The TMP03/TMP04 are monolithic temperature detectors that
generate a modulated serial digital output that varies in direct
proportion to the temperature of the device. An onboard sensor
generates a voltage precisely proportional to absolute temperature
which is compared to an internal voltage reference and
input to a precision digital modulator. The ratiometric encoding
format of the serial digital output is independent of the clock drift
errors common to most serial modulation techniques such as
voltage-to-frequency converters. Overall accuracy is ±1.5°C
(typical) from –25°C to +100°C, with excellent transducer linearity.
The digital output of the TMP04 is CMOS/TTL
compatible, and is easily interfaced to the serial inputs of most
popular microprocessors. The open-collector output of the
TMP03 is capable of sinking 5 mA. The TMP03 is best suited
for systems requiring isolated circuits utilizing optocouplers or
isolation transformers.
The TMP03 and TMP04 are specified for operation at supply
voltages from 4.5 V to 7 V. Operating from 5 V, supply current
(unloaded) is less than 1.3 mA.
The TMP03/TMP04 are rated for operation over the –40°C to
+100°C temperature range in the low cost TO-92, SO-8, and
TSSOP-8 surface mount packages. Operation extends to 150°C
with reduced accuracy.