MAX6694TE9A+ [MAXIM]
Serial Switch/Digital Sensor, 11 Bit(s), 4Cel, BICMOS, Square, 16 Pin, Surface Mount, 5 X 5, LEAD FREE, MO-153AB, TQFN, 16 PIN;
| 型号： | MAX6694TE9A+ |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Serial Switch/Digital Sensor, 11 Bit(s), 4Cel, BICMOS, Square, 16 Pin, Surface Mount, 5 X 5, LEAD FREE, MO-153AB, TQFN, 16 PIN 信息通信管理 输出元件 传感器 换能器 |
| 文件： | 总18页 (文件大小：197K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-4097; Rev 0; 4/08
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
General Description
Features
The MAX6694 precision multichannel temperature sen-
sor monitors its own temperature and the temperatures
of up to four external diode-connected transistors. All
temperature channels have programmable alert thresh-
olds. Channels 1 and 4 also have programmable
overtemperature thresholds. When the measured tem-
perature of a channel exceeds the respective thresh-
old, a status bit is set in one of the status registers. Two
open-drain outputs, OVERT and ALERT, assert corre-
sponding to these bits in the status register.
o Four Thermal-Diode Inputs
o Beta Compensation (Channel 1)
o Local Temperature Sensor
o 1.5°C Remote Temperature Accuracy (+60°C to
+100°C)
o Temperature Monitoring Begins at POR for Fail-
Safe System Protection
o ALERT and OVERT Outputs for Interrupts,
Throttling, and Shutdown
The 2-wire serial interface supports the standard system
management bus (SMBus™) protocols: write byte, read
byte, send byte, and receive byte for reading the tem-
perature data and programming the alarm thresholds.
o STBY Input for Hardware Standby Mode
o Small, 16-Pin TSSOP and TQFN Packages
o 2-Wire SMBus Interface
The MAX6694 is specified for a -40°C to +125°C oper-
ating temperature range and is available in 16-pin
TSSOP and 5mm x 5mm thin QFN packages.
Applications
Ordering Information
Desktop Computers
Notebook Computers
Workstations
PART
TEMP RANGE
-40°C to +125°C
-40°C to +125°C
PIN-PACKAGE
MAX6694UE9A+
MAX6694TE9A+
16 TSSOP
16 TQFN-EP*
+Denotes a lead-free package.
*EP = Exposed pad.
Servers
Note: Slave address is 1001 101.
SMBus is a trademark of Intel Corp.
Pin Configurations appear at end of data sheet.
Typical Application Circuit
+3.3V
CPU
4.7kΩ
EACH
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
DXP1
DXN1
DXP2
DXN2
DXP3
DXN3
DXP4
DXN4
GND
SMBCLK
SMBDATA
ALERT
100pF
100pF
100pF
100pF
CLK
DATA
MAX6694
INTERRUPT
TO µP
V
CC
0.1µF
OVERT
TO SYSTEM
SHUTDOWN
N.C.
STBY
________________________________________________________________ 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.
5-Channel Precision Temperature Monitor
with Beta Compensation
ABSOLUTE MAXIMUM RATINGS
Junction-to-Case Thermal Resistance (θ ) (Note 1)
V
, SMBCLK, SMBDATA, ALERT, OVERT,
JC
CC
16-Pin TQFN...................................................................2°C/W
STBY to GND ....................................................-0.3V to +6.0V
DXP_ to GND..............................................-0.3V to (V + 0.3V)
16-Pin TSSOP...............................................................27°C/W
CC
Junction-to-Ambient Thermal Resistance (θ ) (Note 1)
DXN_ to GND ........................................................-0.3V to +0.8V
SMBDATA, ALERT, OVERT Current....................-1mA to +50mA
DXIV_ Current..................................................................... 1mA
JA
16-Pin TQFN.................................................................30°C/W
16-Pin TSSOP...............................................................90°C/W
ESD Protection (all pins, Human Body Model) .................... 2kV
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
Continuous Power Dissipation (T = +70°C)
A
16-Pin TQFN, 5mm x 5mm
(derate 33.3mW/°C above +70°C)............................2666.7mW
16-Pin TSSOP
(derate 11.1mW/°C above +70°C)............................888.9mW
MAX694
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-
layer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
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
= +3.0V to +3.6V, V
= V , T = -40°C to +125°C, unless otherwise noted. Typical values are at V
= +3.3V and T =
CC A
CC
STBY
CC
A
+25°C.) (Note 2)
PARAMETER
Supply Voltage
SYMBOL
CONDITIONS
MIN
TYP
MAX
3.6
UNITS
V
3.0
V
CC
SS
Software Standby Supply Current
Operating Current
I
SMBus static
3
500
11
8
10
µA
µA
I
During conversion (Note 3)
Channel 1 only
2000
CC
Temperature Resolution
Bits
°C
°C
°C
°C
°C
°C
Other diode channels
T
A
T
A
T
A
T
A
T
A
T
A
T
A
T
A
T
A
T
A
T
A
T
A
= T = +60°C to +100°C
-1.5
-2.375
-2
+1.5
+2.375
+2
RJ
3 σ Temperature Accuracy
(Remote Channel 1)
V
= 3.3V,
CC
ß = 0.5
= T = 0°C to +125°C
RJ
= T = +60°C to +100°C
RJ
3 σ Temperature Accuracy
(Remote Channels 2–6)
V
V
= 3.3V
CC
= T = 0°C to +125°C
RJ
-2.5
-2
+2.5
+2
= +60°C to +100°C
= 0°C to +125°C
3 σ Temperature Accuracy
(Local)
= 3.3V
= 3.3V,
CC
-2.5
-3
+2.5
+3
= T = +60°C to +100°C
RJ
6 σ Temperature Accuracy
(Remote Channel 1)
V
CC
ß = 0.5
= T = 0°C to +125°C
-4
+4
RJ
= T = +60°C to +100°C
-3
+3
RJ
6 σ Temperature Accuracy
(Remote Channels 2–6)
V
V
= 3.3V
= 3.3V
CC
CC
= T = 0°C to +125°C
RJ
-3.5
-2.5
-3
+3.5
+2.5
