It’s rare to see breadboard friendly I2C sensors, but this TO-220 package with 5 pins is, in fact, such a thing! It’s a basic temperature sensor, not the highest precision in the world, only ±2°C but it will get the job done when you need simple temperature logging or monitoring.
Wiring it up is easy, pin 2 is SDA, middle pin is GND, pin 4 is SCL and the rightmost pin 5 is VDD. You can power it with 3.3 or 5V logic so it’s good for any microcontroller or microcomputer. Note you will need to add I2C pull-ups on your breadboard especially if your I2C controller does not have them built in already
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I have found that the TC74A is not completely I2C compatible, and you may have trouble using it with some processors. The I2C specification requires a data hold time for I2C devices of 0 ns, but the TC74A datasheet specifies a minimum hold time of 1250 ns. If a microcontroller has an I2C interface that is designed to operate up to 1 MHz (Fast-mode Plus) then a hold time of 1250 ns is longer than the SCLK period, so it doesn’t surprise me that a fast microcontroller would provide a data hold time much, much less than 1250 ns.
I have found that the TC74A is not completely I2C compatible, and you may have trouble using it with some processors. The I2C specification requires a data hold time for I2C devices of 0 ns, but the TC74A datasheet specifies a minimum hold time of 1250 ns. If a microcontroller has an I2C interface that is designed to operate up to 1 MHz (Fast-mode Plus) then a hold time of 1250 ns is longer than the SCLK period, so it doesn’t surprise me that a fast microcontroller would provide a data hold time much, much less than 1250 ns.