LTC1760 ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the full operatingjunction temperature range, otherwise specifications are at TA = 25°C (Note 6). VDCIN = 20V, VBAT1 = 12V, VBAT2 = 12V, VVDDS = 3.3V,VVCC2 = 5.2V unless otherwise noted. SYMBOL PARAMETERCONDITIONSMINTYPMAXUNITS VIH_MODE MODE Input High Voltage (VIH) VVCC2 = 4.85V l VVCC2 • 0.7 V MODE Input Current (IIH) MODE = VVCC2 • 0.7V, VVCC2 = 4.85V l –1 1 µA MODE Input Current (IIL) MODE = VVCC2 • 0.3V, VVCC2 = 4.85V l –1 1 µA Charger Timing tTIMEOUT Timeout for Wake-Up Charging and l 140 175 210 sec Controlled Charging tQUERY Sampling Rate Used by the LTC1760 to 1 sec Update Charging Parameters SMBus Timing SCL Serial-Clock High Period(tHIGH) At IPULLUP = 350µA, CLOAD = 150pF (Note 8) l 4 µs SCL Serial-Clock Low Period (tLOW) At IPULLUP = 350µA, CLOAD = 150pF (Note 8) l 4.7 µs SDA/SCL Rise Time (tr) CLOAD = 150pF, RPU = 9.31k (Note 8) l 1000 ns SDA/SCL Fall Time (tf) CLOAD = 150pF, RPU = 9.31k (Note 8) l 300 ns SMBus Accelerator Trip Voltage Range l 0.8 1.42 V Start-Condition Setup Time (tSU:STA) l 4.7 µs Start-Condition Hold Time (tHD:STA) l 4 µs SDA to SCL Rising-Edge l 250 ns Setup Time (tSU:DAT) SDA to SCL Falling-Edge Hold Time, l 300 ns Slave Clocking in Data (tHD:DAT) tTIMEOUT_ The LTC1760 will Release the SMBus l 25 35 ms SMB and Terminate the Current Master or Slave Command if the Command is not Completed Before this Time Note 1: Stresses beyond those listed under Absolute Maximum Ratings lower than the terminal voltage. Refer to “Operation Section 3.7” for more may cause permanent damage to the device. Exposure to any Absolute information. Maximum Rating condition for extended periods may affect device Note 8: CLOAD is the combined capacitance on the host’s SMBus reliability and lifetime. connection and the selected battery’s SMBus connection. Note 2: Battery voltage must be adequate to drive gates of PowerPath Note 9: CLOAD_MAX is the maximum allowed combined capacitance on P-channel FET switches. This does not affect charging voltage of the THxA, THxB and the battery’s SafetySignalx connections. battery, which can be zero volts during wake-up charging. Note 10: Does not include current supplied by VCC to VCC2 (IVCC2_AC1 or Note 3: DCIN, BAT1, BAT2 are held at 12V and GDCI, GB1I, GB2I are IVCC2_AC0) forced to 10.5V. SCP is set at 12V to measure source current at GDCI, Note 11: Measured with thermistors not present, R GB1I and GB2I. SCP is set at 11.9V to measure sink current at GDCI, GB1I VLIMIT and RILIMIT removed and SMBALERT = 1. See Applications Information section: and GB2I. “Calculating IC Operating Current” for example on how to calculate total IC Note 4: Extrapolated from testing with CL = 50pF. operating current. Note 5: Accuracy dependent upon external sense resistor and Note 12: Requested currents below 44mV/RSENSE may not servo correctly compensation components. due to charger offsets. The charging current for requested currents below Note 6: The LTC1760 is tested under pulsed load conditions such that TJ ≈ 4mV/RSENSE will be between 4mV/RSENSE and (Requested Current – 8mA). TA. The LTC1760C is guaranteed to meet specifications from 0°C to 70°C Refer to Applications Information: “Setting Charger Output Current Limit” junction temperature. Specifications over the –40°C to 85°C operating for values of RSENSE. junction temperature range are assured by design, characterization and Note 13: This limit is greater than the absolute maximum for the charger. correlation with statistical process controls. The LTC1760I is guaranteed Therefore, there is no effective limitation for the voltage when this option over the –40°C to 125°C operating junction temperature range. is selected. Note 7: Charger servos to the value reported by a Voltage() query. This is Note 14: Does not apply to Wake-Up Mode. the internal cell voltage measured by the battery electronics and may be 1760fc For more information www.linear.com/LTC1760 7