19-1483; Rev 0; 4/99
Re m o t e /Lo c a l Te m p e ra t u re S e n s o r w it h Du a l-
Ala rm Ou t p u t s a n d S MBu s S e ria l In t e rfa c e
MAX619
________________Ge n e ra l De s c rip t io n
____________________________Fe a t u re s
The MAX1619 is a precise digital thermometer that reports
the temperature of both a remote sensor and its own
package. The remote sensor is a diode-connected transis-
tor—typically a low-cost, easily mounted 2N3904 NPN
type—that replaces conventional thermistors or thermo-
couples. Remote accuracy is ±3°C for multiple transistor
manufacturers, with no calibration needed. The remote
channel can also measure the die temperature of other
ICs, such as microprocessors, that contain an on-chip,
diode-connected transistor.
♦ Two Channels Measure Both Remote and Local
Temperatures
♦ No Calibration Required
♦ SMBus 2-Wire Serial Interface
♦ Programmable Under/Overtemperature Alarms
♦ OVERT Output for Fan Control
♦ Supports SMBus Alert Response
♦ Supports Manufacturer and Device ID Codes
The 2-wire serial interface accepts standard System
Management Bus (SMBus®) Write Byte, Read Byte, Send
Byte, and Receive Byte commands to program the alarm
thresholds and to read temperature data. The data format
is 7 bits plus sign, with each bit corresponding to 1°C, in
two’s complement format. Measurements can be done
automatically and autonomously, with the conversion rate
programmed by the user or programmed to operate in a
single-shot mode. The adjustable rate allows the user to
control the supply-current drain.
♦ Accuracy
±2°C (+60°C to +100°C, local)
±3°C (-40°C to +125°C, local)
±3°C (+60°C to +100°C, remote)
♦ 3µA (typ) Standby Supply Current
♦ 70µA (max) Supply Current in Auto-Convert Mode
♦ +3V to +5.5V Supply Range
The MAX1619 is nearly identical to the popular MAX1617A,
with the additional feature of an overtemperature alarm out-
put (OVERT) that responds to the remote temperature; this
is optimal for fan control.
♦ Write-Once Protection
♦ Small 16-Pin QSOP Package
Ord e rin g In fo rm a t io n
________________________Ap p lic a t io n s
PART
TEMP. RANGE
PIN-PACKAGE
Desktop and Notebook
Computers
Central Office
Telecom Equipment
MAX1619MEE
-55°C to +125°C
16 QSOP
Smart Battery Packs
LAN Servers
Test and Measurement
Multichip Modules
Typ ic a l Op e ra t in g Circ u it
Industrial Controls
+3V TO +5.5V
200Ω
0.1µF
___________________P in Co n fig u ra t io n
V
STBY
TOP VIEW
CC
10k EACH
V
1
2
3
4
5
6
7
8
16 N.C.
CC
MAX1619
GND
DXP
15 STBY
14 SMBCLK
13 N.C.
DXP
CLOCK
DATA
SMBCLK
SMBDATA
ALERT
DXN
N.C.
MAX1619
INTERRUPT
TO µC
DXN
12 SMBDATA
11 ALERT
10 ADD0
2N3904
2200pF
FAN
CONTROL
ADD1
GND
GND
OVERT
ADD0 ADD1 GND
9
OVERT
QSOP
SMBus is a registered trademark of Intel Corp.
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.