19-3183; Rev 3; 4/11
Dual Remote/Local Temperature Sensors with
SMBus Serial Interface
General Description
The MAX6695/MAX6696 are precise, dual-remote, and
local digital temperature sensors. They accurately mea-
sure the temperature of their own die and two remote
diode-connected transistors, and report the tempera-
ture in digital form on a 2-wire serial interface. The
remote diode is typically the emitter-base junction of a
common-collector PNP on a CPU, FPGA, GPU, or ASIC.
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 MAX6695/MAX6696 can func-
tion autonomously with a programmable conversion
rate, which allows control of supply current and temper-
ature update rate to match system needs. For conver-
sion rates of 2Hz or less, the temperature is
represented as 10 bits + sign with a resolution of
+0.125°C. When the conversion rate is 4Hz, output data
is 7 bits + sign with a resolution of +1°C. The MAX6695/
MAX6696 also include an SMBus timeout feature to
enhance system reliability.
Remote temperature sensing accuracy is ±1.5°C be-
tween +60°C and +100°C with no calibration needed.
The MAX6695/MAX6696 measure temperatures from
-40°C to +125°C. In addition to the SMBus
ALERT
out-
put, the MAX6695/MAX6696 feature two overtempera-
ture limit indicators (OT1 and
OT2),
which are active
only while the temperature is above the corresponding
programmable temperature limits. The
OT1
and
OT2
outputs are typically used for fan control, clock throt-
tling, or system shutdown.
The MAX6695 has a fixed SMBus address. The
MAX6696 has nine different pin-selectable SMBus
addresses. The MAX6695 is available in a 10-pin
μMAX
®
and the MAX6696 is available in a 16-pin QSOP
package. Both operate throughout the -40°C to +125°C
temperature range.
♦
Measure One Local and Two Remote
Temperatures
♦
11-Bit, +0.125°C Resolution
♦
High Accuracy ±1.5°C (max) from +60°C to +100°C
(Remote)
♦
ACPI Compliant
♦
Programmable Under/Overtemperature Alarms
♦
Programmable Conversion Rate
♦
Three Alarm Outputs:
ALERT, OT1,
and
OT2
♦
SMBus/I
2
C-Compatible Interface
♦
Compatible with 65nm Process Technology
(Y Versions)
Features
MAX6695/MAX6696
Ordering Information
PART
MAX6695AUB+
MAX6695YAUB+
MAX6696AEE+
MAX6696YAEE+
TEMP RANGE
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
-40°C to +125°C
PIN-PACKAGE
10 μMAX
10 μMAX
16 QSOP
16 QSOP
Devices are also available in tape-and-reel packages. Specify
tape and reel by adding “T” to the part number when ordering.
+Denotes
a lead(Pb)-free/RoHS-compliant package.
Typical Operating Circuit
0.1μF
47Ω
+3.3V
10kΩ
EACH
CPU
DXP1
V
CC
SMBDATA
SMBCLK
DATA
CLOCK
INTERRUPT
TO
μP
TO CLOCK
THROTTLING
TO SYSTEM
SHUTDOWN
Applications
Notebook Computers
Desktop Computers
Servers
Workstations
Test and Measurement Equipment
GRAPHICS
PROCESSOR
DXP2
DXN
MAX6695
ALERT
OT1
OT2
GND
Typical Operating Circuits continued at end of data sheet.
μMAX is a registered trademark of Maxim Integrated Products, Inc.
Pin Configurations appear at end of data sheet.
1
________________________________________________________________
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.