+3
= +60°C to +100°C
= 0°C to +125°C
6 σ Temperature Accuracy
(Local)
Supply Sensitivity of Temperature
Accuracy
0.2
250
125
oC/V
ms
Remote Channel 1 Conversion Time
t
190
95
312
156
CONV1
Remote Channels 2, 3, 4
Conversion Time
t
ms
CONV_
2
_______________________________________________________________________________________
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
ELECTRICAL CHARACTERISTICS (continued)
(V
= +3.0V to +3.6V, V
= V , T = -40°C to +125°C, unless otherwise noted. Typical values are at V
= +3.3V and T =
CC A
CC
STBY
CC
A
+25°C.) (Note 2)
PARAMETER
SYMBOL
CONDITIONS
High level, channel 1
MIN
TYP
500
20
MAX
UNITS
Low level, channel 1
Remote-Diode Source Current
I
µA
RJ
High level, channels 2, 3, 4
Low level, channels 2, 3, 4
80
8
100
10
120
12
Undervoltage-Lockout Threshold
Undervoltage-Lockout Hysteresis
Power-On-Reset (POR) Threshold
POR Threshold Hysteresis
ALERT, OVERT
UVLO
Falling edge of V disables ADC
2.30
2.80
90
2.95
V
CC
mV
V
V
falling edge
1.2
2.0
90
2.25
CC
mV
I
I
= 1mA
= 6mA
0.3
0.5
1
SINK
Output Low Voltage
V
V
OL
SINK
Output Leakage Current
µA
SMBus INTERFACE (SMBCLK, SMBDATA), STBY
Logic Input Low Voltage
Logic Input High Voltage
Input Leakage Current
Output Low Voltage
V
0.8
V
V
IL
V
V
= 3.0V
2.2
-1
IH
CC
+1
µA
V
V
I
= 6mA
0.3
OL
SINK
Input Capacitance
C
5
pF
IN
SMBus-COMPATIBLE TIMING (Figures 3 and 4) (Note 4)
Serial-Clock Frequency
f
(Note 5)
400
kHz
µs
SMBCLK
f
f
f
f
= 100kHz
= 400kHz
= 100kHz
= 400kHz
4.7
1.6
4.7
0.6
SMBCLK
SMBCLK
SMBCLK
SMBCLK
Bus Free Time Between STOP
and START Condition
t
BUF
START Condition Setup Time
µs
90% of SMBCLK to 90% of SMBDATA,
= 100kHz
0.6
f
SMBCLK
Repeat START Condition Setup
Time
t
µs
µs
µs
SU:STA
HD:STA
SU:STO
90% of SMBCLK to 90% of SMBDATA,
= 400kHz
0.6
0.6
4
f
SMBCLK
START Condition Hold Time
STOP Condition Setup Time
t
t
10% of SMBDATA to 90% of SMBCLK
90% of SMBCLK to 90% of SMBDATA,
f
= 100kHz
SMBCLK
90% of SMBCLK to 90% of SMBDATA,
= 400kHz
0.6
f
SMBCLK
10% to 10%, f
10% to 10%, f
90% to 90%
= 100kHz
= 400kHz
1.3
1.3
0.6
300
SMBCLK
SMBCLK
Clock Low Period
Clock High Period
Data Hold Time
t
µs
µs
ns
LOW
t
HIGH
f
= 100kHz
SMBCLK
SMBCLK
t
HD:DAT
f
= 400kHz (Note 6)
900
_______________________________________________________________________________________
3
5-Channel Precision Temperature Monitor
with Beta Compensation
ELECTRICAL CHARACTERISTICS (continued)
(V
= +3.0V to +3.6V, V
= V , T = -40°C to +125°C, unless otherwise noted. Typical values are at V
= +3.3V and T =
CC A
CC
STBY
CC
A
+25°C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
= 100kHz
MIN
250
100
TYP
MAX
UNITS
f
f
f
f
SMBCLK
SMBCLK
SMBCLK
SMBCLK
Data Setup Time
t
ns
µs
ns
SU:DAT
= 400kHz
= 100kHz
= 400kHz
1
Receive SMBCLK/SMBDATA Rise
Time
t
R
0.3
MAX694
Receive SMBCLK/SMBDATA Fall
Time
t
300
F
Pulse Width of Spike Suppressed
SMBus Timeout
t
0
50
45
ns
SP
t
SMBDATA low period for interface reset
25
37
ms
TIMEOUT
Note 2: All parameters are tested at T = +85°C. Specifications over temperature are guaranteed by design.
A
Note 3: Beta = 0.5 for channel 1 remote transistor.
Note 4: Timing specifications are guaranteed by design.
Note 5: The serial interface resets when SMBCLK is low for more than t
.
TIMEOUT
Note 6: A transition must internally provide at least a hold time to bridge the undefined region (300ns max) of SMBCLK’s falling edge.
4
_______________________________________________________________________________________
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
Typical Operating Characteristics
(V
= 3.3V, V
= V , T = +25°C, unless otherwise noted.)
STBY CC A
CC
SOFTWARE STANDBY SUPPLY CURRENT
vs. SUPPLY VOLTAGE
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
REMOTE-DIODE TEMPERATURE ERROR
vs. REMOTE-DIODE TEMPERATURE
3.8
3.7
3.6
3.5
3.4
3.3
3.2
3.1
3.0
650
600
550
500
450
400
350
5
4
LOW BETA DIODE CONNECTED TO
CHANNEL 1 WITH RESISTANCE
CANCELLATION AND LOW BETA
3
2
CHANNEL 2
CHANNEL 1
1
0
-1
-2
-3
-4
-5
3.0
3.1
3.2
3.3
3.4
3.5
3.6
3.0
3.2
3.4
3.6
0
25
50
75
100
125
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
LOCAL TEMPERATURE ERROR
vs. DIE TEMPERATURE
REMOTE-DIODE TEMPERATURE ERROR
vs. POWER-SUPPLY NOISE FREQUENCY
LOCAL TEMPERATURE ERROR
vs. POWER-SUPPLY NOISE FREQUENCY
4
3
5
4
5
4
100mV
100mV
P-P
P-P
3
3
2
2
2
CHANNEL 2
1
1
1
0
0
0
-1
-2
-3
-4
-5
-1
-2
-3
-4
-5
CHANNEL 1
-1
-2
-3
0
25
50
75
100
125
0.001
0.010
0.100
1.000
10.000
0.001
0.010
0.100
1.000
10.000
DIE TEMPERATURE (°C)
FREQUENCY (MHz)
FREQUENCY (MHz)
CH 1 REMOTE-DIODE TEMPERATURE
ERROR vs. CAPACITANCE
CH 2 REMOTE-DIODE TEMPERATURE ERROR
vs. COMMON-MODE NOISE FREQUENCY
CH 2 REMOTE-DIODE TEMPERATURE
ERROR vs. CAPACITANCE
5
4
4
5
4
100mV
P-P
3
2
3
3
2
2
1
1
1
0
0
0
-1
-2
-3
-4
-5
-1
-2
-3
-4
-5
-1
-2
-3
-4
-5
1
10
100
0.1
1.0
10.0
1
10
100
CAPACITANCE (nF)
FREQUENCY (MHz)
CAPACITANCE (nF)
_______________________________________________________________________________________
5
5-Channel Precision Temperature Monitor
with Beta Compensation
Pin Description
PIN
NAME
DXP1
DXN1
DXP2
DXN2
DXP3
DXN3
DXP4
DXN4
FUNCTION
TSSOP
TQFN-EP
Combined Current Source and A/D Positive Input for Channel 1 Remote Transistor.
