LTC1760

12

1760f

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 .................................................................................................................................... 16

2.3.1

BatterySystemState() ('h01) ........................................................................................................................................................ 16

2.3.2

BatterySystemStateCont() ('h02) ................................................................................................................................................. 17

2.3.3

BatterySystemInfo() ('h04) .......................................................................................................................................................... 18

2.3.4

LTC() ('h3c) ................................................................................................................................................................................. 19

2.3.5

BatteryMode() ('h03) ................................................................................................................................................................... 19

2.3.6

Voltage() ('h09) ........................................................................................................................................................................... 19

2.3.7

Current() ('h0a) ............................................................................................................................................................................ 20

2.3.8

ChargingCurrent() ('h14) ............................................................................................................................................................. 20

2.3.9

ChargingVoltage() ('h15) ............................................................................................................................................................. 20

2.3.10

AlarmWarning() ('h16) ................................................................................................................................................................ 20

2.3.11

AlertResponse() ........................................................................................................................................................................... 21

2.4

SMBus Dual Port Operation ............................................................................................................................................................. 21

2.5

LTC1760 SMBus Controller Operation ............................................................................................................................................. 22

2.6

LTC1760 SMBALERT Operation ...................................................................................................................................................... 24

3

Charging Algorithm Overview .............................................................................................................................................................. 24

3.1

Wake-Up Charging Initiation ............................................................................................................................................................ 24

3.2

Wake-Up Charging Termination ....................................................................................................................................................... 24

3.3

Wake-Up Charging Current and Voltage Limits ............................................................................................................................... 25

3.4

Controlled Charging Initiation .......................................................................................................................................................... 25

3.5

Controlled Charging Termination ..................................................................................................................................................... 25

3.6

Controlled Charging Current and Voltage Programming .................................................................................................................. 26

4

System Power Management Algorithm and Battery Calibration .......................................................................................................... 27

4.1

Turning Off System Power ............................................................................................................................................................... 27

4.2

Power-By Algorithm When No Battery is Being Calibrated .............................................................................................................. 27

4.3

Power-By Algorithm When a Battery is Being Calibrated ................................................................................................................. 27

4.4

Power-By Reporting ........................................................................................................................................................................ 27

5

Battery Calibration (Conditioning) ....................................................................................................................................................... 28

5.1

Selecting a Battery to be Calibrated ................................................................................................................................................. 28

5.2

Initiating Calibration of Selected Battery .......................................................................................................................................... 28

5.3

Terminating Calibration of Selected Battery ..................................................................................................................................... 28

6

MODE Pin Operation ............................................................................................................................................................................ 29

6.1

Stand Alone Charge Indication ......................................................................................................................................................... 29

6.2

Hardware Charge Inhibit .................................................................................................................................................................. 29

6.3

Charging When SCL and SDA are Low ............................................................................................................................................ 29

6.4

Charging With an SMBus Host ........................................................................................................................................................ 29

7

Battery Charger Controller ................................................................................................................................................................... 29

7.1

Charge MUX Switches ..................................................................................................................................................................... 30

7.2

Dual Charging .................................................................................................................................................................................. 30

8

PowerPath Controller .......................................................................................................................................................................... 31

8.1

Autonomous PowerPath Switching ................................................................................................................................................. 31

8.2

Short-Circuit Protection ................................................................................................................................................................... 31

8.3

Emergency Turn-Off ........................................................................................................................................................................ 32

8.4

Power-Up Strategy .......................................................................................................................................................................... 32

9

The Voltage DAC Block ........................................................................................................................................................................ 32

10

The Current DAC Block ........................................................................................................................................................................ 32