FEATURES
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LTC2910
Octal Positive/Negative
Voltage Monitor
DESCRIPTION
The LTC
®
2910 is an octal input voltage monitor intended
for monitoring multiple voltages in a variety of applica-
tions. Each input has a nominal 0.5V threshold, featuring
1.5% tight threshold accuracy over the entire operating
temperature range. Glitch filtering ensures reliable reset
operation without false or noisy triggering.
Polarity selection and a buffered reference allow monitor-
ing up to two separate negative voltages. A three state
input pin allows setting the polarity of two inputs without
requiring any external components.
The LTC2910 provides a precise, versatile, space-con-
scious, micropower solution for voltage monitoring.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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8 Low Voltage Adjustable Inputs (0.5V)
Guaranteed Threshold Accuracy: ±1.5%
Input Glitch Rejection
Pin Selectable Input Polarity Allows
Negative and OV Monitoring
Buffered 1V Reference Output
Adjustable Reset Timeout with Timeout Disable
50μA Quiescent Current
Open Drain RST and
RST
Outputs
Guaranteed RST and
RST
for V
CC
≥ 1V
Available in 16-Lead SSOP and 16-Lead
(5mm × 3mm) DFN Packages
APPLICATIONS
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Desktop and Notebook Computers
Network Servers
Core, I/O Voltage Monitors
TYPICAL APPLICATION
Octal Supply Monitor, 10% Tolerance, 12V, 5V (x2), 3.3V (x2), 2.5V, 1.8V, 1.2V
12V
5V
TYPICAL TRANSIENT DURATION (μs)
3.3V
2.5V
POWER
SUPPLIES 1.8V
1.2V
5V
3.3V
54.9k
11k
11k
88.7k
11k
12.7k
11k
24.9k
11k
39.2k
11k
54.9k
11k
88.7k
11k
226k
SYSTEM
700
600
500
400
300
200
V
CC
= 6V
100
V
CC
= 2.3V
Typical Transient Duration
vs Comparator Overdrive
RESET OCCURS
ABOVE CURVE
V8
V7
V6
V5
V4
V3
V2
V1
V
CC
0.1μF
0
1
10
100
0.1
COMPARATOR OVERDRIVE PAST THRESHOLD (%)
2910 TA01b
LTC2910
GND
TMR
1nF
TIMEOUT = 8.5ms
DIS
RST
RST
SEL
2910 TA01
2910fc
1
LTC2910
ABSOLUTE MAXIMUM RATINGS
(Note 1, 2)
Terminal Voltages
V
CC
(Note 3)............................................. –0.3V to 6V
RST,
RST
................................................ –0.3V to 16V
TMR ..........................................–0.3V to (V
CC
+ 0.3V)
Vn, DIS, SEL ......................................... –0.3V to 7.5V
Terminal Current
I
VCC
....................................................................10mA
Reference Load Current (I
REF
) ...........................±1mA
I
RST/RST
..............................................................10mA
Operating Temperature Range
LTC2910C ................................................ 0°C to 70°C
LTC2910I.............................................. –40°C to 85°C
LTC2910H .......................................... –40°C to 125°C
Storage Temperature Range
SSOP DFN.......................................... –65°C to 150°C
,
Lead Temperature (Soldering, 10 sec)
SSOP ................................................................ 300°C
PACKAGE/ORDER INFORMATION
TOP VIEW
V1
V2
V3
V4
V5
V6
V7
V8
1
2
3
4
5
6
7
8
17
16 V
CC
15 TMR
14 SEL
13 DIS
12 RST
11 RST
10 REF
9
GND
V1
V2
V3
V4
V5
V6
V7
V8
1
2
3
4
5
6
7
8
TOP VIEW
16 V
CC
15 TMR
14 SEL
13 DIS
12 RST
11 RST
10 REF
9
GND
DHC16 PACKAGE
16-LEAD (5mm × 3mm) PLASTIC DFN
T
JMAX
= 150°C,
θ
JA
= 43.5°C/W
EXPOSED PAD (PIN 17) PCB GND CONNECTION OPTIONAL
GN16 PACKAGE
16-LEAD PLASTIC SSOP
T
JMAX
= 150°C,
θ
JA
= 110°C/W
ORDER PART NUMBER
LTC2910CDHC
LTC2910IDHC
LTC2910HDHC
DHC16 PART MARKING*
2910
2910
2910
ORDER PART NUMBER
LTC2910CGN
LTC2910IGN
LTC2910HGN
GN16 PART MARKING*
2910
2910I
2910H
Order Options
Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking:
http://www.linear.com/leadfree/
*The temperature grade is identified by a label on the shipping container.