Connect to the emitter of a low beta transistor. Leave unconnected or connect to V
no remote transistor is used. Place a 100pF capacitor between DXP1 and DXN1 for
noise filtering.
if
CC
1
15
MAX694
Base Input for Channel 1 Remote Diode. Connect to the base of a pnp temperature-
sensing transistor.
2
3
4
5
6
7
8
16
1
Combined Current Source and A/D Positive Input for Channel 2 Remote Diode. Connect
to the anode of a remote-diode-connected temperature-sensing transistor. Leave
if no remote diode is used. Place a 100pF capacitor
between DXP2 and DXN2 for noise filtering.
unconnected or connect to V
CC
Cathode Input for Channel 2 Remote Diode. Connect the cathode of the channel 2
remote-diode-connected transistor to DXN2.
2
Combined Current Source and A/D Positive Input for Channel 3 Remote Diode. Connect
to the anode of a remote-diode-connected temperature-sensing transistor. Leave
if no remote diode is used. Place a 100pF capacitor
between DXP3 and DXN3 for noise filtering.
3
unconnected or connect to V
CC
Cathode Input for Channel 3 Remote Diode. Connect the cathode of the channel 3
remote-diode-connected transistor to DXN3.
4
Combined Current Source and A/D Positive Input for Channel 4 Remote Diode. Connect
to the anode of a remote-diode-connected temperature-sensing transistor. Leave
if no remote diode is used. Place a 100pF capacitor
between DXP4 and DXN4 for noise filtering.
5
unconnected or connect to V
CC
Cathode Input for Channel 4 Remote Diode. Connect the cathode of the channel 4
remote-diode-connected transistor to DXN4.
6
Active-Low Standby Input. Drive STBY low to place the MAX6694 in standby mode, or
high for operate mode. Temperature and threshold data are retained in standby mode.
9
7
8
STBY
N.C.
10
11
12
13
No Connection. Must be connected to ground.
Overtemperature Active-Low, Open-Drain Output. OVERT asserts low when the
temperature of channels 1 and 4 exceeds the programmed threshold limit.
9
OVERT
10
11
V
Supply Voltage Input. Bypass to GND with a 0.1µF capacitor.
CC
SMBus Alert (Interrupt), Active-Low, Open-Drain Output. ALERT asserts low when the
temperature of any channel exceeds the programmed ALERT threshold.
ALERT
14
15
16
12
13
14
SMBDATA
SMBCLK
GND
SMBus Serial Data Input/Output. Connect to a pullup resistor.
SMBus Serial Clock Input. Connect to a pullup resistor.
Ground
Exposed Pad. Connect to a large ground plane to maximize thermal performance. Not
intended as an electrical connection point. (TQFN package only).
—
—
EP
6
_______________________________________________________________________________________
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
ADC Conversion Sequence
Detailed Description
In the default conversion mode, the MAX6694 starts the
The MAX6694 is a precision multichannel temperature
conversion sequence by measuring the temperature on
channel 1, followed by 2, 3, local channel, and 4. The
conversion result for each active channel is stored in
the corresponding temperature data register.
monitor that features one local and four remote temper-
ature-sensing channels with a programmable alert
threshold for each temperature channel and a program-
mable overtemperature threshold for channels 1 and 4
(see Figure 1). Communication with the MAX6694 is
achieved through the SMBus serial interface and a
dedicated alert output. The alarm outputs, OVERT and
ALERT, assert if the software-programmed temperature
thresholds are exceeded. ALERT typically serves as an
interrupt, while OVERT can be connected to a fan, sys-
tem shutdown, or other thermal-management circuitry.
Low-Power Standby Mode
Enter software standby mode by setting the STOP bit to
1 in the configuration 1 register. Enter hardware stand-
by by pulling STBY low. Software standby mode dis-
ables the ADC and reduces the supply current to
approximately 3µA. Hardware standby mode halts the
ADC clock, but the supply current is approximately
V
CC
MAX6694
DXP1
OVERT
ALARM
ALU
DXN1
DXP2
ALERT
CURRENT
SOURCES,
BETA
COMPEN-
SATION
AND MUX
DXN2
DXP3
INPUT
BUFFER
REGISTER BANK
ADC
COMMAND BYTE
REMOTE TEMPERATURES
LOCAL TEMPERATURES
ALERT THRESHOLD
DXN3
DXP4
REF
OVERT THRESHOLD
DXN4
ALERT RESPONSE ADDRESS
SMBus
INTERFACE
STBY
SMBCLK
SMBDATA
Figure 1. Internal Block Diagram
_______________________________________________________________________________________
7
5-Channel Precision Temperature Monitor
with Beta Compensation
350µA. During either software or hardware standby,
data is retained in memory. During hardware standby,
the SMBus interface is inactive. During software stand-
by, the SMBus interface is active and listening for
SMBus commands. The timeout is enabled if a start
condition is recognized on SMBus. Activity on the
SMBus causes the supply current to increase. If a
standby command is received while a conversion is in
progress, the conversion cycle is interrupted, and the
temperature registers are not updated. The previous
data is not changed and remains available.
