Circuits & Schematics - Interfaces - 2

This Design Idea is an evolution and simplification of another (Figure 1, Reference 1 ). Replacing the three inverted-input NOR gates with their logical equivalents, positive-input NAND gates, makes these three gate symbols consistent with the ...

The control of electronic potentiometers in most today's applications comes from controller-generated signals. However, a significant number of applications exist that require adjustments using manual, front-panel controls. The circuit in ...

You typically accomplish overvoltage or surge protection at circuit inputs by connecting diodes to the supply rails, connecting zener diodes to ground, or connecting transzorbs to ground. Unfortunately, for high-energy surges at the inputs, ...

AC signals can emanate from many sources, and many of these sources are incompatible with the most popular interface voltages, such as TTL. A temptation always exists to capacitively couple the ac signals because capacitive coupling strips off the ...

By combining the responses of AD590 temperature sensor and a HS1101 humidity sensor, you can generate a single TTL-level signal containing information from both sensors (Figure 1). This design uses a 74HC123 monostable multivibrator, IC 1 , to form ...

In some applications of capacitive sensors, the instrument’s front end must be small enough to fit into a narrow space. Figure 1 shows a precision capacitive-sensor interface for such use. The square-wave output from a low-voltage 555 timer, ...

Interfacing two systems that operate at two arbitrary voltages is a challenging problem; there is no guarantee that one side operates at a voltage higher than the other side. Usually, the interface is an open-collector or open-drain type with just ...

A USB port offers a handy source of 5 V power for auxiliary devices. A USB port not only supplies power to a microcontroller and other essential circuitry, but also provides enough extra current head room to charge a small battery or supercapacitor ...

You can use a microcontroller that includes an ADC to design a two-wire-plus-ground keyboard interface. For example, you can use a resistive voltage divider to identify a pressed key (Reference 1). A microcontroller's integrated ADC typically ...

The best way to make midrange, low- to medium-accuracy temperature measurements (considering size, cost, performance, and ease of use) is to use an IC temperature sensor. But most IC temperature sensors are designed for applications where the ...