Circuits & Schematics - 9

Zeroing out temperature variations on a production line is a challenging task when the device to be compensated has a temperature coefficient that varies in both magnitude and sign from unit to unit. This simple circuit can meet the challenge (see ...

I was surprised recently when a (nearly) two-decade-old design idea of mine for take-back-half temperature control ( Ref. 1 ) got a question from reader John Louis Waugaman. John says he needs a way to control the temperature of batches of rising ...

The excellent linearity of integrated-circuit temperature sensors makes them ideal for direct analog compensation of the thermally induced errors inherent in many circuits. For example, a negative-sloped temperature sensor could compensate for an ...

As a genre, DACs are low power devices with power and current output capabilities limited to the milliwatt and milliampere range. There is, of course, no fundamental reason they can’t be teamed up with suitable power output stages, which is ...

A two-terminal current source using the basic circuit of Figure 1a can be enhanced by adding on an independent subcircuit that uses degeneration of a PNP transistor to achieve zero temperature coefficient (tempco or TC). This low-cost design is the ...

A common technique for implementing PWM involves comparing a triangular waveform of fixed amplitude and frequency with a variable dc voltage level. Although this approach results in a PWM signal of precise frequency and with duty cycle variable ...

Usually, noise annoys. Occasionally, it can be a valuable tool. Surprisingly, there is a whole palette of noise colors [ 1 ]. This design idea (DI) shows good ways of generating the commonest and most useful ones, which are white [ 2 ] and pink [ 3 ...

Implementation details Loop area R1/C1/R3 should be minimized for best EMI rejection (Figure 3). Additionally, R1/C1 should be very well shielded from electrical fields, which will be discussed further in the EMI Considerations section. Although ...

The oscillator was intended for other purposes, but unexpectedly its breadboard prototype became in great demand for evaluating the performance of operational amplifiers purchased on well-known Internet sites. The simplest test of the op amp ...

Noise in electrical circuits is typically the enemy, and any self-respecting circuit should output as little noise as possible. Nevertheless, there are cases where a well-characterized source of noise with no other signal is entirely the desired ...