19-2034; Rev 5; 10/10
±1°C, SMBus-Compatible Remote/Local Temperature
Sensors with Overtemperature Alarms
General Description
The MAX6657/MAX6658/MAX6659 are precise, two-
channel digital temperature sensors. Each accurately
measures the temperature of its own die and one
remote PN junction, and reports the temperature in digi-
tal form on a 2-wire serial interface. The remote junction
can be a diode-connected transistor like the low-cost
NPN type 2N3904 or 2N3906 PNP type. The remote
junction can also be a common-collector PNP, such as
a substrate PNP of a microprocessor.
The 2-wire serial interface accepts standard System
Management Bus (SMBus™) commands such as Write
Byte, Read Byte, Send Byte, and Receive Byte to read
the temperature data and program the alarm thresholds
and conversion rate. The MAX6657/MAX6658/
MAX6659 can function autonomously with a program-
mable conversion rate, which allows the control of sup-
ply current and temperature update rate to match
system needs. For conversion rates of 4Hz or less, the
temperature is represented in extended mode as 10
bits + sign with a resolution of 0.125°C. When the con-
version rate is faster than 4Hz, output data is 7 bits +
sign with a resolution of 1°C. The MAX6657/
MAX6658/MAX6659 also include an SMBus timeout
feature to enhance system reliability.
Remote accuracy is ±1°C between +60°C and +100°C
with no calibration needed. The MAX6657 measures
temperatures from 0°C to +125°C and the MAX6658/
MAX6659 from -55°C to +125°C. The MAX6659 has the
added benefit of being able to select one of three
addresses through an address pin, and a second over-
temperature alarm pin for greater system reliability.
o
11-Bit, +0.125°C Resolution
o
High Accuracy ±1°C (max) from +60°C to +100°C
(Remote)
o
No Calibration Required
o
Programmable Under/Overtemperature Alarms
o
Programmable Conversion Rate
(0.0625Hz to 16Hz)
o
SMBus/I
2
C-Compatible Interface
o
Two Alarm Outputs:
ALERT
and
OVERT1
(MAX6657 and MAX6658)
o
Three Alarm Outputs:
ALERT, OVERT1,
and
OVERT2
(MAX6659)
o
Compatible with 65nm Process Technology
(Y Versions)
Features
o
Dual Channel Measures Remote and Local
Temperature
MAX6657/MAX6658/MAX6659
Ordering Information
PART
MAX6657MSA
MAX6657MSA+
MAX6657MSA-T
MAX6657MSA+T
MAX6657YMSA+
MEASURED TEMP
RANGE
0°C to +125°C
0°C to +125°C
0°C to +125°C
0°C to +125°C
0°C to +125°C
PIN-PACKAGE
8 SO
8 SO
8 SO
8 SO
8 SO
Applications
Desktop Computers
Notebook Computers
Servers
Workstations
MAX6657YMSA+T
0°C to +125°C
8 SO
Note:
All devices are specified over the -55°C to +125°C oper-
ating temperature range.
+Denotes
a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
Ordering Information continued at end of data sheet.
Pin Configurations
TOP VIEW
V
CC
1
N.C. 2
DXP 3
DXN 4
ADD 5
OVERT1 6
GND 7
GND 8
16 N.C.
15 STBY
14 SMBCLK
V
CC
1
DXP 2
DXN 3
OVERT1 4
8 SMBCLK
7 SMBDATA
Typical Operating Circuit appears at the end of the data
sheet.
MAX6659
13 N.C.
12 SMBDATA
11 N.C.
10 OVERT2
9 ALERT
MAX6657
MAX6658
6 ALERT
5 GND
SO
SMBus is a trademark of Intel Corp.
QSOP
________________________________________________________________
Maxim Integrated Products
1
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°C, SMBus-Compatible Remote/Local Temperature
Sensors with Overtemperature Alarms
MAX6657/MAX6658/MAX6659
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND.)
