General Description
The MAX6514/MAX6515 low-cost, fully integrated temper-
ature switches assert a logic signal when their die tem-
perature crosses a factory-programmed threshold.
Operating from a 2.7V to 5.5V supply, these devices fea-
ture a fixed voltage reference, an analog temperature
sensor, and a comparator. They are available with facto-
ry-trimmed temperature trip thresholds from -45°C to
+15°C and +35°C to +115°C in 10°C increments, and are
accurate to ±1°C (typ). These devices require no external
components and typically consume 22µA of supply cur-
rent. Hysteresis is pin selectable at 2°C or 10°C.
The MAX6514/MAX6515 are offered with hot-tempera-
ture thresholds (+35°C to +115°C), asserting when the
temperature is above the threshold or with cold-temper-
ature thresholds (-45°C to +15°C), asserting when the
temperature is below the threshold. The MAX6514/
MAX6515 can be used over a -35°C to +125°C range
with a supply voltage of 2.7V to 5.5V. For applications
sensing temperature down to -45°C, a supply voltage
above 4.5V is required.
The MAX6514 has an active-high, push-pull output. The
MAX6515 has an active-low, open-drain output. These
devices are available in a space-saving 5-pin SOT23
package and operate over the -55°C to +125°C tem-
perature range.
Applications
Over/Undertemperature Protection
Fan Control
Test Equipment
Temperature Control
Temperature Alarms
Notebook, Desktop PCs
RAID
Servers
Features
♦High-Accuracy +1.5°C (max) over -15°C to +65°C
Temperature Range
♦Low-Power Consumption: 22µA Typical Current
♦Factory-Programmed Thresholds from -45°C to
+115°C in 10°C Increments
♦Open-Drain or Push-Pull Outputs
♦Pin-Selectable 2°C or 10°C Hysteresis
♦Low Cost
MAX6514/MAX6515
Low-Cost, 2.7V to 5.5V Temperature Switches
in a SOT23
________________________________________________________________ Maxim Integrated Products 1
Ordering Information
19-3147; Rev 0; 1/04
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Pin Configurations and Functional Diagram appear at end of
data sheet.
PART TEMP RANGE PIN-
PACKAGE
MAX6514UK_ _ _ _-T*
-55°C to +125°C
5 SOT23-5
MAX6515UK_ _ _ _-T*
-55°C to +125°C
5 SOT23-5
*These parts are offered in 16 standard temperature versions
with a minimum order of 2500 pieces. To complete the suffix
information, add P or N for positive or negative trip temperature,
and select an available trip point in degrees centigrade. For
example, the MAX6514UKP065-T describes a MAX6514 in a
5-pin SOT23 package with a +65°C threshold in tape and reel
(2.5k minimum order). Contact the factory for pricing and avail-
ability.
Typical Operating Circuit
MAX6515 MICROCONTROLLER
VCC
0.1µF
VCC
VCC
100kΩ
GND
GND HYST
INT
TOVER
GND
MAX6514/MAX6515
Low-Cost, 2.7V to 5.5V Temperature Switches
in a SOT23
2_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC = 2.7V to 5.5V, RPULLUP = 100kΩ, (open-drain output only), TA= -55°C to +125°C, unless otherwise noted. Typical values are
at TA = +25°C.) (Note 1)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
Note 1: 100% production tested at TA = +25°C. Specifications over temperature are guaranteed by design.
Note 2: The MAX6514/MAX6515 are available with internal factory-programmed temperature trip thresholds from -45°C to +15°C
and +35°C to +115°C in 10°C increments.
Note 3: VCC must be greater than 4.5V for a switching threshold of -45°C.
Note 4: Guaranteed by design.
