MAXIM MAX6510

19-1819; Rev 1; 11/03
Low-Cost, Remote SOT Temperature Switches
♦ Continuously Measure External Junction
Temperature
♦ Factory-Programmed Temperature Threshold
from +45°C to +125°C in 10°C Increments
♦ Insensitive to Series Parasitic Resistance
The MAX6511/MAX6512/MAX6513 operate from a
+3.0V to +5.5V supply and typically consume 400µA of
supply current. They are available in a small 6-pin
SOT23 package.
♦ +3.0V to +5.5V Supply Range
♦ Active-Low CMOS Output (MAX6511) or OpenDrain Output for Overtemperature Alarm
(MAX6512) or Active-High Output (MAX6513) for
Direct Fan Control
♦ <100ms Response Time
♦ Accuracy
±3°C (TREMOTE = +45°C to +125°C, TA = -5°C to +55°C)
±5°C (TREMOTE = +45°C to +125°C, TA = -40°C to +85°C)
♦ Pin-Selectable 5°C or 10°C Hysteresis
♦ 400µA Average Current Consumption
♦ 6-Pin SOT23 Package
Ordering Information
________________________Applications
CPU Temperature Monitoring in High-Speed
Computers
Multichip Modules
Battery Packs
Temperature Control
Temperature Alarms
Fan Control
Pin Configuration
TOP VIEW
VDD 1
GND 2
MAX6511
MAX6512
MAX6513
HYST 3
6
DXP
5
DXN
4
TOVER (TOVER)
PART*
TEMP RANGE
PINOUTPUT
PACKAGE
CMOS
(Active-Low)
MAX6511UT_ _ _ -T
-40°C to +85°C 6 SOT23-6
MAX6512UT_ _ _ -T
-40°C to +85°C 6 SOT23-6 Open-Drain
MAX6513UT_ _ _ -T
-40°C to +85°C 6 SOT23-6
CMOS
(Active-High)
*These parts are offered in nine standard temperature versions
with a minimum order of 2500 pieces. To complete the suffix information, select an available trip point in degrees centigrade from
the device marking codes table. For example, the
MAX6511UT065-T describes a MAX6511 in a SOT23-6 package
with a +65°C threshold.
( ) ARE FOR MAX6513 SOT23 ONLY.
Typical Operating Circuit appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
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.
1
MAX6511/MAX6512/MAX6513
Features
General Description
The MAX6511/MAX6512/MAX6513 are fully integrated,
remote temperature switches that use an external P-N
junction (typically a diode-connected transistor) as the
sensing element to measure the remote temperature.
These devices assert a logic signal when the temperature crosses a factory-programmed threshold. Available
trip thresholds are from +45°C to +125°C in 10°C increments. Accuracy is within ±3°C (TA = -5°C to +55°C) or
±5°C (TA = -40°C to +85°C). Hysteresis is pin selectable to 5°C or 10°C.
The MAX6511 has an active-low CMOS output and the
MAX6513 has an active-high CMOS output. The
MAX6512 has an open-drain output. The output is
asserted when the temperature exceeds the threshold
value. The active-low open-drain output is intended to
interface with a microprocessor (µP) reset or interrupt
input. The active-high CMOS output can directly drive a
power FET to control a cooling fan.
MAX6511/MAX6512/MAX6513
Low-Cost, Remote SOT Temperature Switches
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (VDD) ...............................................-0.3V to +6V
DXP, DXN, HYST, TOVER (MAX6513),
TOVER (MAX6511/MAX6512) ................-0.3V to (VDD + 0.3V)
TOVER (MAX6513), TOVER (MAX6511)
Output Current ....................................................-1mA/+50mA
DXN Input Current...................................................-1mA/+50mA
Current (all other pins)......................................................±20mA
Continuous Power Dissipation (TA = +70°C)
6-Pin SOT23-6 (derate 9.1mW/°C above +70°C) ........727mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature ......................................................+150°C
Lead Temperature
Vapor Phase (60s) .......................................................+215°C
Infrared (15s) ...............................................................+220°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
(VDD = +3.0V to +5.5V, CS = 2200pF, TA = -40°C to +85°C, TREMOTE = +45°C to +125°C (Note 1), unless otherwise noted. Typical
values are at TA = +25°C.) (Note 2)
PARAMETER
SYMBOL
Supply Voltage Range
VDD
Supply Current
IDD
Temperature Threshold
Accuracy (Note 3)
∆TTH
CONDITIONS
MIN
400
MAX
V
600
µA
-3.0
+3.0
TA = -40°C to +85°C
-5.0
+5.0
HYST = VIL
5
HYST = VIH
10
Response Time
70
Input Voltage High
VIH
Input Voltage Low
VIL
°C
120
VDD 0.2
VOH
MAX6511/MAX6513, IOUT = 1mA
Output Voltage Low
VOL
IOUT = 1mA
ms
V
0.2
Output Voltage High
°C
°C/V
-0.6
THYST
UNITS
5.5
TA = -5°C to +55°C
Power-Supply Sensitivity for
Temperature Trip Point
Temperature Threshold
Hysteresis
TYP
3.0
VDD
- 0.2
V
V
0.2
V
Maximum DXP Source
Current
0.4V ≤ VDXP ≤ 2V,
DXN = GND
270
µA
Minimum DXP Source
Current
0.4V ≤ VDXP ≤ 2V,
DXN = GND
9
µA
Note 1: TREMOTE refers to the temperature of the remote-sensing junction. TA refers to the temperature of the MAX6511/MAX6512/
MAX6513 package.