V
CC
..........................................................................-0.3V to +6V
DXP ............................................................-0.3V to (V
CC
+ 0.3V)
DXN ......................................................................-0.3V to +0.8V
SMBCLK, SMBDATA,
ALERT, OVERT1,
OVERT2
..............................................................-0.3V to +6V
SMBDATA,
ALERT, OVERT1, OVERT2
Current ..........................................................-1mA to +50mA
DXN Current ......................................................................±1mA
Continuous Power Dissipation (T
A
= +70°C)
8-Pin SO (derate 5.9mW/°C above +70°C) .................471mW
16-Pin QSOP (derate 8.3mW/°C above +70°C) ..........664mW
Junction Temperature .....................................................+150°C
Storage Temperature Range ............................-65°C to +150°C
Lead Temperature (soldering, 10s) ................................+300°C
Soldering Temperature (reflow)
Lead(Pb)-free ..............................................................+260°C
Containing lead(Pb) ....................................................+240°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
(V
CC
= +3.0V to +5.5V, T
A
= 0°C to +125°C, unless otherwise specified. Typical values are at V
CC
= +3.3V and T
A
= +25°C.)
PARAMETER
Temperature Resolution,
Legacy Mode
Temperature Resolution,
Extended Mode
T
RJ
= +60°C to +100°C, V
CC
= +3.3V
(Note 1)
T
RJ
= 0°C to +100°C, V
CC
= +3.3V (Note 1)
T
RJ
= 0°C to +125°C, V
CC
= +3.3V (Note 1)
Local Temperature Error
(MAX6657)
T
A
= +60°C to +100°C, V
CC
= +3.3V
T
A
= 0°C to +100°C, V
CC
= +3.3V
T
A
= 0°C to +125°C, V
CC
= +3.3V
Remote Temperature Error
(MAX6658/MAX6659/
MAX6658Y/MAX6659Y)
T
RJ
= +60°C to +100°C, V
CC
= +3.3V
(Note 1)
T
RJ
= 0°C to +100°C, V
CC
= +3.3V (Note 1)
T
RJ
= -55°C to +125°C, V
CC
= +3.3V (Note 1)
Local Temperature Error
(MAX6658/MAX6659)
T
A
= +60°C to +100°C, V
CC
= +3.3V
T
A
= 0°C to +100°C, V
CC
= +3.3V
T
A
= -55°C to +125°C, V
CC
= +3.3V (Note 2)
Local Temperature Error
(MAX665_Y)
Line Regulation
Supply Voltage Range
Undervoltage Lockout Threshold
Undervoltage Lockout Hysteresis
Power-On Reset (POR) Threshold
POR Threshold Hysteresis
Standby Supply Current
Operating Current
SMBus static
During conversion
V
CC
, falling edge
1.5
V
CC
UVLO
Falling edge of V
CC
disables ADC
T
A
= +60°C to +100°C, V
CC
= +3.3V
T
A
= 0°C to +100°C, V
CC
= +3.3V
T
A
= 0°C to +125°C, V
CC
= +3.3V
3.0V
≤
V
CC
≤
5.5V
3.0
2.60
2.80
90
2.0
90
3
0.5
10
1.0
2.5
SYMBOL
CONDITIONS
MIN
1
8
0.125
11
-1.0
-3.0
-5.0
-2.0
-3.0
-5.0
-1.0
-3.0
-5.0
-2.0
-3.0
-5.0
-3.8
-4.0
-4.4
0.2
0.6
5.5
2.95
m°C/V
V
V
mV
V
mV
µA
mA
°C
+1.0
+3.0
+5.0
+2.0
+3.0
+5.0
1.0
3.0
+5.0
+2.0
+3.0
+5.0
°C
°C
°C
°C
TYP
MAX
UNITS
°C
Bits
°C
Bits
Remote Temperature Error
(MAX6657, MAX6657Y)
2
_______________________________________________________________________________________
±1°C, SMBus-Compatible Remote/Local Temperature
Sensors with Overtemperature Alarms
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +3.0V to +5.5V, T
A
= 0°C to +125°C, unless otherwise specified. Typical values are at V
CC
= +3.3V and T
A
= +25°C.)
