Rainbow Electronics MAX6635 User Manual
C-compatible serial interface, General description, Applications
General Description
The MAX6633/MAX6634/MAX6635 combine a tempera-
ture sensor, a programmable overtemperature alarm,
and an SMBus™/I
2
C™-compatible serial interface into
a single package. They convert their die temperatures
into digital values using internal analog-to-digital con-
verters (ADCs). The result of the conversion is then held
in a temperature register as a 12-bit + sign value, allow-
ing 0.0625°C resolution, readable at any time through
the serial interface. The devices are capable of reading
temperatures up to +150°C.
The MAX6633/MAX6634/MAX6635 feature a shutdown
mode that saves power by turning off everything except
the power-on reset (POR) and the serial interface. The
devices can be configured to separate addresses,
allowing multiple devices to be used on the same bus.
The MAX6633 has four address pins, allowing up to 16
devices to be connected to a single bus. The MAX6634
has three address pins, allowing up to eight devices to
be connected to a single bus. The MAX6635 has two
address pins, allowing up to four devices to be con-
nected to a single bus.
The MAX6633/MAX6634/MAX6635 make temperature
data available for transfer over the serial interface. The
MAX6634 incorporates a dual-mode
ALERT output
(open drain) and can serve as an upgraded alternative
to the LM75. The MAX6635 includes an
ALERT output
and an
OVERT output (both open drain) and can func-
tion as an upgraded replacement for the LM76 in most
applications. The MAX6634/MAX6635 feature user-pro-
grammable temperature thresholds. All three devices
come in an 8-pin SO package.
Applications
Battery Temperature Alarms
PC Temperature Control
Automotive Equipment
Features
♦ +3V to +5.5V Supply Range
♦ Accuracy
±1°C max (0°C to +50°C)
±1.5°C max (-20°C to +85°C)
±2.5°C max (-40°C to +125°C)
±2.5°C typ (+150°C)
♦ User-Programmable Temperature Thresholds
(MAX6634/MAX6635)
♦ User-Configurable Alarm Output(s)
(MAX6634/MAX6635)
♦ Ability to Respond to SMBus/I
2
C-Compatible Alert
Response Address (MAX6634/MAX6635)
♦ OVERT Output for System Shutdown (MAX6635)
♦ Multiple Devices per Bus
16 devices (MAX6633)
8 devices (MAX6634)
4 devices (MAX6635)
MAX6633/MAX6634/MAX6635
12-Bit Plus Sign Temperature Sensors with
SMBus/I
2
C-Compatible Serial Interface
________________________________________________________________ Maxim Integrated Products
1
Ordering Information
19-2120; Rev 0; 8/01
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
MAX6633MSA
-55°C to +150°C
8 SO
MAX6634MSA
-55°C to +150°C
8 SO
MAX6635MSA
-55°C to +150°C
8 SO
SMBus is a trademark of Intel Corp.
I
2
C is a trademark of Philips Corp.
V
CC
V
CC
SCL
SDA
1
5
8
2
3
TO SYSTEM
SHUTDOWN
A0 A1 GND
+3.0V TO +5.5V
0.1
µF
ALERT
OVERT
MAX6635
4
6
7
10k
Ω
1k
Ω
1k
Ω
10k
Ω
TO INTERRUPT
CONTROLLER
TO SMBus/I
2
C
MASTER
Typical Operating Circuit
Pin Configurations appear at end of data sheet.