LT6108-1/LT6108-2
High Side Current Sense
Amplifier with Reference
and Comparator
FEATURES DESCRIPTION
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Current Sense Amplifier
The LT 6108 is a complete high side current sense device
Fast Step Response: 500ns
that incorporates a precision current sense amplifier, an
Low Offset Voltage: 125V Maximum
integrated voltage reference and a comparator. Two ver-
Low Gain Error: 0.2% Maximum
sions of the LT6108 are available. The LT6108-1 has a
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Internal 400mV Precision Reference
latching comparator and the LT6108-2 has a non-latching
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Internal Comparator
comparator. In addition, the current sense amplifier and
Fast Response Time: 500ns
comparator inputs and outputs are directly accessible. The
Total Threshold Error: 1.25% Maximum
amplifier gain and comparator trip point are configured
Latching or Non-Latching Comparator Option
by external resistors. The open-drain comparator output
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Wide Supply Range: 2.7V to 60V
allows for easy interface to other system components.
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Supply Current: 450A
The overall propagation delay of the LT6108 is typically only
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Low Shutdown Current: 5A Maximum
1.4s, allowing for quick reaction to overcurrent condi-
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Specified for 40C to 125C Temperature Range
tions. The 1MHz bandwidth allows the LT6108 to be used
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Available in 8-Lead MSOP and 8-Lead (2mm 3mm)
for error detection in critical applications such as motor
DFN Packages
control. The high threshold accuracy of the comparator,
combined with the ability to latch the comparator, ensures
APPLICATIONS
the LT6108 can capture high speed events.
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Overcurrent and Fault Detection
The LT6108 is fully specified for operation from 40C to
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Current Shunt Measurement
125C, making it suitable for industrial and automotive
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Battery Monitoring
applications. The LT6108 is available in the small 8-lead
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Motor Control
MSOP and 8-lead DFN packages.
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Automotive Monitoring and Control
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L, LT, LTC, LTM, TimerBlox, Linear Technology and the Linear logo are registered trademarks
Remote Sensing
of Linear Technology Corporation. All other trademarks are the property of their respective
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Industrial Control
owners.
TYPICAL APPLICATION
Response to Overcurrent Event
Circuit Fault Protection with Very Fast Latching Load Disconnect
0.1
IRF9640
12V TO LOAD
V
LOAD
0.1F
1k 100
6.2V* 10V/DIV
SENSEHI SENSELO 0V
+
V OUTA V
OUT
I
3.3V
LT6108-1 LOAD
200mA/DIV
RESET EN/RST 6.04k
1k
10k
0mA
250mA DISCONNECT
V
OUTC
250mA DISCONNECT
2N2700
OUTC INC
5V/DIV
0V
V
1.6k
610812 TA01a
610812 TA01b
5s/DIV
*CMH25234B
610812fa
1LT6108-1/LT6108-2
ABSOLUTE MAXIMUM RATINGS (Note 1)
+
Total Supply Voltage (V to V ) .................................60V Amplifier Output Short-Circuit Duration (to V ) .. Indenfi ite
Maximum Voltage Operating Temperature Range (Note 3)
+
(SENSELO, SENSEHI, OUTA) ............................... V + 1V LT6108I ................................................40C to 85C
+
Maximum V (SENSELO or SENSEHI) ....................33V LT6108H ............................................ 40C to 125C
Maximum EN, EN/RST Voltage .................................60V Specified Temperature Range (Note 3)
Maximum Comparator Input Voltage ........................60V LT6108I ................................................40C to 85C
Maximum Comparator Output Voltage......................60V LT6108H ............................................ 40C to 125C
Input Current (Note 2) ..........................................10mA Maximum Junction Temperature .......................... 150C
SENSEHI, SENSELO Input Current ....................... 10mA Storage Temperature Range .................. 65C to 150C
Differential SENSEHI or SENSELO Input Current ..2.5mA MSOP Lead Temperature (Soldering, 10 sec) ........300C
PIN CONFIGURATION
LT6108-1 LT6108-2
TOP VIEW TOP VIEW
SENSELO 1 8 SENSEHI SENSELO 1 8 SENSEHI
+ +
EN/RST 2 7 V EN 2 7 V
6 OUTA 6 OUTA
OUTC 3 OUTC 3
V 4 5 INC V 4 5 INC
MS8 PACKAGE MS8 PACKAGE
8-LEAD PLASTIC MSOP 8-LEAD PLASTIC MSOP
= 163C/W, = 45C/W = 163C/W, = 45C/W
JA JC JA JC
TOP VIEW TOP VIEW
SENSELO 1 8 SENSEHI SENSELO 1 8 SENSEHI
+ +
EN/RST 2 7 V EN 2 7 V
9 9
OUTC 3 6 OUTA OUTC 3 6 OUTA
5 5
V 4 INC V 4 INC
DCB PACKAGE DCB PACKAGE
8-LEAD (2mm 3mm) PLASTIC DFN 8-LEAD (2mm 3mm) PLASTIC DFN
= 64C/W, = 10C/W = 64C/W, = 10C/W
JA JC JA JC
EXPOSED PAD (PIN 9) IS V , PCB CONNECTION OPTIONAL EXPOSED PAD (PIN 9) IS V , PCB CONNECTION OPTIONAL
610812fa
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