LTC2908
1
2908fd
APPLICATIONS
n
Network Servers
n
Wireless Base Stations
n
Optical Networking Systems
n
Multivoltage Systems
n
Desktop and Notebook Computers
TYPICAL APPLICATION
DESCRIPTION
Precision
Six Input Supply Monitor
FEATURES
V1 (V)
0
RST OUTPUT VOLTAGE (V)
0.2
V2 = GND
0.3
0.8
2908 TA01b
0.1
0
0.2
0.4
0.6
0.4
V3 = V4 = V
ADJ1
=
V
ADJ2
= V
ADJ3
=
V
ADJ4
= V
ADJ5
= GND
V1 INPUT
V2 = V1 (A1/B1)
Six Supply Monitor with 5% Tolerance
(12V, 3.3V, 2.5V, 1.8V, 1.5V, 1.2V)
RST
2.15M
0.1μF
V1 V2 V3 V4
GND
LTC2908-B1
V
ADJ1
12V
3.3V
2.5V
1.8V
1.5V
1.2V
2908 TA01a
0.1μF
100k
DC/DC
DC/DC
DC/DC
DC/DC
DC/DC
SYSTEM
124k
V
ADJ2
100k
RST Output Voltage vs V1
with 10k Pull-Up Resistor to V1
The LTC
®
2908 is a six input supply monitor for systems
requiring a precise and compact monitoring solution
for multiple supply voltages. The inputs can be shorted
together for monitoring systems with fewer than six
supply voltages, and the open drain RST output of two or
more LTC2908s can be wired-OR together for monitoring
systems with more than six supply voltages. The common
reset output remains low until all six inputs have been in
compliance for 200ms.
The LTC2908 features a tight 1.5% threshold accuracy over
the entire operating temperature range and glitch immunity
to ensure reliable reset operation without false triggering.
The open-drain RS T output state is guaranteed to be in the
correct state as long as V1 and/or V2 is 0.5V or greater.
The LTC2908 also features adjustable inputs with a nominal
threshold level at 0.5V. This product provides a precise,
space-conscious, micropower and general purpose solu-
tion for any kind of system requiring supply monitors.
n
Ultralow Voltage Reset: V
CC
= 0.5V Guaranteed*
n
Monitors Six Inputs Simultaneously:
5V, 3.3V, 2.5V, 1.8V, ADJ1, ADJ2 (LTC2908-A1)
3.3V, 2.5V, 1.8V, 1.5V, ADJ1, ADJ2 (LTC2908-B1)
2.5V, ADJ1, ADJ2, ADJ3, ADJ4, ADJ5 (LTC2908-C1)
n
Guaranteed Threshold Accuracy: ±1.5% of
Monitored Voltage Overtemperature
n
Internal V
CC
Auto Select
n
Power Supply Glitch Immunity
n
200ms Reset Time Delay
n
Active Low Open-Drain RST Output
n
Low Profi le (1mm) 8-Lead SOT-23 (ThinSOT™) and
Plastic (3mm × 2mm) DFN Packages
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. All other
trademarks are the property of their respective owners. *Patent pending.