SMBus Digital Interface
From a software perspective, the MAX6694 appears as
a series of 8-bit registers that contain temperature mea-
surement data, alarm threshold values, and control bits.
A standard SMBus-compatible, 2-wire serial interface is
used to read temperature data and write control bits
and alarm threshold data. The same SMBus slave
address also provides access to all functions.
The MAX6694 employs four standard SMBus protocols:
write byte, read byte, send byte, and receive byte
(Figure 2). The shorter receive byte protocol allows
quicker transfers, provided that the correct data regis-
ter was previously selected by a read byte instruction.
Use caution with the shorter protocols in multimaster
systems, since a second master could overwrite the
command byte without informing the first master. Figure
3 is the SMBus write-timing diagram and Figure 4 is the
SMBus read-timing diagram.
MAX694
Operating-Current Calculation
The MAX6694 operates at different operating-current
levels depending on how many external channels are in
use. Assume that I
is the operating current when
CC1
the MAX6694 is converting the remote channel 1 and
I
is the operating current when the MAX6694 is con-
CC2
verting the other channels. For the MAX6694 with
remote channel 1 and n other remote channels con-
nected, the operating current is:
The remote diode 1 measurement channel provides 11
bits of data (1 LSB = +0.125°C). All other temperature-
measurement channels provide 8 bits of temperature
data (1 LSB = +1°C). The 8 most significant bits (MSBs)
I
= (2 x I
+ I
+ n x I
)/(n + 3)
CC
CC1
CC2
CC2
WRITE BYTE FORMAT
S
ADDRESS
WR
ACK
COMMAND
ACK
DATA
ACK
P
7 BITS
8 BITS
8 BITS
1
SLAVE ADDRESS: EQUIVA-
LENT TO CHIP-SELECT LINE OF
A 3-WIRE INTERFACE
DATA BYTE: DATA GOES INTO THE REGISTER
SET BY THE COMMAND BYTE (TO SET
THRESHOLDS, CONFIGURATION MASKS, AND
SAMPLING RATE)
COMMAND BYTE: SELECTS
TO WHICH REGISTER YOU
ARE WRITING
READ BYTE FORMAT
S
ADDRESS
WR
ACK
COMMAND
ACK
S
ADDRESS
7 BITS
RD
ACK
ACK
DATA
///
P
7 BITS
8 BITS
8 BITS
SLAVE ADDRESS: EQUIVA-
LENT TO CHIP SELECT LINE
COMMAND BYTE: SELECTS
FROM WHICH REGISTER YOU
ARE READING
SLAVE ADDRESS: REPEATED
DUE TO CHANGE IN DATA-
FLOW DIRECTION
DATA BYTE: READS FROM
THE REGISTER SET BY THE
COMMAND BYTE
SEND BYTE FORMAT
S
RECEIVE BYTE FORMAT
ADDRESS
WR
ACK
COMMAND
ACK
P
S
ADDRESS
RD
DATA
///
P
7 BITS
8 BITS
7 BITS
8 BITS
COMMAND BYTE: SENDS COM-
MAND WITH NO DATA, USUALLY
USED FOR ONE-SHOT COMMAND
DATA BYTE: READS DATA FROM
THE REGISTER COMMANDED
BY THE LAST READ BYTE OR
WRITE BYTE TRANSMISSION;
ALSO USED FOR SMBus ALERT
RESPONSE RETURN ADDRESS
S = START CONDITION. SHADED = SLAVE TRANSMISSION.
P = STOP CONDITION. /// = NOT ACKNOWLEDGED.
Figure 2. SMBus Protocols
8
_______________________________________________________________________________________
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
A
B
C
D
E
F
G
H
I
J
K
L
M
t
t
HIGH
LOW
SMBCLK
SMBDATA
t
t
t
t
HD:DAT
HD:STA
SU:STA
SU:DAT
t
t
SU:STO
BUF
A = START CONDITION.
F = ACKNOWLEDGE BIT CLOCKED INTO MASTER.
G = MSB OF DATA CLOCKED INTO MASTER.
H = LSB OF DATA CLOCKED INTO MASTER.
I = MASTER PULLS DATA LINE LOW.
J = ACKNOWLEDGE CLOCKED INTO SLAVE.
K = ACKNOWLEDGE CLOCK PULSE.
L = STOP CONDITION.
B = MSB OF ADDRESS CLOCKED INTO SLAVE.
C = LSB OF ADDRESS CLOCKED INTO SLAVE.
D = R/W BIT CLOCKED INTO SLAVE.
M = NEW START CONDITION.
E = SLAVE PULLS SMBDATA LINE LOW.
Figure 3. SMBus Write-Timing Diagram
A
B
C
D
E
F
G
H
I
J
K
L
M
t
t
HIGH
LOW
SMBCLK
SMBDATA
t
t
t
t
BUF
t
SU:STA HD:STA
SU:STO
SU:DAT
A = START CONDITION.
E = SLAVE PULLS SMBDATA LINE LOW.
I = MASTER PULLS DATA LINE LOW.
J = ACKNOWLEDGE CLOCKED INTO SLAVE.
K = ACKNOWLEDGE CLOCK PULSE.
L = STOP CONDITION.
B = MSB OF ADDRESS CLOCKED INTO SLAVE.
C = LSB OF ADDRESS CLOCKED INTO SLAVE.
D = R/W BIT CLOCKED INTO SLAVE.
F = ACKNOWLEDGE BIT CLOCKED INTO MASTER.
G = MSB OF DATA CLOCKE D INTO SLAVE.
H = LSB OF DATA CLOCKED INTO SLAVE.
M = NEW START CONDITION.
Figure 4. SMBus Read-Timing Diagram
Table 1. Main Temperature Register
(High Byte) Data Format
Table 2. Extended Resolution Temperature
Register (Low Byte) Data Format
TEMP (°C)
DIGITAL OUTPUT
0111 1111
0111 1111
0111 1110
0001 1001
0000 0000
0000 0000
1111 1111
TEMP (°C)
0
DIGITAL OUTPUT
000X XXXX
001X XXXX
010X XXXX
011X XXXX
100X XXXX
101X XXXX
110X XXXX
111X XXXX
> +127
+127
+0.125
+0.250
+0.375
+0.500
+0.625
+0.750
+0.875
+126
+25
0
< 0
Diode fault (short or open)
_______________________________________________________________________________________
9
5-Channel Precision Temperature Monitor
with Beta Compensation
can be read from the local temperature and remote
temperature registers. The remaining 3 bits for remote
diode 1 can be read from the extended temperature
register. If extended resolution is desired, the extended
resolution register should be read first. This prevents
the most significant bits from being overwritten by new
conversion results until they have been read. If the
most significant bits have not been read within an
SMBus timeout period (nominally 37ms), normal updat-
ing continues. Table 1 shows the main temperature
register (high-byte) data format, and Table 2 shows the
extended resolution register (low-byte) data format.
