A talking logic probe block diagram

The concept of a talking logic probe can be thought of as a typical testing device with a speaker. The LEDs for binary high and low status can be removed from the logic probe because of the voice synthesis feature of the digital tester. To test different digital IC families with a logic probe is very important in electronics because today's products use them extensively. Therefore, a slide switch for selecting between Transistor-Transistor Logic (TTL) and Complementary Metal-Oxide-Semiconductor (CMOS) type digital ICs is provided in the talking logic probe.

Note

CMOS devices use FETs (Field Effect Transistors) instead of Bipolar Junction transistors (BJTs) used by TTL ICs. The CMOS technology is being used in all the semiconductor devices because of lower power dissipation as compared to the TTL technologies. Also, some CMOS ICs can operate on as low as 1.8 V DC to 2.0V DC whereas TTL devices supply a voltage range between 3.75V DC to 5.75V DC.

A concept...