Note 2: All parameters are 100% production tested at TA = +25°C. Specifications over temperature limits are guaranteed by design.
Note 3: This parameter is guaranteed by design to ±3.5 sigma.
2
_______________________________________________________________________________________
Low-Cost, Remote SOT Temperature Switches
380
360
(NOTE: SUPPLY CURRENT
INCLUDES EXTERNAL
DIODE-CONNECTED
TRANSISTOR)
340
320
300
MAX6511 toc02
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
-1.2
-1.4
14
TEMPERATURE TRIP THRESHOLD ERROR (°C)
400
-1.6
-15
10
35
60
85
AMBIENT TEMPERATURE TA (°C)
8
6
4
2
0
-2
10
0
-0.5
-1.0
-1.5
-2.0
20
30
40
50
60
CS CAPACITANCE (nF)
AMBIENT TEMPERATURE TA (°C)
TEMPERATURE TRIP THRESHOLD
vs. SUPPLY VOLTAGE
0.4
MAX6511 toc05
TEMPERATURE TRIP THRESHOLD ERROR (°C)
0.5
10
0
20 40 60 80 100 120 140
TEMPERATURE TRIP THRESHOLD ERROR
vs. SERIES RESISTANCE
1.0
12
-4
-60 -40 -20 0
MAX6511 toc04
-40
TEMPERATURE TRIP THRESHOLD ERROR (°C)
SUPPLY CURRENT (µA)
420
TEMPERATURE TRIP THRESHOLD ERROR (°C)
MAX6511 toc01
440
TEMPERATURE TRIP THRESHOLD ERROR
vs. CS CAPACITANCE
TEMPERATURE TRIP THRESHOLD ERROR
vs. AMBIENT TEMPERATURE TA
MAX6511 toc03
SUPPLY CURRENT
vs. AMBIENT TEMPERATURE
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
-1.2
-1.4
-1.6
-1.8
0
20 40 60 80 100 120 140 160 180 200
SERIES RESISTANCE (Ω)
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
_______________________________________________________________________________________
3
MAX6511/MAX6512/MAX6513
Typical Operating Characteristics
(VDD = +3.3V, CS = 2200pF, TA = +25°C, unless otherwise noted.)
Low-Cost, Remote SOT Temperature Switches
MAX6511/MAX6512/MAX6513
Pin Description
PIN
NAME
FUNCTION
MAX6511
MAX6512
MAX6513
1
1
VDD
Power-Supply Input, +3.0V to +5.5V. Bypass VDD to GND with a 0.1µF
capacitor.
2
2
GND
Ground
3
3
HYST
Hysteresis Selection. Hysteresis is 10°C for HYST = VDD, 5°C for HYST = GND.
4
—
TOVER
CMOS Active-Low Output (MAX6511) or Open-Drain Active-Low Output
(MAX6512). TOVER goes low when the temperature exceeds the factoryprogrammed temperature threshold. This pin can only sink current in the
MAX6512.
—
4
TOVER
CMOS Active-High Output (MAX6513). TOVER goes high when the temperature
exceeds the factory-programmed temperature threshold.
5
5
DXN
This pin connects to the negative (cathode) terminal of the external P-N sense
junction. DXN must be connected to GND.
6
6
DXP
This pin connects to the positive (anode) terminal of the external P-N sense
junction.
Detailed Description
The MAX6511/MAX6512/MAX6513 fully integrated temperature switches incorporate a precision bandgap reference, a conversion block, a current source, and a
comparator (Figure 1). These devices use an external
P-N junction as the temperature-sensing element. They
steer bias currents through the external diode, measure
the forward voltages, and compute the temperature
using a precision chopper stabilized amplifier.
Resistance values of less than 100Ω in series with the
external sense junction will result in trip-point errors
<1°C. The MAX6511/MAX6512/MAX6513 provide noise
immunity by integration and oversampling of the diode
voltage, but good design practice includes routing the
DXP and DXN lines away from noise sources, such as
high-speed digital lines, switching regulators, inductors, and transformers. The DXP and DXN traces
should be paired together and surrounded by ground
plane whenever possible.
In applications where the temperature changes rapidly,
the measured temperature will be approximately equal
to the average value of the temperature during the
measurement period.
