Input 1 is used as a gating period, during which a single rising edge on input 2 will cause a logic 1 output-any other number, indicating non-identical frequencies causes a logic 0 output. ICla converts input 1 to a narrow pulse which initializes IC2 which forms a two-stage shift register clocked by input 2. On the first edge of input 2 a logic 1 appears on the output of IC2b and for all subsequent inputs a logic 0 is present. At the end of the gating period this output is.....
The logic probe can indicate four input states, as follows: floating input—all LEDs off..
The logic input is applied to opto-isolators Ul and U2 with, respectively, npn and pnp emitter follower outputs. Dc balance is adjusted by potentiometer R2. The emitter followers drive the gates of Ql and Q2, the complementary TMOS pairs. With a ±12 V supply, the swing at the common source output point is about 12 V peak-to-peak. By adding a ± 18-V boost circuit, as shown, the output swing can approach the rail swing. ..
The very simple circuit uses only two CD4001 packages, i.e., eight NOR gates and operates in the following way: Pulse streams are fed to an RS flip flop generating an output waveform wliich has a small or large duty cycle depending on the direction of rotation, The same input pulses are also fed to a NOR gate, which adds the two pulse trains. The rising edges of this waveform are used to produce short positive pulses from the circuit consisting of Rl, CI, D3, and a NOR.....
The single transistor connected between the capacitor and the common side of the ac line allows a logic-level signal to control this triac power circuit...
The circuit uses a dual LED. When power is applied to the probe throughthe power leads, and the input is touched to a low level or ground, Ql is cut off. This will cause Q2 to conduct since the base is positive with respect to the emitter. With Ql cut off and Q2 conducting, the green diode of the dual LED will be forward biased, yielding a green output. Touching the probe tip to a high level will cause Ql and Q2 to complement, and the red diode will be forward biased,.....
These circuits illustrate some of the common logic functions..
This constant gain, constant Q, variable frequency filter provides simultaneous low-pass, bandpass, and high-pass outputs with the component values shown, the center frequency will be 235 Hz and 23.5 Hz for high and low logic inputs. ..
An optoelectronics device is used to couple a digital (TTL) signal to another system. The photodiode in the optocoupler drives an LM311 set up to produce a TTL compatible output...
When the probe is in contact with a TTL low (0) the probe emits a low note. With a TTL high (1), a high note is emitted..
Dc power can also be controlled via fiberoptics. The circuit provides an insulated speed control path for a small dc actuator motor (< Vn hp). Control logic is a self-contained module requiring about 300 mW at 12 V, which can be battery powered. The control module furnishes infrared pulses, at a rate of 160 Hz, with a duty cycle determined by the position of the speed adjust potentiometer. The programmable unijunction multivibrator provides approximately 10 mA pulses to.....
Zener diode ZD1 senses the supply, and should the supply rise above 6 V, Ql will turn on. In turn, Q2 conducts clamping the rail. Subsequent events depend on the source supply. It will either shut down, go into current limit or blow its supply fuse. None of these will damage the TTL chips..
False alarms produced by semiconductor failure are impossible with this burglar-alarm circuit equipped with relays. What"s more, the circuit is virtually immune to false triggering. With a standby current of less than 0.1 mA, the circuit offers all the features an alarm needs: entry and exit delays, a timed alarm period, and automatic reset after an intrusion. One CMOS CD4093B quad NAND gate, IC1, supplies both logic and analog timing functions with the aid of.....
The low Rds and high peak current capability ofthe DG419 makes it ideal for discharging an·integrator capacitor. A high logic input pulse disconnects the integrator from the analog input and discharges the capacitor. ..
The circuit will operate reliably from below 1 MHz to above 400 MHz. With Vcc = 5 V the output of the second inverter essentially attains a full swing from 0 V to 5 V. Such large logic output levels and broad frequency range capabilities make this oscillator quite suitable for driving MOS components such as CPU, controller chip, peripheral devices, as well as other TTL products...
The control of both direction and of proportional motor speed is achieved by rotation of a single potentiometer. The motor driver is an SGS integrated circuit L293 which will drive up to 1 amp in either direction, depending on the logic state of input 1 and input 2 as per table. I/P 1 I/P 2 Function. High Low Motor turns one way. Low High Motor reverses. By applying a variable M/S ratio flip-flop to these inputs, both speed and direction will be controlled. With RV1 in its.....
This circuit gives a 3 phase square-wave output for a variable speed motor drive. Operation is straightforward, the 4017 counter is synchronously reset after six clock inputs. The she outputs are combined to give the required waveforms. It is interesting to note that although NOR gates are shown, OR gates will give effectively the same result...
Using this simple resistor circuit, you can trick your oscilloscope into displayin..
The logic pulser generates pulses at 500 Hz or 0.5 Hz. When the pulser`s.tip connects to an input that is already being driven high or low, the pulser senses thelogic state and automatically pulses the input..
This probe makes possible relative measurements of rf voltages to 200 MHz on a 20,000 ohms-per-volt multimeter..
Operational Amplifiers
Computer Systems
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Sensors & Detectors
ANSI Standards
Low Frequency Amplifiers
Power Amplifiers
Number Systems
Regulated Power Supplies
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