BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to electrical and electronic systems wherein applications with higher level of operating voltage requirements can be fulfilled with low voltage level sources.
2. Description of Related Art
A Light-Emitting-Diode (LED) is a semi-conductor device that has a certain forward voltage drop that needs to be overcome by an electrical source before it can glow. Proper operation of LED requires a supply voltage of 3V-5V. Said invention can make a LED emit light at lower supplied voltages which can be in the range of 1 to 1.5V. Said invention can be used to charge capacitors and re-chargeable batteries to voltages higher than the source or supplied voltage.
Existing DC-DC boost converters are complicated and expensive to implement. Said invention is more economic and simpler. Low frequency AC signals can be amplified by using said invention with use of a small DC biasing voltage and no additional biasing components. Existing applications that use conventional amplifiers require high level DC biasing voltage along with some additional components.
SUMMARY OF THE INVENTION
The present invention boosts low voltage level of a supplied signal to a high voltage level. However, said invention may not retain the frequency of the said supplied signal. Whether it retains signal frequency or not, depends on values of the electronic components used. It uses a combination of an electronic oscillator circuit and a clamper circuit. A clamper circuit raises voltage level of a supplied AC signal by a factor of an integer. In said invention, this AC signal is supplied by said oscillator circuit.
The present invention works on “shifting ground” principle. It creates a new GND terminal in an electrical circuit. The input and output terminals remain common.
Main applications of said invention are to drive LEDs and charge capacitors in a circuit to high voltage levels using a low voltage source. Plurality of said inventions can be used in cascade with each other to achieve much higher output voltage levels than supplied input voltage levels.
DETAILED DESCRIPTION OF INVENTION DRAWINGS
FIG. 1. shows generic block diagram of said invention. It consists of an oscillator cascaded with a clamper circuit that consists of diodes and electrical energy storing passive components such as inductors and capacitors. Diodes having low forward voltage drop such as germanium or Schottky are preferred. For current driven applications, an optional diode can be used to feedback from the output to the ground terminal of the source as shown by number 1 in the figure. An optional capacitor can be used at the output to reduce the ripples caused by the oscillator circuit as shown by number 2 in the figure.
FIG. 2. illustrates a detailed circuit diagram of an oscillator circuit using transistors (as shown by number 1 in the figure) and clamper circuit using a series of diodes (preferably Schottky or Germanium diodes as shown by number 3 in the figure) and electrolytic capacitors (as shown by number 2 in the figure) connected in a specific array. When an electrical source is applied across the ‘COM’ and ‘GND’ terminals, an AC signal is generated by the oscillator which is applied to the input of the clamper circuit. The clamper circuit raises positive peak voltage level of the AC signal generated by the oscillator. Hence, a higher potential difference is achieved and should be measured between the ‘COM’ and ‘−Vo’ terminals of the circuit.
An alternative approach for said oscillator circuit is shown in FIG. 3. An integrated circuit 555 along with some supporting components is used to generate an AC signal. LMC555CN integrated circuit is used to generate oscillating signal. It requires less power for operation thereby making it useful for low voltage input operations. Input signal is applied across ‘COM’ and ‘GND’ terminals of the circuit. Clamper circuit is the same. Numbers 2 and 3 in the figure depict capacitors and diodes respectively. A higher voltage level output can be measured across ‘COM’ and ‘−Vo’ terminals.
Like 555, any OPAMP (operational amplifier) can also be used to achieve the oscillator functionality. In FIG. 4. an OPAMP integrated circuit is used as an oscillator for AC signal generation. Remainder of the concept is the same as previously illustrated in circuit diagrams from FIGS. 2 and 3. Numbers 2 and 3 in FIG. 4 depict capacitors and diodes respectively.
FIG. 5. illustrates an integrated circuit of said invention wherein circuits from FIG. 2, 3 or 4 can be manufactured into a single 3-pin component. A source voltage can be applied across ‘COM’ (depicted by number 1 in FIG. 5) and ‘GND’ (depicted by number 2 in FIG. 5) terminals and output voltage can be drawn across the ