19-1280; Rev 6; 2/11
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
____________________________Features
The MAX6501–MAX6504 low-cost, fully integrated temperature switches assert a logic signal when their die
temperature crosses a factory-programmed threshold.
Operating from a +2.7V to +5.5V supply, these devices
feature two on-chip, temperature-dependent voltage
references and a comparator. They are available with
factory-trimmed temperature trip thresholds from -45°C
to +125°C in 10°C increments, and are accurate to
±0.5°C (typ) or ±6°C (max). These devices require no
external components and typically consume 30µA supply current. Hysteresis is pin-selectable at 2°C or 10°C.
The MAX6501/MAX6503 have an active-low, open-drain
output intended to interface with a microprocessor (µP)
reset input. The MAX6502/MAX6504 have an activehigh, push-pull output intended to directly drive fancontrol logic. The MAX6501/MAX6502 are offered with
hot-temperature thresholds (+35°C to +125°C), asserting when the temperature is above the threshold. The
MAX6503/MAX6504 are offered with cold-temperature
thresholds (-45°C to +15°C), asserting when the temperature is below the threshold.
The MAX6501–MAX6504 are offered in eight standard
temperature versions; contact the factory for pricing
and availability of nonstandard temperature versions.
They are available in a 5-pin SOT23 package.
♦ ±0.5°C (typical) Threshold Accuracy Over
Full Temperature Range
Typical Operating Circuit
+2.7V TO +5.5V
VCC
VCC
MAX6502
TOVER
GND
GND
HYST
INT
♦ No External Components Required
♦ Low Cost
♦ 30µA Supply Current
♦ Factory-Programmed Thresholds from
-45°C to +125°C in 10°C Increments
♦ Open-Drain Output (MAX6501/MAX6503)
Push-Pull Output (MAX6502/MAX6504)
♦ Pin-Selectable 2°C or 10°C Hysteresis
♦ SOT23-5 Package
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX6501UK_ _ _ _+T
-55°C to +125°C
5 SOT23
MAX6502UK_ _ _ _+T
-55°C to +125°C
5 SOT23
MAX6503UK_ _ _ _+T
-55°C to +125°C
5 SOT23
MAX6504UK_ _ _ _+T
-55°C to +125°C
5 SOT23
Note: These parts are offered in eight standard temperature
versions with a minimum order of 2,500 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 MAX6501UKP065+T describes a
MAX6501 in a SOT23 package with a +65°C threshold.
Contact the factory for pricing and availability of nonstandard
temperature versions (minimum order 10,000 pieces).
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
________________________Applications
μP
GND
µP Temperature Monitoring in High-Speed
Computers
Temperature Control
Temperature Alarms
Fan Control
Selector Guide and Pin Configurations appear at end of
data sheet.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1
MAX6501–MAX6504
________________General Description
MAX6501–MAX6504
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (VCC) Range....................................-0.3V to +7V
TOVER (MAX6501) ...................................................-0.3V to +7V
TOVER (MAX6502) .....................................-0.3V to (VCC + 0.3V)
TUNDER (MAX6503) ................................................-0.3V to +7V
TUNDER (MAX6504) ..................................-0.3V to (VCC + 0.3V)
All Other Pins..............................................-0.3V to (VCC + 0.3V)
Input Current (all pins) ........................................................20mA
Output Current (all pins) .....................................................20mA
Continuous Power Dissipation (TA = +70°C)
SOT23 (derate 3.1mW/°C above +70°C) ......................247mW
Operating Temperature Range .........................-55°C to +135°C
Storage Temperature Range .............................-65°C to +165°C
Lead Temperature (soldering, 10s) .................................+300°C
Soldering Temperature (reflow) .......................................+260°C
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.
