Circuits & Schematics - 4

The circuit in Figure 1 serves as a variable, current-sink load for testing voltage sources. You use digital commands to set the load current of the device under test over a wide range, independently of the device under test's output voltage. ...

The circuit in Figure 1 uses the LM358 dual op amp running as a comparator, plus a few other inexpensive components, to make a TTL (transistor- transistor-logic)/CMOS-logic probe. The circuit gets its power from the circuit under test, which lets ...

The thermocouple is a popular sensor for industrial temperature measurement because it's accurate, cost-effective, widely available, and suitable for a wide range of temperatures. It consists of two wires of different metal or metal alloys, ...

The circuit in Figure 1 derives its power from a USB port and produces 5 and 3.3 V supply rails for portable devices, such as digital cameras, MP3 players, and PDAs. The circuit allows the port to maintain communications while, for example, ...

Instrumentation amplifiers serve in a variety of applications that need to extract a weak differential signal from large common-mode noise or interference. However, designers often overlook the potential problem of RF rectification inside the ...

This Design Idea describes an enhancement to a previous one ( Reference 1 ). The circuit in Figure 1 uses a normally open SPST pushbutton switch, S 1 , instead of the SPDT switch that the original design required. You can use a membrane switch to ...

I recently needed to control nine seven-segment displays for a microcontroller's serial port. The complication I faced was the need to provide a continuous brightness adjustment for all the digits from completely dark to fully bright. I ...

This Design Idea presents a low power short circuit finder that capitalizes on the ear’s sensitivity to changes in frequency. The heart of the circuit is a voltage-to-frequency converter (based on Ref. 1, Figure 13), which converts ...

The Texas Instruments IVC102 precision integrator has high-quality internal capacitors. The circuit in Figure 1 allows you to measure very-high-resistance values of R X . A precision difference amplifier, a TI INA105 , applies a reference voltage ...

In dc/dc-converter applications in which the input voltage may be lower or higher than the output voltage, you can use either a flyback converter or a SEPIC (single-ended-primary-inductor converter). SEPICs offer lower input-current ripple and ...