................................................................................................................................. 13

2

The SMBus Interface .......................................................................................................................................................................... 13

2.1

SMBus Interface Overview............................................................................................................................................................... 13

2.2

Data Bit Definition of Supported SMBus Functions. ......................................................................................................................... 14

2.3

Description of Supported SMBus Functions .................................................................................................................................... 17

2.3.1

BatterySystemState() (0

×01) ....................................................................................................................................................... 17

2.3.2

BatterySystemStateCont() (0

×02)................................................................................................................................................ 18

2.3.3

BatterySystemInfo() (0

×04) ......................................................................................................................................................... 19

2.3.4

LTC() (0

×3C) ................................................................................................................................................................................ 20

2.3.5

BatteryMode() (0

×03) .................................................................................................................................................................. 20

2.3.6

Voltage() (0

×09)........................................................................................................................................................................... 20

2.3.7

Current() (0

×0A) .......................................................................................................................................................................... 21

2.3.8

ChargingCurrent() (0

×14) ............................................................................................................................................................ 21

2.3.9

ChargingVoltage() (0

×15) ............................................................................................................................................................ 21

2.3.10

AlarmWarning() (0

×16)................................................................................................................................................................ 21

2.3.11

AlertResponse() ........................................................................................................................................................................... 22

2.4

SMBus Dual Port Operation ............................................................................................................................................................. 22

2.5

LTC1760 SMBus Controller Operation.............................................................................................................................................. 23

2.6

LTC1760 SMBALERT Operation........................................................................................................................................................ 26

3

Charging Algorithm Overview ............................................................................................................................................................. 26

3.1

Wake-Up Charging Initiation ............................................................................................................................................................ 26

3.2

Wake-Up Charging Termination ....................................................................................................................................................... 26

3.3

Wake-Up Charging Current and Voltage Limits ................................................................................................................................ 27

3.4

Controlled Charging Initiation .......................................................................................................................................................... 27

3.5

Controlled Charging Termination...................................................................................................................................................... 27

3.6

Controlled Charging Current Programming...................................................................................................................................... 28

3.6.1

Current Limits When Charging A Single Battery........................................................................................................................... 28

3.6.2

Current Limits When Charging Two Batteries (TURBO Mode Disabled) ....................................................................................... 28

3.6.3

Current Limits When Charging Two Batteries (TURBO Mode Enabled)......................................................................................... 29

3.7

Controlled Charging Voltage Programming...................................................................................................................................... 29

4

System Power Management Algorithm and Battery Calibration .......................................................................................................... 29

4.1

Turning Off System Power ............................................................................................................................................................... 29

4.2

Power-By Algorithm When No Battery is Being Calibrated ............................................................................................................... 29

4.3

Power-By Algorithm When a Battery is Being Calibrated.................................................................................................................. 30

4.4

Power-By Reporting ......................................................................................................................................................................... 30

5

Battery Calibration (Conditioning) ....................................................................................................................................................... 30

5.1

Selecting a Battery to be Calibrated.................................................................................................................................................. 30

5.2

Initiating Calibration of Selected Battery .......................................................................................................................................... 31

5.3

Terminating Calibration of Selected Battery...................................................................................................................................... 31

6

MODE Pin Operation ........................................................................................................................................................................... 31

6.1

Stand Alone Charge Indication ......................................................................................................................................................... 31

6.2

Hardware Charge Inhibit .................................................................................................................................................................. 32

6.3

Charging When SCL and SDA are Low............................................................................................................................................. 32

6.4

Charging With an SMBus Host......................................................................................................................................................... 32

7

Battery Charger Controller ................................................................................................................................................................. 32

7.1

Charge MUX Switches...................................................................................................................................................................... 33

7.2

Dual Charging .................................................................................................................................................................................. 33

8

PowerPath Controller ......................................................................................................................................................................... 33

8.1

Autonomous PowerPath Switching.................................................................................................................................................. 34

8.2

Short-Circuit Protection ................................................................................................................................................................... 34

8.3

Emergency Turn-Off ......................................................................................................................................................................... 34

8.4

Power-Up Strategy ........................................................................................................................................................................... 34

9

The Voltage DAC Block ...................................................................................................................................................................... 34

10

The Current DAC Block ........................................................................................................................................................................ 35

(For Operation Section)

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