PARAMETER
Average Operating Current
Conversion Time
Conversion Timing Error
DXP and DXN Leakage Current
Remote-Diode Source Current
(ALERT,
OVERT)
Output Low Sink Current
Output High Leakage Current
Logic Input Low Voltage
Logic Input High Voltage
Input Leakage Current
Output Low Sink Current
Input Capacitance
Serial-Clock Frequency
Bus Free Time Between STOP
and START Condition
START Condition Setup Time
Repeat START Condition Setup
Time
START Condition Hold Time
STOP Condition Setup Time
Clock Low Period
Clock High Period
Data Setup Time
Receive SCL/SDA Rise Time
Receive SCL/SDA Fall Time
Pulse Width of Spike Suppressed
SMBus Timeout
t
SU:STA
t
HD:STA
t
SU:STO
t
LOW
t
HIGH
t
HD:DAT
t
R
t
F
t
SP
SMBDATA low period for interface reset
0
25
37
90% to 90%
10% of SMBDATA to 90% of SMBCLK
90% of SMBCLK to 90% of SMBDATA
10% to 10%
90% to 90%
(Note 6)
V
IL
V
IH
I
LEAK
I
OL
C
IN
f
SCL
t
BUF
(Note 5)
4.7
4.7
50
4
4
4.7
4
0
1
300
50
45
V
CC
= +3.0V
V
CC
= +5.5V
V
IN
= V
GND
or V
CC
V
OL
= 0.6V
6
5
100
2.2
2.4
±1
V
OL
= 0.4V
V
OL
= 0.6V
V
OH
= 5.5V
1
6
1
0.8
mA
µA
V
V
µA
mA
pF
kHz
µs
µs
ns
µs
µs
µs
µs
µs
µs
ns
ns
ms
I
RJ
In standby mode
High level
Low level
80
8
100
10
t
CONV
SYMBOL
2 conversions/s
From stop bit to conversion completed
(Note 4)
95
CONDITIONS
0.25 conversions/s
MIN
TYP
40
150
125
MAX
70
250
156
±25
100
120
12
UNITS
µA
ms
%
nA
µA
MAX6657/MAX6658/MAX6659
SMBus-COMPATIBLE INTERFACE (SMBCLK, SMBDATA,
STBY)
SMBus-COMPATIBLE TIMING
(Note 4)
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
T
A
= +25°C to +85°C.
If both the local and the remote junction are below T
A
= -20°C, then V
CC
> 3.15V.
For conversion rates of 4Hz or slower, the conversion time doubles.
Timing specifications guaranteed by design.
The serial interface resets when SMBCLK is low for more than t
TIMEOUT
.
A transition must internally provide at least a hold time to bridge the undefined region (300ns max) of SMBCLK's falling edge.
_______________________________________________________________________________________
3
±1°C, SMBus-Compatible Remote/Local Temperature
Sensors with Overtemperature Alarms
MAX6657/MAX6658/MAX6659
Typical Operating Characteristics
(V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted.)
MAX6659
REMOTE TEMPERATURE ERROR
vs. REMOTE-DIODE TEMPERATURE
MAX6657 toc02
MAX6657 toc03
STANDBY SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX6657 toc01
OPERATING SUPPLY CURRENT
vs. CONVERSION RATE
600
8Hz AND 16Hz ARE 1°C RESOLUTION
OPERATING SUPPLY CURRENT (µA)
3
2
TEMPERATURE ERROR (°C)
1
0
-1
-2
4.5
STANDBY SUPPLY CURRENT (µA)
4.0
400
3.5
200
3.0
FAIRCHILD 2N3906
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
0
0.063 0.125 0.25 0.5
1
2
4
8
16
CONVERSION RATE (Hz)
-3
-55
-30
-5
20
45
70
95
120
TEMPERATURE (°C)
LOCAL TEMPERATURE ERROR
vs. DIE TEMPERATURE
MAX6657 toc04
TEMPERATURE ERROR vs.
