Sawtooth Generator Exhibits ~ 1
Abstract: Two integrated circuits (ICs) and some associated components form a voltage-controlled sawtooth generator that costs less than $ 3 and produces an auxiliary square wave at the same frequency. The generator is useful in a variety of applicaTIons. Its sawtooth waveform is commonly used, for example, to sweep the frequency of another generator.
Two ICs and some associated components (Figure 1) form a voltage-controlled sawtooth generator that costs less than $ 3 and produces an auxiliary square wave at the same frequency. The generator is useful in a variety of applicaTIons. Its sawtooth waveform is commonly used, for example, to sweep the frequency of another generator.
Figure 1. This simple voltage-controlled sawtooth-waveform generator operates with a linearity of 1% or less. A second output provides a square wave of the same frequency.
IC1 with Q1 and R1 forms a voltage-controlled current source. Current I0 discharges C1 unTIl the C1 voltage is less than 1.66V, which trips the IC2A comparator and swings its output to 5V. Current through the diode-connected transistor (Q2) charges C1 unTIl its voltage reaches 3.33V, causing the IC2A output to swing back to ground. This repeating cycle determines the output frequency:
fOUT = (3 (5V + VC) / 5V) (1 / R1C1).
The maximum fOUT occurs when VC = 1.66V, but fOUT can be set as high as desired by adjusting the values ​​of R1 and C1, subject to the limitations of comparator IC2A's slew rate and settling time. The MAX991 (as IC2A) yields a rise time of 150ns when a 3300pF load (C1) is present at its output. Lower C1 values ​​yield shorter rise times, which allow higher fOUT. When fOUT approaches its maximum, the finite tr degrades the VCO linearity somewhat. By careful selection of R1 and C1, this effect will be minimized and linearities of 1% or better can be achieved.
The generator's linearity determines the frequency range over which it can operate. This generator's good linearity performance allows it to operate across several decades of frequency.
A similar version of this article appeared in the July 26, 1999 issue of Electronic Design magazine.
Bare aluminium conductors have several advantages over other types of conductors. Firstly, aluminium is lighter than copper, which makes it easier to handle and install. This is particularly important for overhead power lines, where the weight of the conductor can have a significant impact on the cost and feasibility of the project.
Secondly, aluminium has a higher conductivity-to-weight ratio than copper. This means that for a given weight, aluminium conductors can carry more current than copper conductors. This makes them more efficient in terms of power transmission.
However, bare aluminium conductors also have some disadvantages. One major drawback is their lower mechanical strength compared to copper conductors. This makes them more susceptible to sagging and stretching under the weight of their own span, especially in hot weather conditions. To address this issue, aluminium conductors are often reinforced with steel strands to improve their mechanical strength.
Another disadvantage is that aluminium has a higher resistance than copper, which can result in higher power losses and voltage drops. To mitigate this, aluminium conductors are typically designed with larger cross-sectional areas compared to copper conductors to compensate for the higher resistance.
Overall, bare aluminium conductors are widely used in electrical power transmission and distribution systems due to their cost-effectiveness, lightweight, and high conductivity-to-weight ratio. However, careful design and installation considerations are necessary to ensure their mechanical strength and minimize power losses.
Two ICs and some associated components (Figure 1) form a voltage-controlled sawtooth generator that costs less than $ 3 and produces an auxiliary square wave at the same frequency. The generator is useful in a variety of applicaTIons. Its sawtooth waveform is commonly used, for example, to sweep the frequency of another generator.
Figure 1. This simple voltage-controlled sawtooth-waveform generator operates with a linearity of 1% or less. A second output provides a square wave of the same frequency.
IC1 with Q1 and R1 forms a voltage-controlled current source. Current I0 discharges C1 unTIl the C1 voltage is less than 1.66V, which trips the IC2A comparator and swings its output to 5V. Current through the diode-connected transistor (Q2) charges C1 unTIl its voltage reaches 3.33V, causing the IC2A output to swing back to ground. This repeating cycle determines the output frequency:
fOUT = (3 (5V + VC) / 5V) (1 / R1C1).
The maximum fOUT occurs when VC = 1.66V, but fOUT can be set as high as desired by adjusting the values ​​of R1 and C1, subject to the limitations of comparator IC2A's slew rate and settling time. The MAX991 (as IC2A) yields a rise time of 150ns when a 3300pF load (C1) is present at its output. Lower C1 values ​​yield shorter rise times, which allow higher fOUT. When fOUT approaches its maximum, the finite tr degrades the VCO linearity somewhat. By careful selection of R1 and C1, this effect will be minimized and linearities of 1% or better can be achieved.
The generator's linearity determines the frequency range over which it can operate. This generator's good linearity performance allows it to operate across several decades of frequency.
A similar version of this article appeared in the July 26, 1999 issue of Electronic Design magazine.
Bare aluminium conductors are electrical conductors made from pure aluminium. They are used in various electrical applications, including overhead power transmission and distribution lines.
Bare aluminium conductors have several advantages over other types of conductors. Firstly, aluminium is lighter than copper, which makes it easier to handle and install. This is particularly important for overhead power lines, where the weight of the conductor can have a significant impact on the cost and feasibility of the project.
Secondly, aluminium has a higher conductivity-to-weight ratio than copper. This means that for a given weight, aluminium conductors can carry more current than copper conductors. This makes them more efficient in terms of power transmission.
However, bare aluminium conductors also have some disadvantages. One major drawback is their lower mechanical strength compared to copper conductors. This makes them more susceptible to sagging and stretching under the weight of their own span, especially in hot weather conditions. To address this issue, aluminium conductors are often reinforced with steel strands to improve their mechanical strength.
Another disadvantage is that aluminium has a higher resistance than copper, which can result in higher power losses and voltage drops. To mitigate this, aluminium conductors are typically designed with larger cross-sectional areas compared to copper conductors to compensate for the higher resistance.
Overall, bare aluminium conductors are widely used in electrical power transmission and distribution systems due to their cost-effectiveness, lightweight, and high conductivity-to-weight ratio. However, careful design and installation considerations are necessary to ensure their mechanical strength and minimize power losses.
Aluminium Bare Stranded Conductors,Bare Aluminium Conductors,Overhead Transmission Line, Transmission line Bare Aluminium Conductors
Ruitian Cable CO.,LTD. , https://www.rtpowercable.com