ELECTRICAL CHARACTERISTICS
(VCC = +2.7V to +5.5V, RPULLUP = 100kΩ (MAX6501/MAX6503 only), TA = TMIN to TMAX, unless otherwise noted. Typical values are
at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Supply Voltage Range
VCC
Supply Current
ICC
Temperature Threshold
Accuracy (Note 2)
Temperature Threshold
Hysteresis
HYST Input Threshold
(Note 3)
Output Voltage High
Output Voltage Low
Open-Drain Output Leakage
Current
ΔTTH
THYST
CONDITIONS
MIN
TYP
2.7
V
30
85
µA
-6
±0.5
+6
-15°C to +15°C
-4
±0.5
+4
+35°C to +65°C
-4
±0.5
+4
+75°C to +125°C
-6
±0.5
+6
HYST = GND
2
HYST = VCC
10
VOL
0.2 x VCC
0.8 x VCC
ISOURCE = 800µA, VCC > 4.5V
(MAX6502/MAX6504 only)
VCC - 1.5
V
V
ISINK = 1.2mA, VCC > 2.7V
0.3
ISINK = 3.2mA, VCC > 4.5V
0.4
VCC = 2.7V, VTUNDER = 5.5V (MAX6503),
VTOVER = 5.5V (MAX6501)
°C
°C
0.8 x VCC
VIL
ISOURCE = 500µA, VCC > 2.7V
(MAX6502/MAX6504 only)
UNITS
5.5
-45°C to -25°C
VIH
VOH
MAX
10
V
nA
Note 1: 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design.
Note 2: The MAX6501–MAX6504 are available with internal, factory-programmed temperature trip thresholds from -45°C to +125°C
in +10°C increments (see Selector Guide).
Note 3: Guaranteed by design.
2
_______________________________________________________________________________________
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
MAX6501–MAX6504
__________________________________________Typical Operating Characteristics
(VCC = +5V, RPULLUP = 100kΩ (MAX6501/MAX6503), TA = +25°C, unless otherwise noted.)
40
30
20
10
30
OUTPUT SOURCE RESISTANCE (Ω)
35
SUPPLY CURRENT (μA)
50
800
MAX6501 TOC01
40
MAX6501 TOC-A
PERCENTAGE OF PARTS SAMPLED (%)
SAMPLE SIZE = 300
25
20
15
10
5
0
-3
-2
-1
0
1
2
3
4
5
600
500
400
300
VCC = 5.0V
200
-25
5
35
65
95
125
-55
TEMPERATURE (°C)
OUTPUT SINK RESISTANCE
vs. TEMPERATURE
VCC = 3.3V
0
-55
ACCURACY (°C)
VCC = 2.7V
700
100
0
-5 -4
-25
5
35
65
125
SOT23 THERMAL STEP RESPONSE
IN STILL AIR
MAX6501 TOC5
MAX6501 TOC4
MAX6501 TOC03
VCC = 2.7V
140
95
TEMPERATURE (°C)
SOT23 THERMAL STEP RESPONSE
IN PERFLUORINATED FLUID
160
MAX6501 TOC02
TRIP THRESHOLD ACCURACY
60
OUTPUT SINK RESISTANCE (Ω)
MAX6502/MAX6504
OUTPUT SOURCE RESISTANCE
vs. TEMPERATURE
SUPPLY CURRENT
vs. TEMPERATURE
+100°C
+100°C
120
100
VCC = 3.3V
80
+12.5°C/div
+15°C/div
VCC = 5.0V
60
MOUNTED ON 0.75in2
OF 2 oz. COPPER
40
20
MOUNTED ON 0.75in2
OF 2 oz. COPPER
+25°C
+25°C
0
-55
-25
5
35
65
95
125
20sec/div
5sec/div
TEMPERATURE (°C)
MAX6501 STARTUP AND POWER-DOWN
(T < TTH)
HYSTERESIS
vs. TRIP TEMPERATURE
MAX6501 TOC07
MAX6503
MAX6504
HYST = VCC
HYSTERESIS (°C)
12
MAX6501 TOC8
16
14
MAX6501 STARTUP DELAY
(T > TTH)
MAX6501
MAX6502
HYST = VCC
MAX6501 TOC07A
A
A
10
8
6
MAX6501
MAX6502
HYST = GND
MAX6503
MAX6504
HYST = GND
4
2
0
-45
-25
-5
15
35
55
75
TRIP TEMPERATURE (°C)
95
B
B
115
TRACE A: TOVER VOLTAGE, RPULLUP = 100kΩ
TRACE B: VCC PULSE DRIVEN FROM 3.3V CMOS LOGIC OUTPUT
TRACE A: TOVER VOLTAGE, RPULLUP = 100kΩ
TRACE B: VCC PULSE DRIVEN FROM 3.3V CMOS LOGIC OUTPUT
_______________________________________________________________________________________
3
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
MAX6501–MAX6504
Pin Description
PIN
NAME
MAX6502
MAX6503
MAX6504
1, 2
1, 2
1, 2
1, 2
GND
Ground. Not internally connected. Connect both ground pins
together close to the chip. Pin 2 provides the lowest thermal
resistance to the die.