POWER-SUPPLY NOISE FREQUENCY
MAX6657 toc05
TEMPERATURE ERROR vs.
COMMON-MODE NOISE FREQUENCY
MAX6657 toc06
3
2
TEMPERATURE ERROR (°C)
1
0
-1
-2
-3
-55
-30
-5
20
45
70
95
120
TEMPERATURE (°C)
1
1
TEMPERATURE ERROR (°C)
0
TEMPERATURE ERROR (°C)
0
-1
V
IN
= SQUARE WAVE APPLIED TO V
CC
WITH NO 0.1µF V
CC
CAPACITOR
-1
-2
-2
V
IN
= AC-COUPLED TO DXN
V
IN
= 100mVp-p
1k
100k
FREQUENCY (Hz)
10M
1G
-3
10k
100k
1M
FREQUENCY (Hz)
10M
100M
-3
0.01k
TEMPERATURE ERROR vs.
DIFFERENTIAL-MODE NOISE FREQUENCY
MAX6657 toc07
TEMPERATURE ERROR vs.
DXP-DXN CAPACITANCE
MAX6657 toc08
1
0
TEMPERATURE ERROR (°C)
0
TEMPERATURE ERROR (°C)
10M
100M
-1
-2
-1
V
IN
= 10mV
P-P
SQUARE WAVE
APPLIED TO DXP-DXN
-3
-2
-4
-3
10k
100k
1M
FREQUENCY (Hz)
-5
0
10 20 30 40 50 60 70 80 90 100
DXP-DXN CAPACITANCE (nF)
4
_______________________________________________________________________________________
±1°C, SMBus-Compatible Remote/Local Temperature
Sensors with Overtemperature Alarms
Pin Description
PIN
MAX6657
MAX6658
1
MAX6659
NAME
FUNCTION
MAX6657/MAX6658/MAX6659
1
V
CC
Supply Voltage Input, +3V to +5.5V. Bypass to GND with a 0.1µF capacitor. A 200Ω
series resistor is recommended but not required for additional noise filtering. See
Typical Operating Circuit.
Combined Remote-Diode Current Source and A/D Positive Input for Remote-Diode
Channel.
DO NOT LEAVE DXP UNCONNECTED;
connect DXP to DXN if no remote
diode is used. Place a 2200pF capacitor between DXP and DXN for noise filtering.
Combined Remote-Diode Current Sink and A/D Negative Input. DXN is internally
biased to one diode drop above ground.
Overtemperature Active-Low Output, Open-Drain. Output is logic low only when
temperature is above the software programmed threshold.
Ground
SMBus Alert (Interrupt) Active-Low Output, Open-Drain. Asserts when temperature
exceeds user-set limits (high or low temperature). Stays asserted until acknowledged
by either reading the Status register or by successfully responding to an Alert
Response address. See
ALERT
Interrupts.
SMBus Serial-Data Input/Output, Open-Drain
SMBus Serial-Clock Input
SMBus Address-Select Pin. The MAX6659 is set to one of three available addresses
(connect to V
CC
, GND, or leave open). See
Slave Addresses
section.
Overtemperature Active-Low Output, Open-Drain. Output is logic low only when
temperature is above the software programmed threshold.
Hardware Standby Input. Temperature and comparison threshold data are retained in
standby mode. If
STBY
is low, the IC is put into standby mode.
Not internally connected. Do not make connections to these pins.
2
3
DXP
3
4
5
4
6
7, 8
DXN
OVERT1
GND
6
9
ALERT
7
8
—
—
—
—
12
14
5
10
15
2, 11, 13, 16
SMBDATA
SMBCLK
ADD
OVERT2
STBY
N.C.
_______________________________________________________________________________________
5