Dual Remote/Local Temperature Sensors with
SMBus Serial Interface
MAX6695/MAX6696
ABSOLUTE MAXIMUM RATINGS
V
CC
...........................................................................-0.3V to +6V
DXP1, DXP2................................................-0.3V to (V
CC
+ 0.3V)
DXN ......................................................................-0.3V to +0.8V
SMBCLK, SMBDATA,
ALERT
...................................-0.3V to +6V
RESET,
STBY,
ADD0, ADD1,
OT1, OT2
...................-0.3V to +6V
SMBDATA Current .................................................1mA to 50mA
DXN Current ......................................................................±1mA
Continuous Power Dissipation (T
A
= +70°C)
10-Pin μMAX (derate 6.9mW/°C above +70°C) ........555.6mW
16-Pin QSOP (derate 8.3mW/°C above +70°C) .......666.7mW
Operating Temperature Range .........................-40°C to +125°C
Junction Temperature .....................................................+150°C
Storage Temperature Range ............................-65°C to +150°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
(V
CC
= +3.0V to +3.6V, T
A
= 0°C to +125°C, unless otherwise noted. Typical values are at V
CC
= +3.3V and T
A
= +25°C)
PARAMETER
Supply Voltage
Standby Supply Current
Operating Current
Average Operating Current
SYMBOL
V
CC
SMBus static, ADC in idle state
Interface inactive, ADC active
Conversion rate = 0.125Hz
Conversion rate = 1Hz
Conversion rate = 4Hz
T
RJ
= +25°C to +100°C
(T
A
= +45°C to +85°C)
Remote Temperature Error
(Note 1)
T
RJ
= 0°C to +125°C (T
A
= +25°C to +100°C)
T
RJ
= -40°C to +125°C (T
A
= 0°C to +125°C)
T
RJ
= -40°C to +125°C (T
A
= -40°C)
T
A
= +45°C to +85°C
Local Temperature Error
T
A
= +25°C to +100°C
T
A
= 0°C to +125°C
T
A
= -40°C to +125°C
T
A
= +45°C to +85°C
Local Temperature Error
(MAX6695Y/MAX6696Y)
Power-On Reset Threshold
POR Threshold Hysteresis
Undervoltage Lockout Threshold
Undervoltage Lockout Hysteresis
Channel 1 rate 4Hz, channel 2 / local rate
2Hz (conversion rate register 05h)
Channel 1 rate 8Hz, channel 2 / local rate
4Hz (conversion rate register 06h)
Remote-Diode Source Current
I
RJ
High level
Low level
112.5
56.25
80
8
UVLO
Falling edge of V
CC
disables ADC
2.2
T
A
= +25°C to +100°C
T
A
= 0°C to +125°C
T
A
= -40°C to +125°C
V
CC
, falling edge (Note 2)
1.3
-2.0
-3.0
-4.5
+3.0
-3.8
-4.0
-4.2
-4.4
1.45
500
2.8
90
125
62.5
100
10
137.5
ms
68.75
120
12
μA
2.95
1.6
V
mV
V
mV
°C
-1.5
-3.0
-5.0
+3.0
+2.0
+3.0
+4.5
°C
0.5
35
250
500
CONDITIONS
MIN
3.0
TYP
MAX
3.6
10
1
70
500
1000
+1.5
+3.0
+5.0
°C
μA
UNITS
V
μA
mA
Conversion Time
2
_______________________________________________________________________________________
Dual Remote/Local Temperature Sensors with
SMBus Serial Interface
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +3.0V to +3.6V, T
A
= 0°C to +125°C, unless otherwise noted. Typical values are at V
CC
= +3.3V and T
A
= +25°C)
PARAMETER
ALERT, OT1, OT2
Output Low Sink Current
Output High Leakage Current
INPUT PIN, ADD0, ADD1 (MAX6696)
Logic Input Low Voltage
Logic Input High Voltage
Logic Input Low Voltage
Logic Input High Voltage
Input 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
Repeat START Condition Setup
Time
START Condition Hold Time
STOP Condition Setup Time
Clock Low Period
Clock High Period
Data Setup Time
Data Hold Time
SMB Rise Time
SMB Fall Time
SMBus Timeout
V
IL
V
IH
V
IL
V
IH
I
LEAK
V
IL
V
IH
I
LEAK
I
OL
C
IN
f
SCL
t
BUF
t
SU:STA
t
HD:STA
t
SU:STO
t
LOW
t
HIGH
t
SU:DAT
t
HD:DAT
t
R
t
F
SMBDATA low period for interface reset
20
30
90% of SMBCLK to 90% of SMBDATA
10% of SMBDATA to 90% of SMBCLK
90% of SMBCLK to 90% of SMBDATA
10% to 10%
90% to 90%
10
4.7
4.7
4
4
4
4.7
250
300
1
300
40
V
IN
= GND or V
CC
V
OL
= 0.6V
5
100
2.1
±1
6
2.1
-1
+1
0.8
2.9
0.8
0.3
V
V
V
V
μA
V
V
μA
mA
pF
kHz
μs
μs
μs
μs
μs
μs
ns
ns
μs
ns
ms
V
OL
= 0.4V
V
OH
= 3.6V
6
1
mA
μA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6695/MAX6696
INPUT PIN, RESET,
STBY
(MAX6696)
SMBus INTERFACE (SMBCLK, SMBDATA,
STBY)
SMBus-COMPATIBLE TIMING
(Figures 4 and 5) (Note 2)
Note 1:
Based on diode ideality factor of 1.008.
Note 2:
Specifications are guaranteed by design, not production tested.
_______________________________________________________________________________________
3
Dual Remote/Local Temperature Sensors with
SMBus Serial Interface
MAX6695/MAX6696
Typical Operating Characteristics
(V
CC
= 3.3V, T
A
= +25°C, unless otherwise noted.)