All Voltages Are Referenced to GND
VCC ..........................................................................-0.3V to +6V
TOVER, TUNDER (open drain)................................ -0.3V to +6V
TOVER, TUNDER (push-pull)....................... -0.3V to VCC + 0.3V
HYST.............................................................-0.3V to VCC + 0.3V
Continuous Power Dissipation
5-Pin SOT23 (derate 7.1mW/°C above +70°C)............571mW
Operating Temperature Range ........................-55°C to +125°C
Junction Temperature..................................................... +150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) ................................ +300°C
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX
UNITS
Supply Voltage Range VCC 2.7 5.5 V
Hot-temperature thresholds
(+35°C to +115°C) 22 40
Supply Current ICC Cold-temperature thresholds
(-45°C to +15°C) 40
µA
-15°C to +65°C
-1.5 +1.5
+75°C to +115°C
-2.5 +2.5
Temperature Threshold Accuracy
(Note 2) ∆TTH
-45°C to -25°C (Note 3) -3 +3
°C
HYST = VCC 2
Temperature Threshold
Hysteresis THYST HYST = GND 10 °C
VIH 0.8 x VCC
HYST Input Threshold (Note 4) VIL
0.2 x VCC
V
ISOURCE = 500µA, VCC > 2.7V 0.8 x VCC
Logic Output Voltage High
(Push-Pull) VOH ISOURCE = 800µA, VCC > 4.5V VCC - 1.5 V
ISINK = 1.2mA, VCC > 2.7V 0.3
Logic Output Voltage Low
(Push-Pull and Open Drain) VOL ISINK = 3.2mA, VCC > 4.5V 0.4 V
Open-Drain Output Leakage
Current VCC = 2.7V, open-drain output = 5.5V 10 nA
MAX6514/MAX6515
Low-Cost, 2.7V to 5.5V Temperature Switches
in a SOT23
_______________________________________________________________________________________ 3
TRIP THRESHOLD ACCURACY
MAX6514 toc01
ACCURACY (°C)
PERCENTAGE OF PARTS SAMPLED (%)
-0.25 TO
-0.5
-0.75 TO
-1.0
10
20
30
40
50
0
-1.25 TO
-1.5
0.25 TO
0.5
0.75 TO
1.0
1.25 TO
1.5
SAMPLE SIZE = 147
SUPPLY CURRENT
vs. TEMPERATURE
MAX6514 toc02
TEMPERATURE (°C)
SUPPLY CURRENT (µA)
105856545255-15-35
5
10
15
20
25
30
0
-55 125
TOVER/TUNDER OUTPUT VOLTAGE HIGH
vs. SOURCE CURRENT
MAX6514 toc03
ISINK (mA)
VOH (V)
987654321
1
2
3
4
5
0
010
MAX6514 toc04
ISINK (mA)
VOL (V)
987654321
100
200
300
400
500
0
010
TOVER/TUNDER OUTPUT VOLTAGE LOW
vs. SINK CURRENT
STARTUP DELAY (TEMP > TTH)
MAX6514 toc06
TIME = 100µs
VCC
(2V/div)
TOVER
(2V/div)
Typical Operating Characteristics
(VCC = 4.5V, TA = +25°C, unless otherwise noted.)
MAX6514/MAX6515
Low-Cost, 2.7V to 5.5V Temperature Switches
in a SOT23
4_______________________________________________________________________________________
Pin Description
Detailed Description
The MAX6514/MAX6515 fully integrated temperature
switches incorporate a fixed reference, an analog tem-
perature sensor, and a comparator. Pin-selectable 2°C
or 10°C hysteresis keeps the digital output from oscil-
lating when the die temperature approaches the
threshold temperature. The MAX6514 has an active-
high, push-pull output structure that can sink or source
current. The MAX6515 has an active-low, open-drain
output structure that can only sink current. The internal
power-on reset circuit guarantees the logic output is at
its +25°C state for at least 50µs.
Hysteresis Input
The HYST input selects the devices’ temperature hys-
teresis and prevents the output from oscillating when the
temperature approaches the trip point. Connect HYST to
VCC for 2°C hysteresis or to GND for 10°C hysteresis.
Logic Temperature Indicators
Overtemperature Indicator (Hot Thresholds)
TOVER and TOVER designations apply to thresholds
above TA= +25°C (+35°C, +45°C, +55°C, +65°C,
+75°C, +85°C, +95°C, +105°C, and +115°C). All “hot”
thresholds are positive temperatures.
The overtemperature indicator output is open drain
active low (TOVER) or push-pull active high (TOVER).
TOVER goes low when the die temperature exceeds
the factory-programmed temperature threshold. TOVER
should be pulled up to a voltage no greater than 5.5V
with a 100kΩpullup resistor. TOVER is a push-pull
active-high CMOS output that goes high when the die
temperature exceeds the factory-programmed temper-
ature threshold.
