FEATURES

Rail-to-Rail Input Range: 0V to 80V

Wide Input Supply Range: 2.7V to 80V

Shunt Regulator for Supplies >80V

ΔΣ ADC with less than ±0.75% Total Unadjusted Error

12-Bit Resolution for Current and Voltages

Internal Multiplier Calculates 24-Bit Power Value

Stores Minimum and Maximum Values

Alerts When Limits Exceeded

Additional ADC Input Monitors an External Voltage

Continuous Scan and Snapshot Modes

Shutdown Mode with IQ < 80μA

Split SDA for Opto-Isolation

Available in 12-Lead 3mm × 3mm QFN and

MSOP Packages

AEC-Q100 Qualified for Automotive Applications

APPLICATIONS

Telecom Infrastructure

Industrial

Automotive

Consumer

DESCRIPTION

The LTC?2945 is a rail-to-rail system monitor that measures

current, voltage, and power. It features an operating

range of 2.7V to 80V and includes a shunt regulator for

supplies above 80V to allow flexibility in the selection

of input supply. The current measurement range of 0V

to 80V is independent of the input supply. An onboard

0.75% accurate 12-bit ADC measures load current, input

voltage and an auxiliary external voltage. A 24-bit power

value is generated by digitally multiplying the measured

12-bit load current and input voltage data. Minimum and

maximum values are stored and an overrange alert with

programmable thresholds minimizes the need for software

polling. Data is reported via a standard I2C interface.

Shutdown mode reduces power consumption to 20μA.

The LTC2945 I2C interface includes separate data input

and output pins for use with standard or opto-isolated I2C

connections. The LTC2945-1 has an inverted data output

for use with inverting opto-isolator configurations.