LTC2908
2
2908fd
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
Terminal Voltages
V1, V2, V3, V4 ......................................... 0.3V to 7V
V
ADJ1
, V
ADJ2
,
V
ADJ3
, ..................–0.3V to (V
CC
+ 0.6V)
V
ADJ4
,
V
ADJ5
.............................–0.3V to (V
CC
+ 0.6V)
RST .......................................................... –0.3V to 7V
Operating Temperature Range
LTC2908C ................................................ 0°C to 70°C
LTC2908I..............................................40°C to 85°C
(Notes 1, 2)
Storage Temperature Range
DFN Package ......................................65°C to 125°C
TSOT-23 Package ...............................65°C to 150°C
Lead Temperature (Soldering, 10 sec) .................. 300°C
LTC2908CDDB-A1
LTC2908IDDB-A1
LTC2908CDDB-B1
LTC2908IDDB-B1
TOP VIEW
9
DDB8 PACKAGE
8-LEAD (3mm × 2mm) PLASTIC DFN
5
6
7
8
4
3
2
1GND
RST
V4
V2
V
ADJ2
V3
V
ADJ1
V1
LTC2908CDDB-C1
LTC2908IDDB-C1
TOP VIEW
9
DDB8 PACKAGE
8-LEAD (3mm × 2mm) PLASTIC DFN
5
6
7
8
4
3
2
1GND
RST
V
ADJ5
V1
V
ADJ4
V
ADJ3
V
ADJ2
V
ADJ1
LTC2908CTS8-A1
LTC2908ITS8-A1
LTC2908CTS8-B1
LTC2908ITS8-B1
V2 1
V4 2
RST 3
GND 4
8V1
7 V
ADJ1
6V3
5 V
ADJ2
TOP VIEW
TS8 PACKAGE
8-LEAD PLASTIC TSOT-23
LTC2908CTS8-C1
LTC2908ITS8-C1
V1 1
V
ADJ5
2
RST 3
GND 4
8V
ADJ1
7 V
ADJ2
6V
ADJ3
5 V
ADJ4
TOP VIEW
TS8 PACKAGE
8-LEAD PLASTIC TSOT-23
T
JMAX
= 125°C, θ
JA
= 76°C/W
EXPOSED PAD (PIN 9)
(PCB CONNECTION OPTIONAL)
T
JMAX
= 125°C, θ
JA
= 76°C/W
EXPOSED PAD (PIN 9)
(PCB CONNECTION OPTIONAL)
T
JMAX
= 125°C, θ
JA
= 250°C/W T
JMAX
= 125°C, θ
JA
= 250°C/W
ORDER INFORMATION
Lead Free Finish
TAPE AND REEL (MINI) TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC2908CDDB-A1#TRMPBF LTC2908CDDB-A1#TRPBF LBFD
8-LEAD (3mm × 2mm) PLASTIC DFN
0°C to 70°C
LTC2908IDDB-A1#TRMPBF LTC2908IDDB-A1#TRPBF LBFF
8-LEAD (3mm × 2mm) PLASTIC DFN
40°C to 85°C
LTC2908CDDB-B1#TRMPBF LTC2908CDDB-B1#TRPBF LBFG
8-LEAD (3mm × 2mm) PLASTIC DFN
0°C to 70°C
LTC2908IDDB-B1#TRMPBF LTC2908IDDB-B1#TRPBF LBFH
8-LEAD (3mm × 2mm) PLASTIC DFN
40°C to 85°C
LTC2908CDDB-C1#TRMPBF LTC2908CDDB-C1#TRPBF LCFV
8-LEAD (3mm × 2mm) PLASTIC DFN
0°C to 70°C
LTC2908IDDB-C1#TRMPBF LTC2908IDDB-C1#TRPBF LCFV
8-LEAD (3mm × 2mm) PLASTIC DFN
40°C to 85°C
LTC2908CTS8-A1#TRMPBF LTC2908CTS8-A1#TRPBF LTBFJ 8-LEAD PLASTIC TSOT-23 0°C to 70°C
LTC2908ITS8-A1#TRMPBF LTC2908ITS8-A1#TRPBF LTBFK 8-LEAD PLASTIC TSOT-23 40°C to 85°C
LTC2908CTS8-B1#TRMPBF LTC2908CTS8-B1#TRPBF LTBFM 8-LEAD PLASTIC TSOT-23 0°C to 70°C
LTC2908ITS8-B1#TRMPBF LTC2908ITS8-B1#TRPBF LTBFN 8-LEAD PLASTIC TSOT-23 40°C to 85°C
LTC2908CTS8-C1#TRMPBF LTC2908CTS8-C1#TRPBF LTCFT 8-LEAD PLASTIC TSOT-23 0°C to 70°C
LTC2908ITS8-C1#TRMPBF LTC2908ITS8-C1#TRPBF LTCFT 8-LEAD PLASTIC TSOT-23 40°C to 85°C
TRM = 500 pieces. *Temperature grades are identifi ed by a label on the shipping container.
Consult LTC Marketing for parts specifi ed with wider operating temperature ranges.