Undertemperature Indicator (Cold Thresholds)
TUNDER and TUNDER designations apply to thresh-
olds below TA= +25°C (+15°C, +5°C, -5°C, -15°C,
-25°C, -35°C, -45°C). The undertemperature indicator
output is open-drain, active low (TUNDER) or push-pull,
active high (TUNDER). TUNDER goes low when the die
temperature goes below the factory-programmed tem-
perature threshold. TUNDER should be pulled up to a
voltage no greater than 5.5V with a 100kΩpullup resis-
tor. TUNDER is a push-pull active-high CMOS output
that goes high when the die temperature falls below the
factory-programmed temperature threshold.
PIN
MAX6514 MAX6515 NAME
FUNCTION
1, 2 1, 2 GND Ground
33HYST Hysteresis Input. Connect to VCC for 2°C of hysteresis or to GND for 10°C hysteresis.
44V
CC Input Supply. Bypass to ground with a 0.1µF capacitor.
5—
TOVER
Push-Pull Active-High Output (Hot Threshold). TOVER goes high when the die temperature
exceeds the factory-programmed hot-temperature threshold.
—5
TOVER
Open-Drain, Active-Low Output (Hot Threshold). TOVER goes low when the die temperature
exceeds the factory-programmed hot-temperature threshold. Connect to a 100kΩ pullup
resistor. Can be pulled up to a voltage higher than VCC.
5—
TUNDER
Push-Pull Active-High Output (Cold Threshold). TUNDER goes high when the die temperature
falls below the factory-programmed cold-temperature threshold.
—5
TUNDER
Open-Drain, Active-Low Output (Cold Threshold). TUNDER goes low when the die
temperature goes below the factory-programmed cold-temperature threshold. Connect to a
100kΩ pullup resistor. Can be pulled up to a voltage higher than VCC.
Applications Information
Temperature-Window Alarm
The MAX6515 logic output asserts when the die tem-
perature is outside the factory-programmed range.
Combining the outputs of two devices creates an
over/undertemperature alarm. Two MAX6515s are used
to form two complementary pairs, containing one cold
trip-point output and one hot trip-point output. The
assertion of either output alerts the system to an out-of-
range temperature (Figure 1).
The thermal overrange signal can be used to assert a
thermal shutdown, power-up, recalibration, or other
temperature-dependent function.
Low-Cost, Fail-Safe Temperature
In high-performance/high-reliability applications, multi-
ple temperature monitoring is important. The high-level
integration and low cost of the MAX6514/MAX6515
facilitate the use of multiple temperature monitors to
increase system reliability. The Figure 2 application
uses two MAX6514s with different hot-temperature
thresholds to ensure that fault conditions that can over-
heat the monitored device cause no permanent dam-
age. The first temperature monitor activates the fan
when the die temperature exceeds +45°C. The second
MAX6514 triggers a system shutdown if the die temper-
ature reaches +75°C, preventing damage from a wide
variety of destructive fault conditions, including
latchups, short circuits, and cooling-system failures.
Thermal Considerations
The MAX6514/MAX6515 supply current is typically
22µA. When used to drive high-impedance loads, the
devices dissipate negligible power and self-heating
effects are minimized.
Accurate temperature monitoring depends on the ther-
mal resistance between the device being monitored
and the MAX6514/MAX6515 die. Heat flows in and out
of plastic packages, primarily through the leads. Pin 2
of the 5-pin SOT23 package provides the lowest ther-
mal resistance to the die. Short, wide copper traces
between the MAX6514/MAX6515 and the objects
whose temperature is being monitored ensure heat
transfers occur quickly and reliably. The rise in die tem-
perature due to self-heating is given by the following
formula:
∆TJ= PDISSIPATION x θJA
where PDISSIPATION is the power dissipated by the
MAX6514/MAX6515, and θJA is the thermal resistance
of the package.
The typical thermal resistance is +140°C/W for the 5-
pin SOT23 package. To limit the effects of self-heating,
minimize the output current. For example, if the
MAX6514/MAX6515 sink 1mA, the open-drain output
voltage is guaranteed to be less than 0.3V. Therefore,
an additional 0.3mW of power is dissipated within the
IC. This corresponds to a 0.042°C shift in the die tem-
perature in the 5-pin SOT23 package.
