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LM555 Voltage Doubler - del50007

This circuit shows the voltage doubler working with a 555. LM555 has good drive 200mA, both Vcc and Gnd. This is a simple voltage doubler using a 555, this can help boosting a low battery voltage to power a logic or opamp circuit.

Using LEDs with Battery Power - Here you can learn about LED and how to use them.

555 has the advantage of having a high drive as well as being a Mixed Design, Analog Programmable chip. That may be a High Title for such humble a chip.

It has the capability of a Mini ADC due to its VCO function. It could form even a simple switching supply. Power Line Modems have been designed using this chip.

Voltage Doublers and Multipliers - Diodes and Caps can boost voltage for low power(current) applications.

Voltage multipliers can be used to generate bias voltages of a few volts or tens of volts or millions of volts for purposes such as high-energy physics experiments and lightning safety testing."   I drew this for a person who makes toys.

LM555 Voltage Doubler

Timers, Modulators, Trip Relays and even a Timer for The Humble Bread Toaster. Musical circuits, Piano and Metronome Galore, it drives Speakers directly. 555 does most everything !

The Star of what we used to Know as Chip as IC. Too small today in the days of ASIC and FPGA. But ideal for Education of Electronics and Simple Real times Solutions.

Microohm Meter with LED Analog Bar

In this circuit a 555 is used to get a Negative Supply from a 9V battery for a portable measurement device.

Negative Voltage with 555

+5 to -5 using a 555 Astable Multivibrator

This is a very simple -5V supply using one 555, useful for analog blocks using FET Opamps using low power. This circuit came up when i had to design limited by inventory. It worked well for its need. It converts Positive Five Volts to Negative Five Volts to create a dual supply.

            Supply from 555

This +5 to -5 using a 555 Astable not a high efficiency design, in fact it cannot take a heavy load. Circuits having some CMOS Opamps and a A/D convertor is ok. Even very small battery designs must avoid this circuit.

This suits well when you want to power an analog amp which has to measure voltages which swing on either sides of zero. It can be used in a LCD based portable measuring instrument running on a rechargeable 9V battery.

Powering a strain gauge amp may be one use, another may be like a RTD temperature meter for -50 to +150 deg C.

Threshold Voltage

On trigger at pin 2, Output goes high, timing cap charges from 0 to 2/3 Vcc the pin 6 of an internal comparator senses it & trips. Pin 7 goes low discharging the cap. Pin 3 goes low too. This ends the Timing Cycle. Mixed Signal Chip - The 1/3 and 2/3 analog voltage levels can control the operation of the 555 pip 3 Digital output Level. Use a 7555 CMOS 555 to get a CMOS Digital Compatible output.

              Voltage 555

Time Delay Power off

This circuit uses the two internal 1/3 and 2/3 comparators to create a Time delay switch. The output driver with two NPN is interesting as it inverts output. That is when pin 3 goes high Q1 say BC147 turns on shutting off Q2 by zeroing its base. Q2 could be BD139 and can drive a bigger load. When 3 goes low.. Q1 stops conducting and Q2 gets bias from R2 and Turns on the load. Use a 4.7K resistor from Pin 3 to protect output.

The circuit design seems to be by a creative French Artist, it probably needed a Englishman to do a Design Review. We need people from all countries to make Electronics Colorful yet practical.

Time Delay Power

Images above are from the Original Signetics 555 Datasheet

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20th Apr 2020


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