MIC281_14 Datasheet, PDF (1/14 Pages) Micrel Semiconductor – Low-Cost IttyBitty™ Thermal Sensor

MIC281
Low-Cost IttyBitty™ Thermal Sensor
General Description
The MIC281 is a digital thermal sensor capable of
measuring the temperature of a remote PN junction. It is
optimized for applications favoring low cost and small size.
The remote junction may be an inexpensive commodity
transistor, e.g., 2N3906, or an embedded thermal diode
such as found in Intel Pentium^® II/III/IV CPUs, AMD
Athlon^® CPUs, and Xilinx Virtex^® FPGAs.
The MIC281 is 100% software and hardware backward
compatible with the MIC280 and features the same
industry-leading noise performance and small size. The
advanced integrating A/D converter and analog front-end
reduce errors due to noise for maximum accuracy and
minimum guardbanding.
A 2-wire SMBus 2.0-compatible serial interface is provided
for host communication. The clock and data pins are 5V-
tolerant regardless of the value of V_DD. They will not clamp
the bus lines low even if the device is powered down.
Superior performance, low power, and small size make the
MIC281 an excellent choice for cost-sensitive thermal
management applications.
Datasheets and support documentation are available on
Micrel’s website at: www.micrel.com.
Features
 Remote temperature measurement using embedded
thermal diodes or commodity transistors
 Accurate remote sensing: ±3°C max., 0°C to 100°C
 Excellent noise rejection
 I²C and SMBus 2.0-compatible serial interface
 SMBus timeout to prevent bus lockup
 Voltage tolerant I/Os
 Low power shutdown mode
 Failsafe response to diode faults
 3.0V to 3.6V power supply range
 Available in IttyBitty SOT23-6 package
Applications
 Desktop, server, and notebook computers
 Set-top boxes
 Game consoles
 Appliances
Typical Application
IttyBitty is a trademark of Micrel, Inc. All other trademarks are the property of their respective owners.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
April 23, 2014
Revision 2.0