The MAX6512 has an active-low, open-drain output structure that can only sink current. The MAX6511 has an activelow CMOS output structure, and the MAX6513 has an
active-high CMOS output.
The MAX6511/MAX6512/MAX6513 are available with
preset temperature thresholds from +45°C to +125°C in
10°C increments.
DXP
DXN
BANDGAP
TEMPERATURE
CONVERSION
COMPARATOR
VOLTAGE
REFERENCE
Figure 1. Functional Block Diagram
4
_______________________________________________________________________________________
LATCH
TOVER
Low-Cost, Remote SOT Temperature Switches
MANUFACTURER
MODEL NUMBER
Central Semiconductor (USA)
CMPT3904
ON (USA)
MMBT3904
Rohm Semiconductor (Japan)
SST3904
Samsung (Korea)
KST3904-TF
Siemens (Germany)
SMBT3904
Zetex (England)
FMMT3904CT-ND
Note: Transistors must be diode connected (base shorted to
collector).
Hysteresis Input
The HYST pin is a CMOS-compatible input that selects
hysteresis at either a high level (10°C for HYST = VDD)
or a low level (5°C for HYST = GND). Hysteresis prevents the output from chattering when the temperature
is near the trip point. The HYST pin must not float.
The output asserts when the temperature exceeds the
trip point and deasserts when the temperature falls
back below the trip point minus the hysteresis. For
example, if the trip point is 105°C, the output will assert
at 105°C and will not deassert until temperature falls
below 105°C minus the hysteresis (e.g., 95°C if 10°C
hysteresis is chosen) (Figure 2).
Applications Information
Remote-Diode Selection
TRIP TEMPERATURE
TRIP TEMPERATURE HYSTERESIS
TOVER (MAX6511)
TIME
Figure 2. Temperature Trip Threshold Hysteresis
cate the manufacturer has good process controls and
that the devices have consistent Vbe characteristics.
The MAX6511/MAX6512/MAX6513 can also measure
the die temperature of CPUs and other integrated circuits having on-board temperature-sensing diodes.
Use the monitor’s output to reset the µP, assert an interrupt, activate a cooling fan, or trigger an external alarm.
Noise Filtering Capacitors
A quality ceramic capacitor must be connected across
the DXP/DXN inputs to maintain temperature threshold
accuracy by filtering out noise. The capacitor should be
located physically close to the DXP/DXN pins and
should typically have a value of 2200pF. Larger capacitor values can cause temperature measurement errors.
A 50% variation from the recommended capacitor
value can cause up to ±1°C error.
To ensure best accuracy, use a good-quality diodeconnected transistor. Suggested devices are listed in
Table 1. Large power transistors are not recommended. Tight specifications for forward current gain indi-
_______________________________________________________________________________________
5
MAX6511/MAX6512/MAX6513
Table 1. Sensor Transistor Manufacturers
Low-Cost, Remote SOT Temperature Switches
MAX6511/MAX6512/MAX6513
Typical Operating Circuit
3.3V
2µF
VDD
µP
DXP
CS
DXN
HYST
MAX6511
TOVER (TO MICROPROCESSOR FAN
CONTROLLER, SHUTDOWN, ETC.)
Device Marking Codes for SOT23-6 Package
DEVICE
CODE
TEMPERATURE TRIP
THRESHOLD (°C)
DEVICE
CODE
TEMPERATURE TRIP
THRESHOLD (°C)
MAX6511UT045
AAOA
45
MAX6512UT095
AAOO
95
MAX6511UT055
AAOB
55
MAX6512UT105
AAOP
105
MAX6511UT065
AAOC
65
MAX6512UT115
AAOQ
115
MAX6511UT075
AAOD
75
MAX6512UT125
AAOR
125
MAX6511UT085
AAOE
85
MAX6513UT045
AAPD
45
MAX6511UT095
AAOF
95
MAX6513UT055
AAPE
55
MAX6511UT105
AAOG
105
MAX6513UT065
AAPF
65
MAX6511UT115
AAOH
115
MAX6513UT075
AAPG
75
MAX6511UT125
AAOI
125
MAX6513UT085
AAPH
85
MAX6512UT045
AAOJ
45
MAX6513UT095
AAPI
95
MAX6512UT055
AAOK
55
MAX6513UT105
AAPJ
105
MAX6512UT065
AAOL
65
MAX6513UT115
AAPK
115
MAX6512UT075
AAOM
75
MAX6513UT125
AAPL
125
MAX6512UT085
AAON
85
Chip Topography
TRANSISTOR COUNT: 3300
6
_______________________________________________________________________________________
Low-Cost, Remote SOT Temperature Switches
6LSOT.EPS
PACKAGE OUTLINE, SOT-23, 6L
21-0058
F
1
1
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 _____________________ 7
© 2003 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
MAX6511/MAX6512/MAX6513
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.)