Datasheet

LTC2945
28
2945fa
For more information www.linear.com/LTC2945
Typical applicaTions
Power Monitoring in –48V System Using External Linear Regulator to Supply Opto-couplers and SCL/SDA Resistive Pull-Ups
Wide Range Dual Supply Monitor with Single LTC2945
V
CC
GND
C1
1µF
PS9817-2
CONTROL REGISTER A2 = 0
V
EE
PS9817-2
2945 TA07
ADR0
ADIN
ADR1
SCL
V
DD
INTV
CC
V
EE
SDAI
SDAO
ALERT
SENSE
–
GND
SENSE
+
LTC2945
LT3010-5
V
CC
GND
–48V
RTN
V
EE
–48V INPUT
R7
0.5k
R3
0.51k
R4
1k
V
OUT
R8
0.51k
R9
1k
R10
1k
R11
10k
5V
5V
R
SNS
0.02Ω
V
DD
GND
µP
SCL
SDA
INT
R1
1k
R2
10k
IN
SHDN
OUT
SENSE
GND
C3
0.1µF
C2
1µF
* SELECT RSHUNT ACCORDING TO THE EQUATION IN THE “FLEXIBLE POWER SUPPLY TO LTC2945” SECTION.
** VOLTAGE DATA HAS AN OFFSET VALUE DUE TO D1’S DROP, IF DESIRABLE THIS CAN BE COMPENSATED THROUGH SOFTWARE.
R
ADIN
20k
2945 TA08
R
SNS
0.02Ω
C3
0.1µF
C2
0.1µF
ADR0
ADR1
V
DD
INTV
CC
SDAI
SCL
SDAO
ALERT
ADIN
SENSE
+
GND
SENSE
–
LTC2945
LTC6102
R
IN2
1k
R
SHUNT*
D2
BAT54
D1
BAT54
R
IN1
1k
C1
0.1µF
R
SNS1
0.02Ω
V
+
V
–
V
REG
–INF –INS
OUT
+IN
SUPPLY B
4.5V TO 80V
SUPPLY A
4.5V TO 80V
I
2
C
INTERFACE
TO
LOAD
SUPPLY A SENSE
+
∆SENSE INTERNALLY GENERATED
USE EXTERNAL µP TO MULTIPLY VOLTAGE (V
DD
)
AND CURRENT (ADIN) DATA
ADINV
DD
**
1
VOLTAGE
DATA
CURRENT
DATA
POWER
DATA
CONTROL REG
A2
0SUPPLY B