STANDBY SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX6695 toc01
AVERAGE OPERATING SUPPLY CURRENT
vs. CONVERSION RATE CONTROL REGISTER VALUE
MAX6695 toc02
TEMPERATURE ERROR
vs. REMOTE-DIODE TEMPERATURE
4
TEMPERATURE ERROR (°C)
3
2
1
0
-1
-2
-3
-4
REMOTE CHANNEL2
REMOTE CHANNEL1
MAX6695 toc03
6
STANDBY SUPPLY CURRENT (μA)
5
4
3
2
1
0
3.0
3.1
3.2
3.3
3.4
3.5
600
OPERATING SUPPLY CURRENT (μA)
500
400
300
200
100
0
5
-5
0
1
2
3
4
5
6
7
-50
-25
0
25
50
75
100
125
CONVERSION RATE CONTROL REGISTER VALUE (hex)
REMOTE TEMPERATURE (°C)
3.6
SUPPLY VOLTAGE (V)
LOCAL TEMPERATURE ERROR
vs. DIE TEMPERATURE
MAX6695 toc04
TEMPERATURE ERROR
vs. DXP-DXN CAPACITANCE
MAX6695 toc05
TEMPERATURE ERROR
vs. DIFFERENTIAL NOISE FREQUENCY
V
IN
= 10mV
P-P
2
TEMPERATURE ERROR (°C)
1
0
REMOTE CHANNEL1
-1
-2
-3
REMOTE CHANNEL2
MAX6695 toc06
5
4
TEMPERATURE ERROR (°C)
3
2
1
0
-1
-2
-3
-4
-5
-50
-25
0
25
50
75
100
3
2
TEMPERATURE ERROR (°C)
1
0
-1
-2
-3
REMOTE CHANNEL1
REMOTE CHANNEL2
3
125
1
10
DXP-DXN CAPACITANCE (nF)
100
0.001
0.01
0.1
1
10
100
DIE TEMPERATURE (°C)
FREQUENCY (MHz)
REMOTE TEMPERATURE ERROR
vs. POWER-SUPPLY NOISE FREQUENCY
MAX6695 toc07a
LOCAL TEMPERATURE ERROR
vs. POWER-SUPPLY NOISE FREQUENCY
MAX6695 toc07b
TEMPERATURE ERROR
vs. COMMON-MODE NOISE FREQUENCY
10mV
P-P
2
TEMPERATURE ERROR (°C)
REMOTE CHANNEL2
1
0
REMOTE CHANNEL1
-1
-2
-3
MAX6695 toc08
3
100mV
P-P
2
TEMPERATURE ERROR (°C)
REMOTE CHANNEL2
1
0
-1
-2
-3
0.001
0.01
0.1
1
10
REMOTE CHANNEL1
3
100mV
P-P
2
TEMPERATURE ERROR (°C)
1
0
-1
-2
-3
3
100
0.001
0.01
0.1
1
10
100
0.001
0.01
0.1
1
10
100
FREQUENCY (MHz)
FREQUENCY (MHz)
FREQUENCY (Hz)
4
_______________________________________________________________________________________
Dual Remote/Local Temperature Sensors with
SMBus Serial Interface
Pin Description
PIN
MAX6695
1
MAX6696
2
NAME
FUNCTION
Supply Voltage Input, +3V to +3.6V. Bypass to GND with a 0.1μF capacitor. A 47
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 1. DO NOT LEAVE DXP1 UNCONNECTED; connect DXP1 to DXN if no
remote diode is used. Place a 2200pF capacitor between DXP1 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.
Combined Remote-Diode Current Source and A/D Positive Input for Remote-Diode
Channel 2. DO NOT LEAVE DXP2 UNCONNECTED; connect DXP2 to DXN if no
remote diode is used. Place a 2200pF capacitor between DXP2 and DXN for noise
filtering.
Overtemperature Active-Low Output, Open Drain.
OT1
is asserted low only when
the temperature is above the programmed OT1 threshold.
Ground
SMBus Serial-Clock Input
SMBus Alert (Interrupt) Active-Low Output, Open-Drain. Asserts when temperature
exceeds user-set limits (high or low temperature) or when a remote sensor opens.
Stays asserted until acknowledged by either reading the status register or by
successfully responding to an alert response address. See the
ALERT Interrupts
section.
SMBus Serial-Data Input/Output, Open Drain
Overtemperature Active-Low Output, Open Drain.
OT2
is asserted low only when
temperature is above the programmed OT2 threshold.
No Connect
SMBus Slave Address Select Input (Table 10). ADD0 and ADD1 are sampled upon
power-up.
Reset Input. Drive RESET high to set all registers to their default values (POR state).
Pull RESET low for normal operation.
SMBus Slave Address Select Input (Table 10). ADD0 and ADD1 are sampled upon
power-up.
Hardware Standby Input. Pull
STBY
low to put the device into standby mode.
All registers’ data are maintained.
MAX6695/MAX6696
V
CC
2
3
DXP1
3
4
DXN
4
5
DXP2
5
6
7
10
8
9
OT1
GND
SMBCLK
8
11
ALERT
9
10
—
—
—
—
—
12
13
1, 16
6
7
14
15
SMBDATA
OT2
N.C.
ADD1
RESET
ADD0
STBY
_______________________________________________________________________________________
5