3
3
3
3
HYST
Hysteresis Input. Connect HYST to GND for 2°C hysteresis, or
connect to VCC for 10°C hysteresis.
4
4
4
4
VCC
5
—
—
—
TOVER
Open-Drain, Active-Low Output. TOVER goes low when the die
temperature exceeds the factory-programmed temperature
threshold. Connect to a 100kΩ pullup resistor. May be pulled
up to a voltage higher than VCC.
—
5
—
—
TOVER
Push-Pull Active-High Output. TOVER goes high when the die temperature exceeds the factory-programmed temperature threshold.
Supply Input (+2.7V to +5.5V)
—
—
5
—
TUNDER
Open-Drain, Active-Low Output. TUNDER goes low when the
die temperature goes below the factory-programmed temperature threshold. Connect to a 100kΩ pullup resistor. May be
pulled up to a voltage higher than VCC.
—
—
—
5
TUNDER
Push-Pull Active-High Output. TUNDER goes high when the die temperature falls below the factory-programmed temperature threshold.
________________General Description
The MAX6501–MAX6504 fully integrated temperature
switches incorporate two temperature-dependent references and a comparator. One reference exhibits a positive temperature coefficient and the other a negative
temperature coefficient (Figure 1). The temperature at
which the two reference voltages are equal determines
the temperature trip point. Pin-selectable 2°C or 10°C
hysteresis keeps the output from oscillating when the
die temperature approaches the threshold temperature.
The MAX6501/MAX6503 have an active-low, opendrain output structure that can only sink current. The
MAX6502/MAX6504 have an active-high, push-pull output structure that can sink or source current. The internal power-on reset circuit guarantees the output is at
TTH = +25°C state at startup for 50µs.
The MAX6501–MAX6504 are available with factorypreset temperature thresholds from -45°C to +125°C in
10°C increments. Table 1 lists the available temperature
threshold ranges. The MAX6501/MAX6503 outputs are
intended to interface with a microprocessor (µP) reset
input (Figure 2). The MAX6502/MAX6504 outputs are
intended for applications such as driving a fan control
(Figure 3).
4
FUNCTION
MAX6501
Table 1. Factory-Programmed Threshold
Range
PART
THRESHOLD (TTH) RANGE
MAX6501
+35°C < TTH < +125°C
MAX6502
+35°C < TTH < +125°C
MAX6503
-45°C < TTH < +15°C
MAX6504
-45°C < TTH < +15°C
Hysteresis Input
The HYST pin is a CMOS-compatible input that selects
hysteresis at either a high level (10°C for HYST = VCC)
or a low level (2°C for HYST = GND). Hysteresis prevents the output from oscillating when the temperature
approaches the trip point. The HYST pin should not be
left unconnected. Drive HYST close to ground or VCC.
Other input voltages cause increased supply current.
The actual amount of hysteresis depends on the part’s
programmed trip threshold (see the Typical Operating
Characteristics).
