LTC1760CFW Linear Technology, LTC1760CFW Datasheet

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... Smart Batteries without generating partial messages to batteries or SMBus Host. Thermistors on both batteries are automatically monitored for tempera- ture and disconnection information (SafetySignal). , LTC and LT are registered trademarks of Linear Technology Corporation. PowerPath is a trademark of Linear Technology Corporation. Protected by U.S. Patents, including *5723970 **6650174 3500 ...

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... VCC Ramping Down, Measured GND PLUS PLUS I = 0mA to 10mA VCC With Respect to Voltage Reported by Battery V < Requested Voltage < V CHMIN LIMIT U W ORDER PART TOP VIEW NUMBER 48 SCH2 47 GCH2 46 GCH1 LTC1760CFW 45 SCH1 44 TGATE 43 BOOST DCIN BGATE 38 PGND 37 COMP1 36 CLP 35 CSP 34 ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T unless otherwise noted. SYMBOL PARAMETER I Current Accuracy TOL f Regulator Switching Frequency 0SC f Regulator Switching Frequency in Low DO Dropout Mode DC Regulator Maximum Duty Cycle MAX I Maximum ...

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LTC1760 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T unless otherwise noted. SYMBOL PARAMETER V V Granularity STEP DAC V Charging Voltage Limit LIMIT (Note 7) Charge Mux Switches t GCH1/GCH2 Turn-On Time ONC t GCH1/GCH2 Turn-Off Time OFFC ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T unless otherwise noted. SYMBOL PARAMETER t Gate B1I/B2I/DCI Turn-On Time ONPI t Gate B1I/B2I/DCI Turn-Off Time OFFPI V Input Gate Clamp Voltage PONI GB1I GB2I GDCI V Input Gate Off Voltage ...

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LTC1760 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T unless otherwise noted. SYMBOL PARAMETER SCL/SCL1/SCL2/SDA/SDA1/ SDA2/ SMBALERT Power Down Leakage SMBALERT Output Low Voltage (V SMBALERT Output Pull-Up Current V V Input Low Voltage (V ) IL_VDDS DDS IL ...

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ELECTRICAL CHARACTERISTICS Note 10. Does not include current supplied VCC2_AC0 Note 11. Measured with thermistors not present, R removed and SMBALERT = 1. See Applications Information section: “Calculating IC Operating Current” for example on how to ...

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LTC1760 W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Charging Current 100 0.025 0.10 0.50 2.5 4.0 I (A) OUT 1760 G07 Power Path Switching 1 and 2 ...

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CTIO S GB2O (Pin 10): BAT2 Output Switch Gate Drive. Together with GB2I, this pin drives the gate of the P-channel switch in series with the BAT2 input switch. GB2I (Pin 11): BAT2 Input Switch ...

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LTC1760 CTIO S DCDIV (Pin 16): DCDIV Comparator Input from External Resistor Divider Connected from DCIN to GND. If the voltage at DCDIV pin is above the DCDIV comparator threshold, then the AC_PRESENT bit is ...

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W BLOCK DIAGRA CHARGE DCIN PUMP ON GCH1 – SCH1 45 ON GCH2 – CSN SCH2 48 BAT1 3 2 BAT2 V 1 SCN PLUS V 25 CC2 REGULATOR 24 GND ...

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LTC1760 U U TABLE 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 ...

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U OPERATIO (Refer to Block Diagram and Typical Application Figure) 1 Overview The LTC1760 is composed of an SMBus interface with dual port capability, a sequencer for managing system power and the charging and discharging of two batteries, a battery ...

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LTC1760 U OPERATIO 2.2 Data Bit Definition of Supported SMBus Functions. LTC1760 SMBus Function Mode Access BatterySystemState() Slave Read/ Write BatterySystemStateCont() Slave Read/ Write BatterySystemInfo() Slave Read LTC() Slave Read/ Write BatteryMode() Master Read 14 SMBus Command Data Address Code ...

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U OPERATIO LTC1760 Function Mode Access Current() Master Read Voltage() Master Read ChargingCurrent() Master Read ChargingVoltage() Master Read AlarmWarning () Master Read AlertResponse () Slave Read see (1) Byte (1) Read-byte format. 'h14 is returned as the interrupt address of ...

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LTC1760 U OPERATIO 2.3 Description of Supported SMBus Functions The functions are described as follows: Function Name() (command code) Description: A brief description of the function. Purpose: The purpose of the function, and an example where appropriate. SMBus Protocol: Refer ...

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U OPERATIO CHARGE_BAT[4:1] The read only CHARGE_BAT[4:1] nibble is used by the SMBus Host to determine which, if any, battery is being charged. All writes to this nibble will be ignored. Allowed values are: 'b0011: Battery 2 and Battery 1 ...

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LTC1760 U OPERATIO CALIBRATE_REQUEST Bit The read only CALIBRATE_REQUEST bit is set whenever the LTC1760 has determined that one or more of the connected batteries need a calibration cycle. Allowed values are: 'b1: The LTC1760 has determined that one or ...

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U OPERATIO BATTERY_SYSTEM_REVISION Nibble The read only BATTERY_SYSTEM_REVISION nibble re- ports the version of the Smart Battery System Manager specification supported. LTC1760 returns 'b1000 for this nibble, indicating Version 1.0 without optional PEC support. 2.3.4 LTC() ('h3c) Description: This function ...

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LTC1760 U OPERATIO 2.3.7 Current() ('h0a) Description: This function is used by the LTC1760 to read the actual current being supplied through the battery terminals. Purpose: Allows the LTC1760 to determine how much current a battery is receiving through its ...

