Rainbow Electronics MAX6642 - Manual

General Description
The MAX6642 is a precise, two-channel digital temper-
ature sensor. It accurately measures the temperature of
its own die and a remote PN junction, and reports the
temperature data over a 2-wire serial interface. The
remote PN junction is typically a substrate PNP transis-
tor on the die of a CPU, ASIC, GPU, or FPGA. The
remote PN junction can also be a discrete diode-con-
nected small-signal transistor.
The 2-wire serial interface accepts standard system
management bus (SMBus™), Write Byte, Read Byte,
Send Byte, and Receive Byte commands to read the
temperature data and to program the alarm thresholds.
To enhance system reliability, the MAX6642 includes an
SMBus timeout. The temperature data format is 10 bit
with the least significant bit (LSB) corresponding to
+0.25°C. The ALERT output asserts when the local or
remote overtemperature thresholds are violated. A fault
queue may be used to prevent the ALERT output from
setting until two consecutive faults have been detected.
Measurements can be done autonomously or in a sin-
gle-shot mode.
Remote accuracy is ±1°C maximum error between
+60°C and +100°C. The MAX6642 operates from -40°C
to +125°C, and measures remote temperatures
between 0°C and +150°C. The MAX6642 is available in
a 6-pin TDFN package.
Applications
Desktop Computers
Notebook Computers
Servers
Thin Clients
Test and Measurement
Workstations
Graphic Cards
Features
♦ Dual Channel: Measures Remote and Local
Temperature
♦ +0.25°C Resolution
♦ High Accuracy ±1°C (max) (Remote) and
±2°C (Local) from +60°C to +100°C
♦ Measures Remote Temperature Up to +150°C
♦ Programmable Overtemperature Alarm
Temperature Thresholds
♦ SMBus/I 2 C TM -Compatible Interface
♦ Tiny TDFN Package
MAX6642
±1°C, SMBus-Compatible Remote/Local
Temperature Sensor with Overtemperature Alarm
________________________________________________________________ Maxim Integrated Products 1
Ordering Information
19-2920; Rev 0; 8/03
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.
PART TEMP RANGE PIN-PACKAGE
MAX6642ATT90-T -40°C to +125°C 6 TDFN
MAX6642ATT92-T -40°C to +125°C 6 TDFN
MAX6642ATT94-T -40°C to +125°C 6 TDFN
MAX6642ATT96-T -40°C to +125°C 6 TDFN
MAX6642ATT98-T -40°C to +125°C 6 TDFN
MAX6642ATT9A-T -40°C to +125°C 6 TDFN
MAX6642ATT9C-T -40°C to +125°C 6 TDFN
MAX6642ATT9E-T -40°C to +125°C 6 TDFN
MAX6642
2200pF
0.1 µF
µP
DXP
GND
SDA
SCLK
ALERT
DATA
CLOCK
INTERRUPT TO µP
47 Ω
10k Ω EACH
3.3V
V CC
Typical Operating Circuit
PART MEASURED TEMP RANGE
TOP
MARK
MAX6642ATT90-T 0°C to +150°C AFC
MAX6642ATT92-T 0°C to +150°C AFD
MAX6642ATT94-T 0°C to +150°C AFE
MAX6642ATT96-T 0°C to +150°C AFF
MAX6642ATT98-T 0°C to +150°C AEW
MAX6642ATT9A-T 0°C to +150°C AFG
MAX6642ATT9C-T 0°C to +150°C AFH
MAX6642ATT9E-T 0°C to +150°C AFI
Selector Guide
SMBus is a trademark of Intel Corp.
Purchase of I
2 C components of Maxim Integrated Products, Inc.
or one of its sublicensed Associated Companies, conveys a
license under the Philips I
2 C Patent Rights to use these compo-
nents in an I 2 C system, provided that the system conforms to the
I 2 C Standard Specification as defined by Philips.
Pin Configuration and Functional Diagram appear at end of
data sheet.