The ALERT output is open-drain so that multiple devices
can share a common interrupt line. All ALERT interrupts
can be masked using the configuration 2 register. The
POR state of these registers is shown in Table 3.
ALERT Response Address
The SMBus alert response interrupt pointer provides
quick fault identification for simple slave devices that
lack the complex logic needed to be a bus master.
Upon receiving an interrupt signal, the host master can
broadcast a receive byte transmission to the alert
response slave address (see the Slave Address sec-
tion). Then, any slave device that generated an inter-
rupt attempts to identify itself by putting its own
address on the bus.
MAX694
Diode Fault Detection
If a channel’s input DXP_ and DXN_ are left open, the
MAX6694 detects a diode fault. An open diode fault
does not cause either ALERT or OVERT to assert. A bit
in the status register for the corresponding channel is
set to 1 and the temperature data for the channel is
stored as all 1s (FFh). It takes approximately 4ms for
the MAX6694 to detect a diode fault. Once a diode fault
is detected, the MAX6694 goes to the next channel in
the conversion sequence.
The alert response can activate several different slave
devices simultaneously, similar to the I2C General Call.
If more than one slave attempts to respond, bus arbitra-
tion rules apply, and the device with the lower address
code wins. The losing device does not generate an
acknowledgment and continues to hold the ALERT line
low until cleared. (The conditions for clearing an alert
vary depending on the type of slave device.)
Successful completion of the alert response protocol
clears the output latch. If the condition that caused the
alert still exists, the MAX6694 reasserts the ALERT
interrupt at the end of the next conversion.
Alarm Threshold Registers
There are seven alarm threshold registers that store
overtemperature ALERT and OVERT threshold values.
Five of these registers are dedicated to storing one
local alert temperature threshold limit and four remote
alert temperature threshold limits (see the ALERT
Interrupt Mode section). The remaining two registers
are dedicated to remote channels 1 and 4 to store
overtemperature threshold limits (see the OVERT
Overtemperature Alarm section). Access to these regis-
ters is provided through the SMBus interface.
OVERT Overtemperature Alarms
The MAX6694 has two overtemperature registers that
store remote alarm threshold data for the OVERT output.
OVERT is asserted when a channel’s measured temper-
ature is greater than the value stored in the correspond-
ing threshold register. OVERT remains asserted until the
temperature drops below the programmed threshold
minus 4°C hysteresis. An overtemperature output can
be used to activate a cooling fan, send a warning, initi-
ate clock throttling, or trigger a system shutdown to pre-
vent component damage. See Table 3 for the POR state
of the overtemperature threshold registers.
ALERT Interrupt Mode
An ALERT interrupt occurs when the internal or external
temperature reading exceeds a high-temperature limit
(user programmable). The ALERT interrupt output signal
can be cleared by reading the status register(s) associ-
ated with the fault(s) or by successfully responding to an
alert response address transmission by the master. In
both cases, the alert is cleared but is reasserted at the
end of the next conversion if the fault condition still
exists. The interrupt does not halt automatic conversions.
Command Byte Functions
The 8-bit command byte register (Table 3) is the master
index that points to the various other registers within the
MAX6694. This register’s POR state is 0000 0000.
10 ______________________________________________________________________________________
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
Table 3. Command Byte Register Bit Assignment
ADDRESS POR STATE READ/
REGISTER
DESCRIPTION
(HEX)
(HEX)
WRITE
Local
07
01
02
03
04
41
42
43
44
45
46
17
00
00
00
00
00
0C
00
00
00
00
00
5A
R
R
Read local temperature register
Remote 1
Read channel 1 remote temperature register
Read channel 2 remote temperature register
Read channel 3 remote temperature register
Read channel 4 remote temperature register
Read/write configuration register 1
Read/write configuration register 2
Read/write configuration register 3
Read status register 1
Remote 2
R
Remote 3
R
Remote 4
R
Configuration 1
Configuration 2
Configuration 3
Status1
R/W
R/W
R/W
R
Status2
R
Read status register 2
Status3
R
Read status register 3
Local ALERT High Limit
R/W
Read/write local alert high-temperature threshold limit register
Read/write channel 1 remote-diode alert high-temperature
threshold limit register
Remote 1 ALERT High Limit
Remote 2 ALERT High Limit
Remote 3 ALERT High Limit
Remote 4 ALERT High Limit
Remote 1 OVERT High Limit
Remote 4 OVERT High Limit
11
12
13
14
21
24
6E
7F
64
64
6E
7F
R/W
R/W
R/W
R/W
R/W
R/W
Read/write channel 2 remote-diode alert high-temperature
threshold limit register
Read/write channel 3 remote-diode alert high-temperature
threshold limit register
Read/write channel 4 remote-diode alert high-temperature
threshold limit register
Read/write channel 1 remote-diode overtemperature threshold
limit register
Read/write channel 4 remote-diode overtemperature threshold
limit register
Remote 1 Extended
Temperature
09
0A
00
R
R
Read channel 1 remote-diode extended temperature register
Read manufacturer ID
Manufacturer ID
4D
______________________________________________________________________________________ 11
5-Channel Precision Temperature Monitor
with Beta Compensation
In both cases, the alert is cleared even if the fault condi-
Configuration Byte Functions
There are three read-write configuration registers
(Tables 4, 5, and 6) that can be used to control the
MAX6694’s operation.
tion exists, but the ALERT output reasserts at the end of
the next conversion. The bits indicating the fault for the
OVERT interrupt output clear only on reading the status 2
register even if the fault conditions still exist. Reading the
status 2 register does not clear the OVERT interrupt out-
put. To eliminate the fault condition, either the measured
temperature must drop below the temperature threshold
minus the hysteresis value (4°C), or the trip temperature
must be set at least 4°C above the current temperature.