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U OPERATIO TERMINATE_CHARGE_RESERVED Bit The read only TERMINATE_CHARGE_RESERVED bit is used by the LTC1760 to determine if charging may con- tinue. Allowed values are: 'b1: The LTC1760 will not charge this battery. 'b0: The LTC1760 may charge this battery if ...

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LTC1760 U OPERATIO SMB* HOST LTC1760 SMBus CONTROLLER HOST, LTC1760 AND BAT1 CAN COMMUNICATE. BAT2 ORIGINATED COMMANDS ARE IGNORED. (1a) SMB* HOST LTC1760 SMBus CONTROLLER HOST, LTC1760 AND BAT2 CAN COMMUNICATE. BAT1 ORIGINATED COMMANDS ARE IGNORED. (1c) *SMB INCLUDES SCL ...

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U OPERATIO LTC1760 1760f 23 ...

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LTC1760 U OPERATIO 2.6 LTC1760 SMBALERT Operation The SMBALERT pin allows the LTC1760 to signal to the SMBus Host that there has been a change of status. This pin is asserted low whenever there is a change in battery presence, ...

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U OPERATIO 6. An SMBus Host write asserts the LTC1760 BatterySystemStateCont(CHARGING_INHIBIT) high. 7. Hardware controlled charging inhibit is asserted (MODE low with V high). DDS 8. The thermistor of the battery being charged indicates COLD-RANGE and the battery has been ...

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LTC1760 U OPERATIO This bit will remain set if a subsequent AlarmWarning() fails to respond. The cached alarm will be cleared by any of the following conditions. a) Associated battery is removed subsequent AlarmWarning() clears all charge alarm ...

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U OPERATIO 4 System Power Management Algorithm and Battery Calibration 4.1 Turning Off System Power The LTC1760 allows the user to turn off system power using the LTC(POWER_OFF) bit. When POWER_OFF is asserted high all power management functions are by- ...

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LTC1760 U OPERATIO 5 Battery Calibration (Conditioning) Calibration allows the SMBus Host to fully discharge a battery for conditioning purposes. The SMBus Host may determine the battery to be discharged or allow the LTC1760 to choose based on the batteries’ ...

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U OPERATIO 6 MODE Pin Operation The MODE pin is a multifunction pin that allows the LTC1760 to: 1) display charging status in stand alone operation; 2) activate hardware charge inhibit; 3) charge when SCL and SDA are low and; ...

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LTC1760 U OPERATIO OFF TGATE ON t OFF ON BGATE OFF INDUCTOR CURRENT Figure 4. at hand. The average current control loop converts the voltage between CSP and BAT to a representative current. Error amp CA2 compares this current against ...

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U OPERATIO 8 PowerPath Controller The PowerPath switches are turned on and off by the power management algorithm. The external PFETs are usually connected as an input switch and an output switch. The output switch PFET is connected in series ...

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LTC1760 U OPERATIO V and 2µ including tolerances) should keep PLUS CC the LTC1760 operating above the UVLO trip voltage long enough to perform the short-circuit function when the input voltages are greater than 8V. Increasing the ...

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U U APPLICATIO S I FOR ATIO Automatic Current Sharing In a dual parallel charge configuration, the LTC1760 does not actually control the current flowing into each individual battery. The capacity, or Amp-Hour rating, of each battery determines how the ...

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... Extending System to More than 2 Batteries The LTC1760 can be extended to manage systems with more than 3 sources of power. Contact Linear Technology Applications Engineering for more information. Charge Termination Issues Batteries with constant-current charging and voltage- ...

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U U APPLICATIO S I FOR ATIO CA1. Remember the maximum ∆I mum input voltage. In practice 10µH is the lowest value recommended for use. Charger Switching Power MOSFET and Diode Selection Two external power MOSFETs must be selected for ...

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LTC1760 U U APPLICATIO S I FOR ATIO For thermistors that are IDEAL-RANGE 4/64 • V /(RXB + R SAFETYX VCC2 (R1A +R ) THX For thermistors that are HOT-RANGE 4/64 • V /(RXB + R ...

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U U APPLICATIO S I FOR ATIO Calculating IC Power Dissipation The power dissipation of the LTC1760 is dependent upon the gate charge of Q and Application). The gate charge is determined from the manufacturer’s data sheet ...

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LTC1760 U U APPLICATIO S I FOR ATIO The relatively high ESR of an aluminum electrolytic for C15, located at the AC adapter input terminal, is helpful in reducing ringing during the hot-plug event. Refer to AN88 for more information. ...

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U U APPLICATIO S I FOR ATIO C/10 or less which is well within the linear operation range of the MOSFETs. 3. Voltage tracking for the discharge process does not need such precise voltage tracking values. The LTC1760 has two ...

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LTC1760 U U APPLICATIO S I FOR ATIO A) Single Battery Configuration. To limit the LTC1760 to a single battery, modify the battery slot to be eliminated as follows: 1) Remove both FETs (Q5 Q7, Q8) involved in ...

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U U APPLICATIO S I FOR ATIO SWITCH NODE L1 HIGH FREQUENCY CIRCULATING PATH Figure 11. High-Speed Switching Path 4. Place the output current sense resistor right next to the inductor output but oriented such that ...

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LTC1760 U TYPICAL APPLICATIO 0.03Ω 0.1µF 4.99k 12.7k R5 1.21k C11 49.9k 46 1800pF C3 45 0.012µ DDS 24 SMBALERT ...

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... DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED .254mm (.010") PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...

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... AC Adapter Current Limit, SafetySignal Sensor and Indicator Outputs Constant Current/ Constant Voltage Switching Regulator; Resistor Voltage/Current Programming, AC Adapter Current Limit and SafetySignal Sensor SMBus Rev 1.1 Compliant www.linear.com ● for 5% Current Accuracy DAC 1760f LT/TP 1004 1K • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2003 ...