_______________________________________________________________________________________
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
V
TOVER
MAX6501–MAX6504
TOVER
MAX6501
WITH 100kΩ PULLUP
POSITIVE
TEMPCO
REFERENCE
NEGATIVE
TEMPCO
REFERENCE
HYST
NETWORK
HYST
COLD
+25°C
TTH
HOT
TEMP
MAX6501
MAX6502
V
TOVER
TOVER
POSITIVE
TEMPCO
REFERENCE
NEGATIVE
TEMPCO
REFERENCE
HYST
NETWORK
HYST
COLD
+25°C
TTH
HOT
TEMP
MAX6502
TUNDER
MAX6503
WITH 100kΩ PULLUP
V
TUNDER
POSITIVE
TEMPCO
REFERENCE
NEGATIVE
TEMPCO
REFERENCE
HYST
NETWORK
HYST
COLD
TTH
+25°C
HOT
TEMP
MAX6503
V
TUNDER
MAX6504
TUNDER
POSITIVE
TEMPCO
REFERENCE
NEGATIVE
TEMPCO
REFERENCE
HYST
NETWORK
HYST
COLD
TTH
+25°C
HOT
TEMP
MAX6504
Figure 1. Block and Functional Diagrams
_______________________________________________________________________________________
5
MAX6501–MAX6504
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
+3.3V
+5V
VCC
VCC
RPULLUP
100kΩ
μP
μP
MAX6501
INT
SHUTDOWN
OR
RESET
TOVER
HEAT
HYST
HYST
HEAT
MAX6502
FAN
GND GND TOVER
GND
GND
Figure 2. Microprocessor Alarm/Reset
Applications Information
Thermal Considerations
The MAX6501–MAX6504 supply current is typically
30µA. When used to drive high-impedance loads, the
devices dissipate negligible power. Therefore, the die
temperature is essentially the same as the package
temperature. The key to accurate temperature monitoring is good thermal contact between the MAX6501–
MAX6504 package and the device being monitored. In
some applications, the SOT23 package may be small
enough to fit underneath a socketed µP, allowing the
device to monitor the µP’s temperature directly. Use the
monitor’s output to reset the µP, assert an interrupt, or
trigger an external alarm.
Accurate temperature monitoring depends on the thermal resistance between the device being monitored
and the MAX6501–MAX6504 die. Heat flows in and out
of plastic packages, primarily through the leads. Pin 2
of the SOT23-5 package provides the lowest thermal
resistance to the die. Short, wide copper traces leading
to the temperature monitor ensure that heat transfers
quickly and reliably.
The rise in die temperature due to self-heating is given
by the following formula:
ΔTJ = PDISSIPATION x θJA
where P DISSIPATION is the power dissipated by the
MAX6501–MAX6504, and θJA is the package’s thermal
resistance.
The typical thermal resistance is 140°C/W for the
SOT23 package. To limit the effects of self-heating,
minimize the output currents. For example, if the
MAX6501 or MAX6503 sink 1mA, the 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 temperature in
the SOT23.
6
VCC
VCC
Figure 3. Overtemperature Fan Control
Temperature-Window Alarm
The MAX6501–MAX6504 temperature switch outputs
assert when the die temperature is outside the factoryprogrammed range. Combining the outputs of two
devices creates an over/undertemperature alarm. The
MAX6501/MAX6503 and the MAX6502/MAX6504 are
designed to form two complementary pairs, each 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. The MAX6502/MAX6504
push/pull output stages can be ORed to produce a thermal out-of-range alarm. More favorably, a MAX6501/
MAX6503 can be directly wire-ORed with a single external resistor to accomplish the same task (Figure 4).
The temperature window alarms shown in Figure 4 can
be used to accurately determine when a device’s temperature falls out of the -5°C to +75°C range. The thermal-overrange signal can be used to assert a thermal
shutdown, power-up, recalibration, or other temperaturedependent function.
Low-Cost, Fail-Safe
Temperature Monitor
In high-performance/high-reliability applications, multiple temperature monitoring is important. The high-level
integration and low cost of the MAX6501–MAX6504
facilitate the use of multiple temperature monitors to increase system reliability. Figure 5’s application uses
two MAX6502s with different temperature thresholds to
ensure that fault conditions that can overheat the monitored device cause no permanent damage. The first
temperature monitor activates the fan when the die
temperature exceeds +45°C. The second MAX6502
triggers a system shutdown if the die temperature
reaches +75°C. The second temperature monitor’s output asserts when a wide variety of destructive fault conditions occur, including latchups, short circuits, and
cooling-system failures.
