Long Interval Pulse Generator Circuit Diagram

Long-Interval Pulse Generator Circuit Diagram. A rectangular-wave pulse generator with an extremely long period can be built using only two components: a National Semiconductor LM3710 supervisor IC and a 100-nF capacitor to eliminate noise spikes. This circuit utilises the watchdog and reset timers in the LM3710. The watchdog timer is reset when an edge appears on the WDI input (pin 4). If WDI is continuously held at ground level, there are not any edges and the watchdog times out. After an interval TB, it triggers a reset pulse with a duration TA and is reloaded with its initial value. The cycle then starts all over again. As a result, pulses with a period of TA + TB are present at the RESET output (pin 10).

Long-Interval Pulse Generator Circuit Diagram

Long-Interval Pulse Generator Circuit Diagram

As can be seen from the table, periods ranging up to around 30 seconds can be achieved in this manner. The two intervals TA and TB are determined by internal timers in the IC, which is available in various versions with four different ranges for each timer. To obtain the desired period, you must order the appropriate version of the LM3710. The type designation is decoded in the accompanying table.

The reset threshold voltage is irrelevant for this particular application of the LM3710. The versions shown in bold face were available at the time of printing. Current information can be found on the manufacturer’s home page (www.national.com). The numbers in brackets indicate the minimum and maximum values of intervals TA and TB for which the LM3710 is tested. The circuit operates with a supply voltage in the range of 3–5 V.

Author: Gregor Kleine Copyright: Elektor Electronics

Comments

3 Channels Audio Splitter Amplifier Circuit Diagram using TL084

This is the schematic diagram of 3 channels audio splitter amplifier circuit which built using op-amp IC TL084. The 3 channels amplifier output distribution applies a single TL084. 3 Channels Audio Splitter Amplifier Circuit Diagram The very first step is to capacitive coupling having a p. 1.0 ~ electrolytic capacitor. The entries are railways Vee Y2 or 4.5 V. This enables working with an individual 9V power source. A voltage gain of 10 (1 M?/100 Kohm) is obtained in the first stage, as well as the other three floors are connected as a unity gain voltage followers. Every single output stage drives independently through an amplifier output 50 pF capacitor towards the resistance of 5.1 k ohm load. The response range is flat from 10 Hz to 30 kHz.

Simple But Automatic Load Sensing Power Switch

This circuit will automatically switch on several mains-powered "slave" loads when a "master" load is turned on. For example, it will switch on the amplifier and CD player in a stereo system when the receiver is turned on. It works by sensing the current draw of the "master" device through a low value high wattage resistor using a comparator. The output of that comparator then switches on the "slave" relay. The circuit can be built into a power bar, extension cord or power center to provide a convenient set of "smart" outlets that switch on when the master appliance is powered (turn on the computer monitor and the computer, printer and other peripherals come on as well). Automatic Load Sensing Power Switch Circuit Diagram Parts List: Notes: This circuit is designed for 120V operation. For 240V operation, resistors R2 and R6 will need to be changed. A maximum of 5A can be used as the master unless the wattage of R1 is increased S1 provid...

RF amplifier protection

RF amplifier protection I have developed the protection circuit for the EB104 amplifier I am working on, after I finally had some time to design and test a few models. The main requirements have been: - protection in case of high temperature; - protection in case of high SWR; - protection in case of wrong output filter selection; - simple design (i’m a fan of the whole K.I.S.S. rule of thought), able to work in strong electromagnetic fields, reliable, inexpensive. Because i will be using the same directional coupler i have used in the SWR meter (the one made on PCB) wich is directly influenced by the signal frequency, and because i want full HF coverage, i cannot just measure the reflected signal and make a circuit cut the amplifier when it goes over a limit; on 28Mhz the coupler generates roughly 4 times more voltage that let’s say in 7Mhz. So a system that compares direct and reflected signal and triggers when the latter is percentually too high was needed, therefore an operational a...

TREE

Search This Blog