MMS Electronics has available a new range of digital temperature sensors from Smartec BV. The SMT172 is an ultra-low power, fully calibrated, high accuracy digital sensor. Using the most recent advances in silicon temperature sensing technology, the SMT172 has applied sophisticated IC design techniques and high-precision calibration methods, to achieve an absolute inaccuracy of less than 0.25ºC in the range of -10 ºC to 100 ºC. Full temperature range is -45ºC to 130ºC. The sensor operates with a supply voltage from 2.7 to 5.5V. With a typical active current of only 60uA, high speed conversion over 4000 outputs per second (at room temperature) and extremely low noise, makes this the most energy efficient temperature sensor in the world. The SMT172 has a pulse width modulated output signal, where the duty cycle is proportional to the measured temperature. The sensor can connect directly to a Micro-processor without an Analog-to-Digital Converter. The SMT172 replaces the SMT160-30. 

link to SMT172 temperature sensors and datasheet.