LTC2945 Wide Range 2 I C Power Monitor FEATURES DESCRIPTION n Rail-to-Rail Input Range: 0V to 80V The LTC 2945 is a rail-to-rail system monitor that mea- n Wide Input Supply Range: 2.7V to 80V sures current, voltage, and power. It features an operating n Shunt Regulator for Supplies >80V range of 2.7V to 80V and includes a shunt regulator for n ADC with less than 0.75% Total Unadjusted Error supplies above 80V to allow flexibility in the selection of n 12-Bit Resolution for Current and Voltages input supply. The current measurement range of 0V to n Internal Multiplier Calculates 24-Bit Power Value 80V is independent of the input supply. An onboard 0.75% n Stores Minimum and Maximum Values accurate 12-bit ADC measures load current, input voltage n Alerts When Limits Exceeded and an auxiliary external voltage. A 24-bit power value is n Additional ADC Input Monitors an External Voltage generated by digitally multiplying the measured 12-bit load n Continuous Scan and Snapshot Modes current and input voltage data. Minimum and maximum n Shutdown Mode with I < 80A values are stored and an overrange alert with program- Q n Split SDA for Opto-Isolation mable thresholds minimizes the need for software polling. 2 n Available in 12-Lead 3mm 3mm QFN and MSOP Data is reported via a standard I C interface. Shutdown Packages mode reduces power consumption to 20A. 2 The LTC2945 I C interface includes separate data input APPLICATIONS 2 and output pins for use with standard or opto-isolated I C n connections. The LTC2945-1 has an inverted data output Telecom Infrastructure n for use with inverting opto-isolator configurations. Industrial n Automotive L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Consumer TYPICAL APPLICATION 2 Wide Range Power Monitor with Onboard ADC and I C ADC Differential ADC Integral Nonlinearity Nonlinearity (ADIN) (ADIN) 0.02 V TO IN 4V TO 80V LOAD 0.3 0.3 0.2 0.2 + SENSE SENSE V ALERT 0.1 0.1 DD LTC2945 INTV SCL CC 2 I C 0.1F 0.0 0.0 INTERFACE ADR1 SDAI 2 NINE I C 0.1 0.1 ADDRESSES ADR0 SDAO MEASURED ADIN VOLTAGE 0.2 0.2 GND 2945 TA01 0.3 0.3 0 1024 2048 3072 4096 0 1024 2048 3072 4096 CODE CODE 2945 TA01a 2945 TA01b 2945fb 1 For more information www.linear.com/LTC2945 ADC DNL (LSB) ADC INL (LSB)LTC2945 ABSOLUTE MAXIMUM RATINGS (Notes 1, 2) SCL, SDAI Voltages (Note 4) ..................... 0.3V to 5.9V V Voltage .............................................. 0.3V to 100V DD SCL, SDAI Clamp Current ........................................5mA + SENSE Voltage ...........................................1V to 100V Operating Temperature Range + + SENSE Voltage .....1V or SENSE 1V to SENSE + 1V LTC2945C ................................................ 0C to 70C INTV Voltage (Note 3) ........................... 0.3V to 5.9V CC LTC2945I .............................................40C to 85C ADR1, ADR0, ADIN, ALERT, SDAO, SDAO LTC2945H .......................................... 40C to 125C Voltage ......................................................... 0.3V to 7V Storage Temperature Range .................. 65C to 150C INTV Clamp Current ...........................................35mA CC Lead Temperature (Soldering, 10sec) MS Package Only ..............................................300C PIN CONFIGURATION LTC2945 TOP VIEW TOP VIEW 12 11 10 + V 1 12 SENSE DD 2 INTV 1 9 ALERT INTV 11 SENSE CC CC 3 ADR1 10 ALERT ADR1 2 13 8 SDAO 4 9 SDAO ADR0 ADR0 3 7 SDAI ADIN 5 8 SDAI GND 6 7 SCL 4 5 6 MS PACKAGE 12-LEAD PLASTIC MSOP T = 125C, q = 135C/W JMAX JA UD PACKAGE 3mm) PLASTIC QFN 12-LEAD (3mm T = 125C, q = 58.7C/W JMAX JA EXPOSED PAD (Pin 13) PCB GND CONNECTION OPTIONAL LTC2945-1 TOP VIEW TOP VIEW 12 11 10 + V 1 12 SENSE DD 2 INTV 1 9 ALERT INTV 11 SENSE CC CC 3 ADR1 10 ALERT ADR1 2 13 8 SDAO 4 9 SDAO ADR0 ADR0 3 7 SDAI ADIN 5 8 SDAI GND 6 7 SCL 4 5 6 MS PACKAGE 12-LEAD PLASTIC MSOP T = 125C, q = 135C/W JMAX JA UD PACKAGE 3mm) PLASTIC QFN 12-LEAD (3mm T = 125C, q = 58.7C/W JMAX JA EXPOSED PAD (Pin 13) PCB GND CONNECTION OPTIONAL 2945fb 2 For more information www.linear.com/LTC2945 ADIN V ADIN V DD DD + + GND SENSE GND SENSE SCL SENSE SCL SENSE