1FEATURES
234• SOT23-8 and DSBGA (WCSP) PACKAGES
• ±1°C REMOTE DIODE SENSOR (MAX)
• ±1.5°C LOCAL TEMPERATURE SENSOR (MAX)
• SERIES RESISTANCE CANCELLATION
• n-FACTOR CORRECTION
• TWO-WIRE/ SMBus™ SERIAL INTERFACE
• MULTIPLE INTERFACE ADDRESSES
• DIODE FAULT DETECTION
• RoHS COMPLIANT AND NO Sb/Br

APPLICATIONS
• PROCESSOR/FPGA TEMPERATURE
MONITORING
• LCD/ DLP®/LCOS PROJECTORS
• SERVERS
• CENTRAL OFFICE TELECOM EQUIPMENT
• STORAGE AREA NETWORKS (SAN)

DESCRIPTION
The TMP421, TMP422, and TMP423 are remote
temperature sensor monitors with a built-in local
temperature sensor. The remote temperature sensor
diode-connected transistors are typically low-cost,
NPN- or PNP-type transistors or diodes that are an
integral part of microcontrollers, microprocessors, or FPGAs.
Remote accuracy is ±1°C for multiple IC
manufacturers, with no calibration needed. The two-
wire serial interface accepts SMBus write byte, read
byte, send byte, and receive byte commands to
configure the device.
The TMP421, TMP422, and TMP423 include series
resistance cancellation, programmable non-ideality
factor, wide remote temperature measurement range
(up to +150°C), and diode fault detection.
The TMP421, TMP422, and TMP423 are all available
in a SOT23-8 package. The TMP421C is also
available in a DSBGA (WCSP) package.