MAX6514/MAX6515
Low-Cost, 2.7V to 5.5V Temperature Switches
in a SOT23
_______________________________________________________________________________________ 5
MAX6515UKP075 MAX6515UKN005
VCC VCC
+5V
100kΩ
GND
GND HYST
TUNDER
TOVER
GND
OUT OF RANGE
GND HYST
VCC
+5V
SYSTEM
SHUTDOWN
MAX6514UKP075
GND
µP
GND HYST
TOVER
VCC FAN
CONTROL
MAX6514UKP045
GND
GND
TOVERHYST
GND
HEAT
HEAT
Figure 1. Temperature-Window Alarms Using the MAX6515
Figure 2. Low-Power, High-Reliability, Fail-Safe Temperature
Monitor
MAX6514/MAX6515
Low-Cost, 2.7V to 5.5V Temperature Switches
in a SOT23
6_______________________________________________________________________________________
Table 1. Top Marks
PART TOP MARK
MAX6514UKN005 AEKU
MAX6514UKN015 AEKV
MAX6514UKN025 AEKW
MAX6514UKN035 AECV
MAX6514UKN045 AEKX
MAX6514UKP005 AEKY
MAX6514UKP015 AEKZ
MAX6514UKP035 AELA
MAX6514UKP045 AELB
MAX6514UKP055 AELC
MAX6514UKP065 AELD
MAX6514UKP075 AECW
MAX6514UKP085 AELE
MAX6514UKP095 AELF
MAX6514UKP105 AELG
MAX6514UKP115 AELH
PART TOP MARK
MAX6515UKN005 AEMK
MAX6515UKN015 AEML
MAX6515UKN025 AEMM
MAX6515UKN035 AECX
MAX6515UKN045 AEMN
MAX6515UKP005 AEMO
MAX6515UKP015 AEMP
MAX6515UKP035 AEMQ
MAX6515UKP045 AEMR
MAX6515UKP055 AEMS
MAX6515UKP065 AEMT
MAX6515UKP075 AECY
MAX6515UKP085 AEMU
MAX6515UKP095 AEMV
MAX6515UKP105 AEMW
MAX6515UKP115 AEMX
GND
VCC
HOT THRESHOLDS (+35°C TO +115°C)
HYST
15(TOVER)
TOVER
GND
(MAX6514)
MAX6515
SOT23
TOP VIEW
2
34
GND
VCC
COLD THRESHOLDS (-45°C TO +15°C)
HYST
15(TUNDER)
TUNDER
GND
(MAX6514)
MAX6515
SOT23
2
34
Pin Configurations
MAX6514/MAX6515
Low-Cost, 2.7V to 5.5V Temperature Switches
in a SOT23
_______________________________________________________________________________________ 7
Chip Information
TRANSISTOR COUNT: 1808
PROCESS: BiCMOS
MAX6514/MAX6515 Functional Diagram
FIXED
REFERENCE
HYST
NETWORK HYST
TOVER
TOVER
COLD
MAX6514 (HOT THRESHOLD)
+25°CT
TH HOT TEMP
V
NEGATIVE
TEMPCO
SENSOR
MAX6514
FIXED
REFERENCE
HYST
NETWORK HYST
TOVER TOVER
COLD
MAX6515 (HOT THRESHOLD)
WITH 100kΩ PULLUP
+25°CT
TH HOT TEMP
V
NEGATIVE
TEMPCO
SENSOR
MAX6515
FIXED
REFERENCE
HYST
NETWORK HYST
TUNDER
TUNDER
COLD
MAX6514 (COLD THRESHOLD)
+25°C
TTH HOT TEMP
V
NEGATIVE
TEMPCO
SENSOR
MAX6514
FIXED
REFERENCE
HYST
NETWORK HYST
TUNDER
COLD
MAX6515 (COLD THRESHOLD)
WITH 100kΩ PULLUP
+25°C
TTH HOT TEMP
V
NEGATIVE
TEMPCO
SENSOR
MAX6515
TUNDER
MAX6514/MAX6515
Low-Cost, 2.7V to 5.5V Temperature Switches
in a SOT23
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
©2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
SOT-23 5L .EPS
E
1
1
21-0057
PACKAGE OUTLINE, SOT-23, 5L