This thermometer uses an NTC thermistor (RIO) to produce a dc voltage that decreases with temperature, to drive an I..
The circuit can control up to 6 kW of heating, with moderate gain, using a 25-amp triac (SC260D). Feedback is provided by the negative temperature co-efficient (NTC) thermistor, which is mounted adjacent to the environment being temperature controlled. The temperature set potentiometer is initially adjusted to the desired heating level. As the thermistor becomes heated by the load, its resistance drops, phasing back the conduction angle of the triac, so the load voltage is.....
In the case where analog signals are being used as the logic control, hysteresis from a Schmitt-trigger input can be used to prevent haH-wave power output. The circuit operation is as follows: at low input voltages, Q1 is biased in the off state. Q2 conducts and biases Q3, and the IRED turns off. When the base of Q1 reaches the biasing voltage of 0.6 V, plus the drop across Rv. Q1 turns on. Q3 is then supplied base drive, and the solid-state relay input will be.....
This combination sync stripper and universal video interface can solve a lot of problems for you, including Super-Nintcndo-to-anything interfacing, video overlay and scope TV frame locking. Kits, fully tested units, and custom cable assemblies are available tlirough Redmond Cable. ..
This circuit, is basically a resistance ? sensing window switch, except that the ?resistor? takes the form of an NTC thermistor and the circuit thus responds to temperature. TH1 must have a resistance in the range 500ohm - 9Kohm. RV1 is used to set half ? supply volts on the RV1 ? TH1 junction at the ?mean? temperature.
Build-in charger for instruments powered by single lithium-ion or Li-Pol accumulator. If external power supply not conected to charger, current back from the accu charger is very small. New version improved temperature stability and Not Needed NTC thermistor. After a simple adjustment can be from initial engagement to launch a thermistor to compensate for temperature dependence. After adjustment (see Figure 1 ) operates as a transistor T4 not voltage follower, but as a.....
The most common appl icat ion for the NTC thermistor
is temperature measurement. Accurate temperature
measurement can easily be accomplished by interfacing a
Wheatstone Bridge, 6K/30K ohm thermistor network and a
digital voltmeter integrated circuit as illustrated in Figure 5.
The IC consist of an analog to digital converter with built-in
3-1/2 digit LCD driver providing resolution of 0.1°C. Using
the 6K/30K ohm thermistor network makes it possible to
An 8-pin Atmel ATtiny45 microcontroller uses one of its analog-to-digital pins to measure the voltage divided between a 4700 ohm fixed resistor in series with a BC Components 2322 640 66103 NTC 10 kilohm thermistor (Digi-Key BC1482 $0.68). The thermistor changes resistance in a predictable way based on the temperature...
The Thermistor, or NTC (Negative Temperature Coefficient) of 10K, is a standard type. Most types will work. The one in the diagram is a 10K model made by Fenwal (#197-103LAG-A01). The resistance lowers as the surrounding temperature increases which affects the output (pin 6) and energizes the small relay and Led1(optional, just cosmetic and can be left out). P1 is a regular Bourns trimmer potentiometer and adjusts a certain range of temperatures. I used a 50K, 10-turn.....
Microchip Technology (www.microchip.com) offers a family of cooling-fan speed controllers that operate in PWM mode for use with brushless dc fans (Reference 1). To control fan speed using the PWM waveform`s duty cycle, you can use either an external NTC (negative-temperature-coefficient) thermistor or one of Microchip`s PIC microcontrollers and its SMBus serial-data bus. Figure 1 illustrates a typical application that the data sheet describes for the TC664 and TC665.....
This digital thermometer with 7 LEDs on the temperature measured with a NTC. The circuit works by using an opamp, the known 741 that the voltage difference between its positive and negative input strengthened. This gain (sensitivity) can be set P2. With P1, the bridge of P1 and R1 be adjusted...
The simplest of all motor controllers (besides a straight on/off switch) is the contactor controller. I designed this contactor controller for use in my electric scooter project. It is based around three 12V relays, two 12V batteries, two switches and of course a motor. Having no silicon to "fry", it is quite reliable and robust. A contactor controller works by rearranging the two (or more) supply batteries between series and parallel. This gives the motor a slow speed.....
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