FEATURES
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LTC2914
Quad UV/OV
Positive/Negative
Voltage Monitor
DESCRIPTION
The LTC
®
2914 is a quad input voltage monitor intended for
monitoring multiple voltages in a variety of applications.
Dual inputs for each monitored voltage allow monitoring
four separate undervoltage (UV) conditions and four
separate overvoltage (OV) conditions. All monitors share a
common undervoltage output and a common overvoltage
output. The LTC2914-1 has latching capability for the
overvoltage output. The LTC2914-2 has functionality to
disable both the overvoltage and undervoltage outputs.
Polarity selection and a buffered reference allow monitoring
up to two separate negative voltages. A three-state input pin
allows setting the polarity of two inputs without requiring
any external components. Glitch filtering ensures reliable
reset operation without false or noisy triggering.
The LTC2914 provides a precise, versatile, space-con-
scious, micropower solution for voltage monitoring.
L,
LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Monitors Four Voltages Simultaneously
Adjustable UV and OV Trip Values
Guaranteed Threshold Accuracy: ±1.5% of
Monitored Voltage over Temperature
Input Glitch Rejection
Monitors up to Two Negative Voltages
Buffered 1V Reference Output
Adjustable Reset Timeout with Timeout Disable
62μA Quiescent Current
Open-Drain
OV
and
UV
Outputs
Guaranteed
OV
and
UV
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
Quad UV/OV Supply Monitor,10% Tolerance, 5V, 3.3V, 2.5V, 1.8V
P0WER
SUPPLIES
5V
3.3V
2.5V
1.8V
0.1μF
44.2k
VH1
1k
27.4k
VL1
VH2
4.53k
1k
4.53k
19.6k
VL2
REF
VH3
1k
12.4k
VL3
VH4
4.53k
1k
VL4
GND
4.53k
TMR
C
TMR
22nF
2914 TA01a
Input Threshold Voltage
vs Temperature
V
CC
THRESHOLD VOLTAGE, V
OUT
(V)
SEL
OV
SYSTEM
UV
LATCH
0.505
0.504
0.503
0.502
0.501
0.500
0.499
0.498
0.497
0.496
0.495
–50
–25
25
50
0
TEMPERATURE (°C)
75
100
LTC2914-1
2914 TA01b
TIMEOUT = 200ms
2914fa
1
LTC2914
ABSOLUTE MAXIMUM RATINGS
(Notes 1, 2)
Terminal Voltages
V
CC
(Note 3)............................................. –0.3V to 6V
OV, UV
................................................... –0.3V to 16V
TMR ..........................................–0.3V to (V
CC
+ 0.3V)
VLn, VHn,
LATCH,
DIS, SEL .................. –0.3V to 7.5V
Terminal Currents
I
VCC
....................................................................10mA
Reference Load Current (I
REF
) ...........................±1mA
I
UV
, I
OV
...............................................................10mA
Operating Temperature Range
LTC2914C ................................................ 0°C to 70°C
LTC2914I.............................................. –40°C to 85°C
LTC2914H .......................................... –40°C to 125°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
SSOP ................................................................ 300°C
PACKAGE/ORDER INFORMATION
TOP VIEW
TOP VIEW
VH1
VL1
VH2
VL2
VH3
VL3
VH4
VL4
1
2
3
4
5
6
7
8
17
16 V
CC
15 TMR
14 SEL
13
LATCH
12
UV
11
OV
10 REF
9
GND
VH1
VL1
VH2
VL2
VH3
VL3
VH4
VL4
DHC 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
1
2
3
4
5
6
7
8
16 V
CC
15 TMR
14 SEL
13
LATCH
12
UV
11
OV
10 REF
9
GND
ORDER PART
NUMBER
LTC2914CDHC-1
LTC2914IDHC-1
LTC2914HDHC-1
ORDER PART
NUMBER
LTC2914CGN-1
LTC2914IGN-1
LTC2914HGN-1
ORDER PART
NUMBER
16 V
CC
15 TMR
14 SEL
13 DIS
12
UV
11
OV
10 REF
9
GND
DHC PART
MARKING*
29141
29141
29141
GN PART
MARKING
29141
2914I1
2914H1
DHC PART
MARKING*
29142
29142
29142
GN PART
MARKING
29142
2914I2
2914H2
GN PACKAGE
16-LEAD PLASTIC SSOP
T
JMAX
= 150°C,
θ
JA
= 110°C/W
TOP VIEW
TOP VIEW
VH1
VL1
VH2
VL2
VH3
VL3
VH4
VL4
1
2
3
4
5
6
7
8
17
16 V
CC
15 TMR
14 SEL
13 DIS
12
UV
11
OV
10 REF
9
GND
VH1
VL1
VH2
VL2
VH3
VL3
VH4
VL4
DHC 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
1
2
3
4
5
6
7
8
LTC2914CDHC-2
LTC2914IDHC-2
LTC2914HDHC-2
ORDER PART
NUMBER
LTC2914CGN-2
LTC2914IGN-2
LTC2914HGN-2
GN PACKAGE
16-LEAD PLASTIC SSOP
T
JMAX
= 150°C,
θ
JA
= 110°C/W
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.