Configuration 1 Register
The configuration 1 register (Table 4) has several func-
tions. Bit 7 (MSB) is used to put the MAX6694 either in
software standby mode (STOP) or continuous conver-
sion mode. Bit 6 resets all registers to their POR condi-
tions and then clears itself. Bit 5 disables the SMBus
timeout. Bit 3 enables resistance cancellation on chan-
nel 1. See the Series Resistance Cancellation section
for more details. Bit 2 enables beta compensation on
channel 1. See the Beta Compensation section for
more details. The remaining bits of the configuration 1
register are not used. The POR state of this register is
0000 1100 (0Ch).
MAX694
Applications Information
Remote-Diode Selection
The MAX6694 directly measures the die temperature of
CPUs and other ICs that have on-chip temperature-
sensing diodes (see the Typical Application Circuit) or
it can measure the temperature of a discrete diode-
connected transistor.
Configuration 2 Register
The configuration 2 register functions are described in
Table 5. Bits 6, 3, 2, 1, and 0 are used to mask the
ALERT interrupt output. Bit 6 masks the local alert inter-
rupt and bits 3 through bit 0 mask the remote alert
interrupts. The power-up state of this register is 0000
0000 (00h).
Effect of Ideality Factor
The accuracy of the remote temperature measure-
ments depends on the ideality factor (n) of the remote
“diode” (actually a transistor). The MAX6694 is opti-
mized for n = 1.006 (channel 1) and n = 1.008 (chan-
nels 2, 3, and 4). A thermal diode on the substrate of an
IC is normally a pnp with the base and emitter brought
out to the collector (diode connection) grounded. DXP_
must be connected to the anode (emitter) and DXN_
must be connected to the cathode (base) of this pnp. If
a sense transistor with an ideality factor other than
1.006 or 1.008 is used, the output data is different from
the data obtained with the optimum ideality factor.
Fortunately, the difference is predictable. Assume a
remote-diode sensor designed for a nominal ideality
Configuration 3 Register
Table 6 describes the configuration 3 register. Bits 3
and 0 mask the OVERT interrupt output for channels 4
and 1. The remaining bits, 7, 6, 5, 4, 2, and 1, are
reserved. The power-up state of this register is 0000
0000 (00h).
Status Register Functions
Status registers 1, 2, and 3 (Tables 7, 8, and 9) indicate
which (if any) temperature thresholds have been
exceeded and if there is an open-circuit or short-circuit
fault detected with the external sense junctions. Status
register 1 indicates if the measured temperature has
exceeded the threshold limit set in the ALERT registers
for the local or remote-sensing diodes. Status register 2
indicates if the measured temperature has exceeded
the threshold limit set in the OVERT registers. Status
register 3 indicates if there is a diode fault (open or
short) in any of the remote-sensing channels.
factor n
is used to measure the temperature of
NOMINAL
a diode with a different ideality factor n . The measured
1
temperature T can be corrected using:
M
⎛
⎞
n
1
T
= T
ACTUAL
M
⎜
⎟
n
⎝
⎠
NOMINAL
where temperature is measured in Kelvin and
for channel 1 of the MAX6694 is 1.009. As
n
NOMIMAL
an example, assume you want to use the MAX6694 with
a CPU that has an ideality factor of 1.002. If the diode
has no series resistance, the measured data is related
to the real temperature as follows:
Bits in the alert status register clear by a successful
read, but set again after the next conversion unless the
fault is corrected, either by a drop in the measured tem-
perature or an increase in the threshold temperature.
⎛
⎞
n
1.009
1.002
⎛
⎞
NOMINAL
T
= T
×
= T
×
= T (1.00699)
M
⎜
⎝
⎟
⎠
ACTUAL
M
M
⎜
⎟
The ALERT interrupt output follows the status flag bit.
Once the ALERT output is asserted, it can be
deasserted by either reading status register 1 or by
successfully responding to an alert response address.
n
1
⎝
⎠
12 ______________________________________________________________________________________
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
Table 4. Configuration 1 Register
POR
STATE
BIT
7 (MSB)
6
NAME
STOP
POR
FUNCTION
Standby Mode Control Bit. If STOP is set to logic 1, the MAX6694 stops
converting and enters standby mode.
0
0
Reset Bit. Set to logic 1 to put the device into its power-on state. This bit is self-
clearing.
5
4
TIMEOUT
0
0
Timeout Enable Bit. Set to logic 0 to enable SMBus timeout.
Reserved. Must set to 0.
Reserved
Resistance
cancellation
Resistance Cancellation Bit. When set to logic 1, the MAX6694 cancels series
resistance in the channel 1 thermal diode.
3
2
1
1
Beta Compensation Bit. When set to logic 1, the MAX6694 compensates for low
beta in the channel 1 thermal sensing transistor.
Beta compensation
1
0
Reserved
Reserved
0
0
—
—
Table 5. Configuration 2 Register
POR
STATE
BIT
NAME
FUNCTION
7 (MSB)
Reserved
Mask Local ALERT
Reserved
0
0
0
0
0
0
0
0
—
6
5
4
3
2
1
0
Local Alert Mask. Set to logic 1 to mask local channel ALERT.
—
Reserved
—
Mask ALERT 4
Mask ALERT 3
Mask ALERT 2
Mask ALERT 1
Channel 4 Alert Mask. Set to logic 1 to mask channel 4 ALERT.
Channel 3 Alert Mask. Set to logic 1 to mask channel 3 ALERT.
Channel 2 Alert Mask. Set to logic 1 to mask channel 2 ALERT.
Channel 1 Alert Mask. Set to logic 1 to mask channel 1 ALERT.
Table 6. Configuration 3 Register
POR
STATE
BIT
NAME
FUNCTION
7 (MSB)
Reserved
Reserved
Reserved
Reserved
0
0
0
0
—
—
—
—
6
5
4
Channel 4 Remote-Diode OVERT Mask Bit. Set to logic 1 to mask channel 4
OVERT.
3
Mask OVERT 4
0
2
1
Reserved
Reserved
0
0
—
—
Channel 1 Remote-Diode OVERT Mask Bit. Set to logic 1 to mask channel 1
OVERT.
