Circuits & Schematics - Analogue Design - 7

With linear regulators, you measure dropout voltage, V IN V OUT , at the minimum input voltage for which the IC sustains regulation. Low dropout means longer battery life, because the load circuit continues to operate while the battery discharges ...

The circuit in this Design Idea anticipates, or jumps instantly to, the final voltage of an input-signal change. It relies on the fact that the intended input signal changes exponentially with a known time constant. This circuit was adapted from a ...

A self-biasing thermistor circuit had an overall dominant thermal/ electrical time constant as small as 25 msec but had a significantly rounded response following a square (thermal) input pulse of 100 msec; the source was a pulsed blue LED. A ...

In the AGC circuit of Fig 1, a 4-quadrant analog multiplier (IC 1 ), an amplifier stage (IC 2 ), an active, full-wave rectifier (D 1 , D 2 , R 4 -R 7 , and IC 3 ), and an integrator (IC 4 ) accomplish automatic gain control of V IN ’s ...

Figure 1 is a micropower voltage-to-frequency converter. A 0 V to 5 V input produces a 0 kHz to 10 kHz output with a linearity of 0.05%. Gain drift is 80 ppm/ C. Maximum current consumption is only 90 µA, almost 30 times lower than currently ...

Analog circuits for long-term testing of passive components, such as 0.1%-tolerant resistors or high-intensity white LEDs, often require a constant current. Using two op amps and a voltage reference, you can develop a circuit that provides a ...

A typical SCR (silicon-controlled rectifier) requires a trigger current, which causes the SCR structure to latch on. Once the device latches, the current through the SCR is solely a function of external component values. The SCR has no inherent ...

The standard way of using an RTD (resistance-temperature-detector) sensor is to include it in a bridge followed by a differential amplifier. The problem is that two nonlinearities one from the sensor and another from the bridge affect the transfer ...

A resistive DAC in a resistive-feedback loop of an op amp lets you create an analog-digital-analog divider. The resistance, R WA , between the W and A terminals of the Analog Devices AD5293 (Figure 1) decreases linearly with increasing the ...

Designers often use relays as electrically controlled switches. Unlike transistors, their switch contacts are electrically isolated from the control input. However, the power dissipation in a relay coil may render the device unattractive in ...