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.