0
Mask OVERT 1
0
______________________________________________________________________________________ 13
5-Channel Precision Temperature Monitor
with Beta Compensation
Table 7. Status 1 Register
POR
STATE
BIT
NAME
FUNCTION
7 (MSB)
Reserved
0
—
Local Channel High-Alert Bit. This bit is set to logic 1 when the local
temperature exceeds the temperature threshold limit in the local ALERT high-
limit register.
6
Local ALERT
0
MAX694
5
4
Reserved
Reserved
0
0
—
—
Channel 4 Remote-Diode High-Alert Bit. This bit is set to logic 1 when the
channel 4 remote-diode temperature exceeds the temperature threshold limit
in the remote 4 ALERT high-limit register.
3
2
1
0
Remote 4 ALERT
Remote 3 ALERT
Remote 2 ALERT
Remote 1 ALERT
0
0
0
0
Channel 3 Remote-Diode High-Alert Bit. This bit is set to logic 1 when the
channel 3 remote-diode temperature exceeds the programmed temperature
threshold limit in the remote 3 ALERT high-limit register.
Channel 2 Remote-Diode High-Alert Bit. This bit is set to logic 1 when the
channel 2 remote-diode temperature exceeds the temperature threshold limit
in the remote 2 ALERT high-limit register.
Channel 1 Remote-Diode High-Alert Bit. This bit is set to logic 1 when the
channel 1 remote-diode temperature exceeds the temperature threshold limit
in the remote 1 ALERT high-limit register.
Table 8. Status 2 Register
POR
STATE
BIT
NAME
FUNCTION
7 (MSB)
Reserved
Reserved
Reserved
Reserved
0
0
0
0
—
—
—
—
6
5
4
Channel 4 Remote-Diode Overtemperature Status Bit. This bit is set to logic 1
when the channel 4 remote-diode temperature exceeds the temperature
threshold limit in the remote 4 OVERT high-limit register.
3
Remote 4 OVERT
0
2
1
Reserved
Reserved
0
0
—
—
Channel 1 Remote-Diode Overtemperature Status Bit. This bit is set to logic 1
when the channel 1 remote-diode temperature exceeds the temperature
threshold limit in the remote 1 OVERT high-limit register.
0
Remote 1 OVERT
0
14 ______________________________________________________________________________________
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
Table 9. Status 3 Register
POR
STATE
BIT
NAME
FUNCTION
7 (MSB)
Reserved
Reserved
Reserved
0
0
0
—
6
5
Not Used. 0 at POR, then 1.
Not Used. 0 at POR, then 1.
Channel 4 Remote-Diode Fault Bit. This bit is set to 1 when DXP4 and DXN4
are open circuit or when DXP4 is connected to V
4
3
2
Diode fault 4
Diode fault 3
Diode fault 2
0
0
0
.
CC
Channel 3 Remote-Diode Fault Bit. This bit is set to 1 when DXP3 and DXN3
are open circuit or when DXP3 is connected to V
.
CC
Channel 2 Remote-Diode Fault Bit. This bit is set to 1 when DXP2 and DXN2
are open circuit or when DXP2 is connected to V
.
CC
Channel 1 Remote-Diode Fault Bit. This bit is set to 1 when DXP1 and DXN1
1
0
Diode fault 1
Reserved
0
0
are open circuit or when DXP1 is connected to V
.
CC
—
For a real temperature of +85°C (358.15K), the mea-
sured temperature is +84.41°C (357.56K), an error of
-0.590°C.
function that, when enabled, eliminates the effect of low
beta values. This function is enabled at power-up and
can be disabled using bit 2 of the configuration 1 regis-
ter. Whenever low beta compensation is enabled,
series-resistance cancellation must be enabled. When
a sense transistor’s base and collector are shorted
together (as with a discrete sensing “diode”), disable
beta compensation.
Series Resistance Cancellation
Some thermal diodes on high-power ICs can have
excessive series resistance, which can cause tempera-
ture measurement errors with conventional remote tem-
perature sensors. Channel 1 of the MAX6694 has a
series resistance cancellation feature (enabled by bit 3
of the configuration 1 register) that eliminates the effect
of diode series resistance. Set bit 3 to 1 if the series
resistance is large enough to affect the accuracy of
channel 1. The series resistance cancellation function
increases the conversion time for channel 1 by 125ms.
This feature cancels the bulk resistance of the sensor
and any other resistance in series (wire, contact resis-
tance, etc.). The cancellation range is from 0Ω to 100Ω.
Discrete Remote Diodes
When the remote-sensing diode is a discrete transistor,
its collector and base must be connected together.
Table 10 lists examples of discrete transistors that are
appropriate for use with the MAX6694. The transistor
must be a small-signal type with a relatively high for-
ward voltage; otherwise, the A/D input voltage range
Table 10. Remote-Sensors Transistor
Manufacturers (for Channels 2, 3, and 4)
Beta Compensation
The MAX6694 is optimized for use with a substrate pnp
remote-sensing transistor on the die of the target IC.
DXP1 connects to the emitter of the sensing transistor
and DXN1 connects to the base. The collector is
grounded. Such transistors can have very low beta
(less than 1) when built in processes with 65nm and
smaller geometries. Because of the very low beta, stan-
dard “remote diode” temperature sensors may exhibit
large errors when used with these transistors. Channel
1 of the MAX6694 incorporates a beta compensation
MANUFACTURER
Central Semiconductor (USA)
Rohm Semiconductor (USA)
Samsung (Korea)
MODEL NO.
CMPT3904
SST3904
KST3904-TF
SMBT3904
Siemens (Germany)
Zetex (England)
FMMT3904CT-ND
Note: Discrete transistors must be diode connected (base
shorted to collector).
______________________________________________________________________________________ 15
5-Channel Precision Temperature Monitor
with Beta Compensation
can be violated. The forward voltage at the highest
expected temperature must be greater than 0.25V at
10µA, and at the lowest expected temperature, the for-
ward voltage must be less than 0.95V at 100µA. Large
power transistors must not be used. Also, ensure that
the base resistance is less than 100Ω. Tight specifica-
tions for forward current gain (50 < ß < 150, for exam-
ple) indicate that the manufacturer has good process
When measuring temperature with discrete remote
transistors, the best thermal response times are
obtained with transistors in small packages (i.e., SOT23
or SC70). Take care to account for thermal gradients
between the heat source and the sensor, and ensure
that stray air currents across the sensor package do
not interfere with measurement accuracy. Self-heating
does not significantly affect measurement accuracy.
