Rainbow Electronics MAX6692 - Manual

General Description
The MAX6648/MAX6692 are precise, two-channel digi-
tal temperature sensors. They accurately measure the
temperature of their own die and a remote PN junction,
and report the temperature in digital form using a 2-wire
serial interface. The remote PN junction is typically the
emitter-base junction of a common-collector PNP on a
CPU, FPGA, or ASIC.
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 MAX6648/MAX6692
include an SMBus timeout. A fault queue prevents the
ALERT and OVERT outputs from setting until a fault has
been detected one, two, or three consecutive times
(programmable).
The MAX6648/MAX6692 provide two system alarms:
ALERT and OVERT. ALERT asserts when any of four tem-
perature conditions are violated: local overtemperature,
remote overtemperature, local undertemperature, or
remote undertemperature. OVERT asserts when the tem-
perature rises above the value in either of the two OVERT
limit registers. The OVERT output can be used to activate
a cooling fan, or to trigger a system shutdown.
Measurements can be done autonomously, with the
conversion rate programmed by the user, or in a single-
shot mode. The adjustable conversion rate allows the
user to optimize supply current and temperature
update rate to match system needs.
Remote accuracy is ±0.8°C maximum error between
+25°C and +125°C with no calibration needed. The
MAX6648/MAX6692 operate from -55°C to +125°C, and
measure temperatures between 0°C and +125°C. The
MAX6648 is available in an 8-pin µMAX package, and the
MAX6692 is available in 8-pin µMAX and SO packages.
Applications
Desktop Computers
Notebook Computers
Servers
Thin Clients
Workstations
Test and Measurement
Multichip Modules
Features
♦ Dual Channel: Measures Remote and Local
Temperature
♦ 0.125°C Resolution
♦ High Accuracy: ±0.8°C (max) from +25°C to
+125°C (Remote), and ±2°C (max) from +60°C to
+100°C (Local)
♦ Two Alarm Outputs: ALERT and OVERT
♦ Two Default OVERT Thresholds Available
MAX6648: +110°C
MAX6692: +85°C
♦ Programmable Conversion Rate
♦ SMBus-Compatible Interface
♦ SMBus Timeout
♦ Programmable Under/Overtemperature Alarm
Thresholds
MAX6648/MAX6692
Precision SMBus-Compatible Remote/Local
Temperature Sensors with Overtemperature Alarms
________________________________________________________________ Maxim Integrated Products 1
Ordering Information
V CC
DXP
DXN
10k Ω EACH
CLOCK
TO FAN DRIVER OR
SYSTEM SHUTDOWN
3.3V
DATA
INTERRUPTED TO µP
200 Ω 0.1 µF
SDA
SCLK
ALERT
GND
2200pF
µP
MAX6648
MAX6692
OVERT
Typical Operating Circuit
19-2545; Rev 0; 8/02
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 MEASURED
TEMP RANGE
MAX6648MUA* -55°C to +125°C 8 µMAX 0°C to +125°C
MAX6692MUA -55°C to +125°C 8 µMAX 0°C to +125°C
MAX6692MSA -55°C to +125°C 8 SO 0°C to +125°C
SMBus is a trademark of Intel Corp.
Pin Configuration and Functional Diagram appear at end of
data sheet.
*Future product—contact factory for availability.