ELECTRICAL CHARACTERISTICS
SYMBOL
V
SHUNT
ΔV
SHUNT
V
CC
PARAMETER
V
CC
Shunt Regulator Voltage
V
CC
Shunt Regulator Load Regulation
Supply Voltage
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 3.3V, Vn = 0.55V, SEL = V
CC
, DIS = OPEN unless otherwise noted.
(Note 2)
CONDITIONS
I
CC
= 5mA
–40°C < T
A
<125°C
I
CC
= 2mA to 10mA
●
●
●
●
MIN
6.2
6.2
2.3
TYP
6.6
6.6
200
MAX
6.9
7.0
300
V
SHUNT
UNITS
V
V
mV
V
2910fc
2
LTC2910
ELECTRICAL CHARACTERISTICS
SYMBOL
V
CC(MIN)
V
CC(UVLO)
ΔV
CC(UVHYST)
I
CC
V
REF
V
RT
t
PROP
I
VN
t
RST
V
DIS(VIH)
V
DIS(VIL)
I
DIS
I
TMR(UP)
I
TMR(DOWN)
V
TMR(DIS)
V
OH
V
OL
PARAMETER
Minimum V
CC
Output Valid
Supply Undervoltage Lockout
Supply Current
Reference Output Voltage
Vn Input Voltage Threshold
Vn Input Threshold to Output Delay
Vn Input Current
–40°C < T
A
< 125°C
Reset Timeout Period
DIS Input Threshold Voltage High
DIS Input Threshold Voltage Low
DIS Input Current
TMR Pull-Up Current
TMR Pull-Down Current
Timer Disable Voltage
Output Voltage High RST/RST
Output Voltage Low RST/RST
V
DIS
> 0.5V
V
TMR
= 0V
–40°C < T
A
< 125°C
V
TMR
= 1.6V
–40°C < T
A
< 125°C
Referenced to V
CC
V
CC
= 2.3V, I
RST/RST
= –1μA
V
CC
= 2.3V, I
RST/RST
= 2.5mA
V
CC
= 1V, I
RST
= 100μA
C
TMR
= 1nF
–40°C < T
A
< 125°C
V
n
= V
RT
– 5mV
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 3.3V, Vn = 0.55V, SEL = V
CC
, DIS = OPEN unless otherwise noted.
(Note 2)
CONDITIONS
DIS = 0V
V
CC
Rising, DIS = 0V
V
CC
= 2.3V to 6V
I
VREF
= ±1mA
–40°C < T
A
< 125°C
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
MIN
1.9
5
0.985
0.985
492
50
TYP
2
25
50
1
1
500
125
MAX
1
2.1
50
100
1.015
1.020
508
500
±15
±30
UNITS
V
V
mV
μA
V
V
mV
μs
nA
nA
ms
ms
V
V
μA
μA
μA
μA
μA
mV
V
Supply Undervoltage Lockout Hysteresis DIS = 0V
6
6
1.2
8.5
8.5
12.5
14
0.8
1
–1.3
–1.2
1.3
1.2
–180
1
2
–2.1
–2.1
2.1
2.1
–270
0.1
0.01
3
–2.8
–2.8
2.8
2.8
0.3
0.15
0.4
V
V
V
V
V
V
μA
μA
Three-State Input SEL
V
IL
V
IH
V
Z
I
SEL
I
SEL(MAX)
Low Level Input Voltage
High Level Input Voltage
Pin Voltage when Left in Hi-Z State
SEL High, Low Input Current
Maximum SEL Input Current
SEL tied to either V
CC
or GND
I
SEL
= ±10μA
–40°C < T
A
< 125°C
●
●
●
●
●
●
1.4
0.6
0.6
0.9
0.9
1.1
1.2
±25
±30
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
All currents into pins are positive; all voltages are referenced to
GND unless otherwise noted.
