Linear Technology LTC2945: Wide Range I2C Power Monitor (requires DC590) DC1697A DC1697A 数据表
产品代码
DC1697A
LTC2945
1
2945fa
Typical applicaTion
FeaTures
DescripTion
Wide Range
I
2
C Power Monitor
Wide Range Power Monitor with Onboard ADC and I
2
C
applicaTions
n
Rail-to-Rail Input Range: 0V to 80V
n
Wide Input Supply Range: 2.7V to 80V
n
Shunt Regulator for Supplies >80V
n
Δ∑ ADC with less than ±0.75% Total Unadjusted Error
n
12-Bit Resolution for Current and Voltages
n
Internal Multiplier Calculates 24-Bit Power Value
n
Stores Minimum and Maximum Values
n
Alerts When Limits Exceeded
n
Additional ADC Input Monitors an External Voltage
n
Continuous Scan and Snapshot Modes
n
Shutdown Mode with I
Q
< 80µA
n
Split SDA for Opto-Isolation
n
Available in 12-Lead 3mm
× 3mm QFN and MSOP
Packages
n
Telecom Infrastructure
n
Industrial
n
Automotive
n
Consumer
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.
I
2
C
INTERFACE
NINE I
2
C
ADDRESSES
SENSE
+
SENSE
–
ALERT
SCL
SDAI
SDAO
ADIN
V
DD
INTV
CC
ADR1
ADR0
GND
LTC2945
MEASURED
VOLTAGE
TO
LOAD
0.1µF
0.02Ω
V
IN
4V TO 80V
2945 TA01
ADC Differential
Nonlinearity (ADIN)
ADC Integral Nonlinearity
(ADIN)
The
sures 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 program-
mable thresholds minimizes the need for software polling.
Data is reported via a standard I
2
C interface. Shutdown
mode reduces power consumption to 20µA.
The LTC2945 I
The LTC2945 I
2
C interface includes separate data input
and output pins for use with standard or opto-isolated I
2
C
connections. The LTC2945-1 has an inverted data output
for use with inverting opto-isolator configurations.
CODE
0
–0.3
ADC DNL (LSB)
0.3
0.0
0.1
0.2
–0.2
–0.1
3072
4096
1024
2048
2945 TA01a
CODE
0
–0.3
ADC INL (LSB)
0.3
0.0
0.1
0.2
–0.2
–0.1
3072
4096
1024
2048
2945 TA01b