2914fa
2
LTC2914
ELECTRICAL CHARACTERISTICS
SYMBOL
V
SHUNT
ΔV
SHUNT
V
CC
V
CCR(MIN)
V
CC(UVLO)
ΔV
CC(UVHYST)
I
CC
V
REF
V
UOT
t
UOD
I
VHL
t
UOTO
V
LATCH(IH)
V
LATCH(IL)
I
LATCH
V
DIS(IH)
V
DIS(IL)
I
DIS
I
TMR(UP)
I
TMR(DOWN)
V
TMR(DIS)
V
OH
V
OL
PARAMETER
V
CC
Shunt Regulator Voltage
V
CC
Shunt Regulator Load Regulation
Supply Voltage (Note 3)
Minimum V
CC
Output Valid
Supply Undervoltage Lockout
Supply Undervoltage Lockout Hysteresis
Supply Current
Reference Output Voltage
Undervoltage/Overvoltage Voltage Threshold
Undervoltage/Overvoltage Voltage Threshold
to Output Delay
VHn, VLn Input Current
–40ºC < T
A
< 125ºC
UV/OV
Time-Out Period
OV
Latch Clear Input High
OV
Latch Clear Threshold Input Low
LATCH
Input Current
DIS Input High
DIS Input Low
DIS Input Current
TMR Pull-Up Current
TMR Pull-Down Current
Timer Disable Voltage
Output Voltage High
UV/OV
Output Voltage Low
UV/OV
V
DIS
> 0.5V
V
TMR
= 0V
–40ºC < T
A
< 125ºC
V
TMR
= 1.6V
–40ºC < T
A
< 125ºC
Referenced to V
CC
V
CC
= 2.3V, I
UV/OV
= –1μA
V
CC
= 2.3V, I
UV/OV
= 2.5mA
V
CC
= 1V, I
UV
= 100μA
V
LATCH
> 0.5V
C
TMR
= 1nF
–40ºC < T
A
< 125ºC
VHn = V
UOT
– 5mV or VLn = V
UOT
+ 5mV
DIS = 0V
V
CC
Rising, DIS = 0V
DIS = 0V
V
CC
= 2.3V to 6V
I
VREF
= ±1mA
–40ºC < T
A
< 125ºC
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 3.3V, VLn = 0.45V, VHn = 0.55V,
LATCH
= V
CC
, SEL = V
CC
,
DIS = Open unless otherwise noted. (Note 2)
CONDITIONS
I
CC
= 5mA
–40ºC < T
A
< 125ºC
I
CC
= 2mA to 10mA
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
MIN
6.2
6.2
2.3
1.9
5
0.985
0.985
492
50
TYP
6.6
6.6
200
MAX
6.9
7.0
300
V
SHUNT
1
UNITS
V
V
mV
V
V
V
mV
μA
V
V
mV
μs
nA
nA
ms
ms
V
V
μA
V
V
μA
μA
μA
μA
μA
mV
V
2
25
62
1
1
500
125
2.1
50
100
1.015
1.020
508
500
±15
±30
6
6
1.2
8.5
8.5
12.5
14
0.8
±1
1.2
0.8
1
–1.3
–1.2
1.3
1.2
–180
1
0.1
0.01
0.3
0.15
0.4
1.4
0.7
0.6
0.9
0.9
1.1
1.2
±25
±30
2
–2.1
–2.1
2.1
2.1
–270
3
–2.8
–2.8
2.8
2.8
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
–40ºC < T
A
< 125ºC
l
l
l
l
2914fa
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LTC2914
ELECTRICAL CHARACTERISTICS
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.