Note 3:
V
CC
maximum pin voltage is limited by input current. Since the
V
CC
pin has an internal 6.5V shunt regulator, a low impedance supply that
exceeds 6V may exceed the rated terminal current. Operation from higher
voltage supplies requires a series dropping resistor. See Applications
Information.
2910fc
3
LTC2910
TIMING DIAGRAM
Vn Positive Monitor Timing
Vn
V
RT
t
PROP
RST
1V
t
RST
RST
1V
2910 TD01
Vn Positive Monitor Timing (TMR strapped to V
CC
)
Vn
V
RT
t
PROP
RST
1V
t
PROP
RST
1V
2910 TD03
Vn Negative Monitor Timing
Vn
V
RT
t
PROP
RST
1V
t
RST
RST
1V
2910 TD02
Vn Negative Monitor Timing (TMR strapped to V
CC
)
Vn
V
RT
t
PROP
RST
1V
t
PROP
RST
1V
2910 TD04
2910fc
4
LTC2910
TYPICAL PERFORMANCE CHARACTERISTICS
unless otherwise noted. (Note 2)
Input Threshold Voltage vs
Temperature
0.505
0.504
THRESHOLD VOLTAGE, V
RT
(V)
0.503
0.502
I
CC
(μA)
0.501
0.500
0.499
0.498
0.497
0.496
0.495
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
2910 G01
Specifications are at T
A
= 25°C and V
CC
= 3.3V
V
CC
Shunt Voltage vs
Temperature
6.8
6.7
10mA
Supply Current vs Temperature
65
60
V
CC
= 5V
55
50
45
40
35
–50
V
CC
= 2.3V
V
CC
= 3.3V
V
CC
(V)
6.6
6.5
6.4
6.3
5mA
2mA
1mA
200μA
–25
25
50
0
TEMPERATURE (°C)
75
100
2910 G02
6.2
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
2910 G03
V
CC
Shunt Voltage vs I
CC
6.75
REFERENCE VOLTAGE, V
REF
(V)
1.005
1.004
6.65
1.003
1.002
1.001
1.000
0.999
0.998
0.997
0.996
6.25
–2
0
2
6
4
I
CC
(mA)
8
10
12
Buffered Reference Voltage vs
Temperature
700
TYPICAL TRANSIENT DURATION (μs)
600
500
400
300
200
Transient Duration vs Comparator
Overdrive
V
CC
(V)
6.55
25°C
–40°C
85°C
6.35
RESET OCCURS
ABOVE CURVE
6.45
V
CC
= 6V
100
V
CC
= 2.3V
0.995
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
2910 G05
0
0.1
1
10
100
COMPARATOR OVERDRIVE PAST THRESHOLD (%)
2910 G06
2910 G04
Reset Time-Out Period vs
Temperature
12
RST/RST TIMEOUT PERIOD, t
RST
(ms)
11
0.6
RST
VOLTAGE (V)
10
9
8
7
6
–50
0
–25
0
25
50
TEMPERATURE (°C)
75
100
2910 G07
RST
Output Voltage vs V
CC
0.8
V
CC
4
RST
VOLTAGE (V)
1.0
2910 G08
RST
Output Voltage vs V
CC
5
Vn = 0.55V
SEL = V
CC
C
TMR
= 1nF
3
0.4
RST
WITH
10k PULL-UP
0.2
RST
WITHOUT
10k PULL-UP
0
0.8
0.2
0.4
0.6
SUPPLY VOLTAGE, V
CC
(V)
2
1
0
0
1
2
3
4
SUPPLY VOLTAGE, V
CC
(V)
5
2910 G09
2910fc
5