_______________________________________________________________________________________
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
MAX6501–MAX6504
+5V
+5V
VCC
VCC
MAX6502_ _P075
GND
GND
HEAT
OVERTEMP
HYST
TOVER
OUT OF RANGE
VCC
MAX6502_ _P075
GND
GND
HYST
TEMPERATURE
FAULT
TOVER
μP
TUNDER
UNDERTEMP
MAX6504_ _N005
FAN
CONTROL
HYST
GND
HEAT
GND
VCC
TOVER
HYST
MAX6502_ _P045
+5V
RPULL-UP
100k
GND
OUT OF RANGE
GND
VCC
VCC
TOVER
TUNDER
MAX6501_ _P075
Figure 5. Low-Power, High-Reliability, Fail-Safe Temperature
Monitor
MAX6503_ _N005
GND
GND
GND
HYST
GND
HYST
Figure 4. Temperature-Window Alarms
Table 2. Device Marking Codes
DEVICE
MAX6501UKP035
MAX6501UKP045
MAX6501UKP055
MAX6501UKP065
MAX6501UKP075
MAX6501UKP085
MAX6501UKP095
MAX6501UKP105
MAX6501UKP115
MAX6501UKP125
MAX6502UKP035
MAX6502UKP045
MAX6502UKP055
MAX6502UKP065
MAX6502UKP075
MAX6502UKP085
MAX6502UKP095
CODE
MINIMUM
ORDER
ABZF
ABZR
ACFW
ABZS
ACFV
ACDP
ABZT
ACFU
ACAG
ADQK
ABZG
ABZU
ACGC
ABZV
ACGB
ACGA
ABZW
10k
2.5k
2.5k
2.5k
2.5k
2.5k
2.5k
10k
2.5k
25k
10k
2.5k
2.5k
2.5k
2.5k
2.5k
2.5k
DEVICE
CODE
MINIMUM
ORDER
MAX6502UKP105
ACFZ
10k
MAX6502UKP115
MAX6502UKP125
ACFY
ADUD
2.5k
25k
MAX6503UKN045
ADIZ
10k
MAX6503UKN035
MAX6503UKN025
MAX6503UKN015
MAX6503UKN005
MAX6503UKP005
MAX6503UKP015
MAX6504UKN045
ADVS
ADVR
ACFX
ADNZ
ABZX
ADPN
ACAX
10k
10k
2.5k
10k
2.5k
10k
10k
MAX6504UKN035
MAX6504UKN025
MAX6504UKN015
MAX6504UKN005
MAX6504UKP005
MAX6504UKP015
ADVU
ADVT
ACGD
ADVX
ABZY
ADKE
10k
10k
2.5k
10k
2.5k
10k
_______________________________________________________________________________________
7
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
MAX6501–MAX6504
Selector Guide
PART
MAX6501 MAX6502 MAX6503 MAX6504
TOP VIEW
OUTPUT
STAGE
OpenDrain
Push-Pull
OpenDrain
Push-Pull
TRIP TEMP
THRESHOLD
Hot
Hot
Cold
Cold
-45
✓
✓
-35
✓
✓
-25
✓
✓
-15
✓
✓
-5
✓
✓
+5
✓
✓
+15
✓
✓
STANDARD TEMPERATURE THRESHOLDS (°C)
8
Pin Configurations
+35
✓
✓
+45
✓
✓
+55
✓
✓
+65
✓
✓
+75
✓
✓
+85
✓
✓
+95
✓
✓
+105
✓
✓
+115
✓
✓
+125
✓
✓
GND 1
GND 2
5 TOVER
GND 1
(TOVER)
MAX6501
MAX6502
HYST 3
GND 2
4 VCC
5 TUNDER
(TUNDER)
MAX6503
MAX6504
HYST 3
SOT23
4 VCC
SOT23
( ) ARE FOR MAX6502.
( ) ARE FOR MAX6504.
Chip Information
SUBSTRATE CONNECTED TO GND
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
5 SOT23
U5+2
21-0057
90-0174
_______________________________________________________________________________________
Low-Cost, +2.7V to +5.5V, Micropower
Temperature Switches in SOT23
REVISION
NUMBER
REVISION
DATE
5
10/06
6
2/11
DESCRIPTION
In Table 2 updated the device marking codes for MAX6503UKN035,
MAX6503UKN025, MAX6503UKN005, MAX6503UKP015, MAX6504UKN035,
MAX6504UKN025, and MAX6504UKN005
Removed the TO-220 package from entire data sheet; changed all leaded parts to
lead(Pb)-free parts in the Ordering Information table; in the Absolute Maximum Ratings
section changed the continuous power dissipation numbers (7.1mW/°C to 3.1mW/°C
and 571mW to 247mW) and added the soldering temperature; added the Package
Information table
PAGES
CHANGED
7
All
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 9
© 2011 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.
MAX6501–MAX6504
Revision History
工商网监
湘ICP备2023018690号