TIIMING DIAGRAMS
VHn Monitor Timing
VHn
V
UOT
t
UOD
UV
1V
2914 TD01
VLn Monitor Timing
VLn
V
UOT
t
UOD
OV
1V
2914 TD02
t
UOTO
t
UOTO
VHn Monitor Timing (TMR Pin Strapped to V
CC
)
VHn
V
UOT
t
UOD
UV
1V
2914 TD03
VLn Monitor Timing (TMR Pin Strapped to V
CC
)
VLn
V
UOT
t
UOD
OV
1V
2914 TD04
t
UOD
t
UOD
NOTE:
WHEN AN INPUT IS CONFIGURED AS A NEGATIVE SUPPLY MONITOR, VHn WILL TRIGGER AN OV CONDITION AND VLn WILL TRIGGER A UV CONDITION
TYPICAL PERFORMANCE CHARACTERISTICS
Specifications are at T
A
= 25°C, V
CC
= 3.3V unless otherwise noted.
Input Threshold Voltage
vs Temperature
0.505
0.504
THRESHOLD VOLTAGE, V
OUT
(V)
0.503
0.502
I
CC
(μA)
0.501
0.500
0.499
0.498
0.497
0.496
0.495
–50
–25
25
50
0
TEMPERATURE (°C)
75
100
2914 G01
Supply Current vs Temperature
75
V
CC
= 5V
70
65
V
CC
(V)
60
55
50
45
40
–50
V
CC
= 2.3V
6.3
V
CC
= 3.3V
6.7
6.6
6.5
6.4
6.8
V
CC
Shunt Voltage
vs Temperature
10mA
5mA
2mA
1mA
200μA
–25
0
25
50
TEMPERATURE (°C)
75
100
2914 G02
6.2
–50
–25
0
25
50
TEMPERATURE (°C)
75
100
2914 G03
2914fa
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LTC2914
TYPICAL PERFORMANCE CHARACTERISTICS
Specifications are at T
A
= 25°C, V
CC
= 3.3V unless otherwise noted.
Buffered Reference Voltage
vs Temperature
1.005
TYPICAL TRANSIENT DURATION (μs)
1.004
6.65
REFERENCE VOLTAGE, V
REF
(V)
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
0.995
–50
–25
25
50
0
TEMPERATURE (°C)
75
100
2914 G05
V
CC
Shunt Voltage vs I
CC
6.75
Transient Duration
vs Comparator Overdrive
700
600
500
400
300
200
V
CC
= 6V
100
V
CC
= 2.3V
V
CC
(V)
6.55
25°C
–40°C
85°C
6.35
RESET OCCURS
ABOVE CURVE
6.45
0
0.1
1
10
100
COMPARATOR OVERDRIVE PAST THRESHOLD (%)
2914 G06
2914 G04
Reset Timeout Period
vs Temperature
12
UV/OV TIMEOUT PERIOD, t
UOTO
(ms)
11
0.6
UV
VOLTAGE (V)
10
9
8
7
6
–50
0
C
TMR
= 1nF
0.8
UV
Output Voltage vs V
CC
5
V
CC
4
UV
VOLTAGE (V)
UV
Output Voltage vs V
CC
VHn = 0.55V
SEL = V
CC
3
0.4
UV
WITH
10k PULL-UP
0.2
UV
WITHOUT
10k PULL-UP
2
1
–25
0
25
50
TEMPERATURE (°C)
75
100
2914 G07
0
0.2
0.6
0.8
0.4
SUPPLY VOLTAGE, V
CC
(V)
1.0
2914 G08
0
0
1
3
4
2
SUPPLY VOLTAGE, V
CC
(V)
5
2914 G09
UV,
I
SINK
vs V
CC
5
PULL-DOWN CURRENT, I
UV
(mA)
VHn = 0.45V
SEL = V
CC
UV
AT 150mV
3
1.0
UV/OV
Voltage Output Low
vs Output Sink Current
10000
UV/OV
TIMEOUT PERIOD, t
UOTO
(ms)
25
30
2914 G11
Reset Timeout Period
vs Capacitance
4
UV/OV,
V
OL
(V)
0.8
85°C
1000
25°C
–40°C
0.6
100
2
UV AT 50mV
1
0.4
10
0.2
0
0
0
1
3
4
2
SUPPLY VOLTAGE, V
CC
(V)
5
2914 G10
0
5
10
15
20
I
UV/OV
(mA)
1
0.1
1
10
100
TMR PIN CAPACITANCE, C
TMR
(nF)
1000
2914 G12
2914fa
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