Remote-sensor self-heating due to the diode current
source is negligible.
controls and that the devices have consistent V char-
BE
MAX694
acteristics. Manufacturers of discrete transistors do not
normally specify or guarantee ideality factor. This is
normally not a problem since good-quality discrete
transistors tend to have ideality factors that fall within a
relatively narrow range. We have observed variations in
remote temperature readings of less than 2°C with a
variety of discrete transistors. Still, it is good design
practice to verify good consistency of temperature
readings with several discrete transistors from any
manufacturer under consideration.
ADC Noise Filtering
The integrating ADC has good noise rejection for low-
frequency signals, such as power-supply hum. In envi-
ronments with significant high-frequency EMI, connect
an external 100pF capacitor between DXP_ and DXN_.
Larger capacitor values can be used for added filter-
ing, but do not exceed 100pF because it can introduce
errors due to the rise time of the switched current
source. High-frequency noise reduction is needed for
high-accuracy remote measurements. Noise can be
reduced with careful PCB layout as discussed in the
PCB Layout section.
Unused Diode Channels
If one or more of the remote diode channels is not
needed, disconnect the DXP and DXN inputs for that
channel, or connect the DXP input to V . The status
CC
Slave Address
The slave address for the MAX6694 is shown in Table 11.
register indicates a diode "fault" for this channel and the
channel is ignored during the temperature-measure-
ment sequence. It is also good practice to mask any
unused channels immediately upon power-up by set-
ting the appropriate bits in the Configuration 2 and
Configuration 3 registers. This will prevent unused
channels from causing ALERT or OVERT to assert.
Table 11. Slave Address
DEVICE ADDRESS
A7
A6
A5
A4
A3
A2
A1
A0
1
0
0
1
1
0
1
R/W
Thermal Mass and Self-Heating
When sensing local temperature, the MAX6694 mea-
sures the temperature of the PCB to which it is sol-
dered. The leads provide a good thermal path between
the PCB traces and the die. As with all IC temperature
sensors, thermal conductivity between the die and the
ambient air is poor by comparison, making air tempera-
ture measurements impractical. Because the thermal
mass of the PCB is far greater than that of the
MAX6694, the device follows temperature changes on
the PCB with little or no perceivable delay. When mea-
suring the temperature of a CPU or other IC with an on-
chip sense junction, thermal mass has virtually no
effect; the measured temperature of the junction tracks
the actual temperature within a conversion cycle.
PCB Layout
Follow these guidelines to reduce the measurement
error when measuring remote temperature:
1) Place the MAX6694 as close as is practical to the
remote diode. In noisy environments, such as a com-
puter motherboard, this distance can be 4in to 8in
(typ). This length can be increased if the worst noise
sources are avoided. Noise sources include CRTs,
clock generators, memory buses, and PCI buses.
2) Do not route the DXP-DXN lines next to the deflec-
tion coils of a CRT. Also, do not route the traces
across fast digital signals, which can easily intro-
duce +30°C error, even with good filtering.
16 ______________________________________________________________________________________
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
3) Route the DXP and DXN traces in parallel and in
close proximity to each other. Each parallel pair of
traces should go to a remote diode. Route these
traces away from any higher voltage traces, such as
+12VDC. Leakage currents from PCB contamination
must be dealt with carefully since a 20MΩ leakage
path from DXP to ground causes about +1°C error.
If high-voltage traces are unavoidable, connect
guard traces to GND on either side of the DXP-DXN
traces (Figure 5).
GND
DXP
DXN
GND
5 mils TO 10 mils
MINIMUM
5 mils TO 10 mils
5 mils TO 10 mils
5 mils TO 10 mils
4) Route through as few vias and crossunders as possi-
ble to minimize copper/solder thermocouple effects.
Figure 5. Recommended DXP-DXN PCB Traces. The two outer
guard traces are recommended if high-voltage traces are near
the DXN and DXP traces.
5) Use wide traces when practical. 5mil to 10mil traces
are typical. Be aware of the effect of trace resistance on
temperature readings when using long, narrow traces.
6) When the power supply is noisy, add a resistor (up
tances up to 100ft in a noisy environment. At the
device, connect the twisted pair to DXP and DXN and
the shield to GND. Leave the shield unconnected at the
remote sensor. For very long cable runs, the cable’s
parasitic capacitance often provides noise filtering, so
the 100pF capacitor can often be removed or reduced
in value. Cable resistance also affects remote-sensor
accuracy. For every 1Ω of series resistance, the error is
approximately +0.5°C.
to 47Ω) in series with V
.
CC
Twisted-Pair and Shielded Cables
Use a twisted-pair cable to connect the remote sensor
for remote-sensor distances longer than 8in or in very
noisy environments. Twisted-pair cable lengths can be
between 6ft and 12ft before noise introduces excessive
errors. For longer distances, the best solution is a
shielded twisted pair like that used for audio micro-
phones. For example, Belden #8451 works well for dis-
______________________________________________________________________________________ 17
5-Channel Precision Temperature Monitor
with Beta Compensation
MAX694
Pin Configurations
TOP VIEW
TOP VIEW
+
DXP1
DXN1
DXP2
DXN2
DXP3
DXN3
DXP4
DXN4
1
2
3
4
5
6
7
8
16 GND
15 SMBCLK
14 SMBDATA
13 ALERT
MAX694
MAX6694
N.C.
13
14
15
16
8
7
6
5
SMBCLK
STBY
DXN4
DXP4
GND
DXP1
DXN1
MAX6694
12
V
CC
11 OVERT
10
9
N.C.
+
STBY
TSSOP
TQFN-EP*
*EXPOSED PAD. CONNECT EP TO GND.
Chip Information
Package Information
For the latest package outline information, go to
PROCESS: BiCMOS
www.maxim-ic.com/packages.
PACKAGE TYPE PACKAGE CODE DOCUMENT NO.
16 TSSOP
U16-1
21-0066
21-0140
16 TQFN-EP
T1655-2
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.
18 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2008 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
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MAXIM
MAX6695YAUB+T
Serial Switch/Digital Sensor, 11 Bit(s), 1.50Cel, BICMOS, Square, 10 Pin, Surface Mount, 3 X 3 MM, LEAD FREE, MO-187C-BA, USOP-10
MAXIM
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