Consult LTC Marketing for information on lead based fi nish parts.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifi cations, go to: http://www.linear.com/tapeandreel/
LTC2908
3
2908fd
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
RT50
5V, 5% Reset Threshold V1 Input Threshold
l
4.600 4.675 4.750 V
V
RT33
3.3V, 5% Reset Threshold V2 Input Threshold
l
3.036 3.086 3.135 V
V
RT25
2.5V, 5% Reset Threshold V3 Input Threshold
l
2.300 2.338 2.375 V
V
RT18
1.8V, 5% Reset Threshold V4 Input Threshold
l
1.656 1.683 1.710 V
V
RTADJ
ADJ, 5% Reset Threshold V
ADJ1
, V
ADJ2
Input Threshold
l
0.492 0.500 0.508 V
(LTC2908-A1) The l denotes specifi cations which apply over the full
operating temperature range, otherwise specifi cations are T
A
= 25°C, V
CC
= 5V unless otherwise noted. (Note 2)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
RT33
3.3V, 5% Reset Threshold V1 Input Threshold
l
3.036 3.086 3.135 V
V
RT25
2.5V, 5% Reset Threshold V2 Input Threshold
l
2.300 2.338 2.375 V
V
RT18
1.8V, 5% Reset Threshold V3 Input Threshold
l
1.656 1.683 1.720 V
V
RT15
1.5V, 5% Reset Threshold V4 Input Threshold
l
1.380 1.403 1.425 V
V
RTADJ
ADJ, 5% Reset Threshold V
ADJ1
, V
ADJ2
Input Threshold
l
0.492 0.500 0.508 V
(LTC2908-B1) The l denotes specifi cations which apply over the full operating temperature range, otherwise specifi cations are
T
A
= 25°C, V
CC
= 3.3V unless otherwise noted. (Note 2)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
RT25
2.5V, 5% Reset Threshold V1 Input Threshold
l
2.300 2.338 2.375 V
V
RTADJ
ADJ, 5% Reset Threshold V
ADJ1
, V
ADJ2
, V
ADJ3
, V
ADJ4
, V
ADJ5
,
Input Threshold
l
0.492 0.500 0.508 V
(LTC2908-C1) The l denotes specifi cations which apply over the full operating temperature range, otherwise specifi cations are
T
A
= 25°C, V
CC
= 2.5V unless otherwise noted. (Note 2)
The l denotes specifi cations which apply over the full operating temperature range, otherwise specifi cations are T
A
= 25°C. V
CC
= 5V
for the LT2908-A1, V
CC
= 3.3V for the LTC2908-B1or V
CC
= 2.5V for the LTC2908-C1, unless otherwise noted. (Notes 2, 3)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
CC
Internal Supply Voltage RST in Correct Logic State
l
0.5 6 V
I
V1
V1 Input Current (Note 4) V1 = 5.0V (LTC2908-A1)
V1 = 3.3V (LTC2908-B1)
V1 = 2.5V (LTC2908-C1)
l
l
l
26
24
22
70
70
70
μA
μA
μA
I
V2
V2 Input Current (Note 4) V2 = 3.3V (LTC2908-A1)
V2 = 2.5V (LTC2908-B1)
l
l
10
8
30
30
μA
μA
I
V3
V3 Input Current V3 = 2.5V (LTC2908-A1)
V3 = 1.8V (LTC2908-B1)
l
l
2
2
5
5
μA
μA
I
V4
V4 Input Current V4 = 1.8V (LTC2908-A1)
V4 = 1.5V (LTC2908-B1)
l
l
2
2
5
5
μA
μA
I
VADJ
V
ADJ1
, V
ADJ2,
V
ADJ3,
V
ADJ4,
V
ADJ5
Input Current
V
ADJ1
= V
ADJ2
= V
ADJ3
= V
ADJ4
= V
ADJ5
=
0.55V
l
±15 nA

LTC2908ITS8-C1#TRPBF

Mfr. #:
Manufacturer:
Analog Devices Inc.
Description:
Supervisory Circuits Six Supply Monitor in SOT-23
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
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