LM75 is a digital emperature sensor which has I2C interface feature. This sensor can be easily interfaced to PSoC 1 for temperature measurement.
I2CHW User Module in PSoC 1 can be used for this purpose. This module acts as I2C master and communicates with the slave I2C device, which is the sensor here.
A PSoC Designer project in which this is implemented is attached along with a document which explains the implementation.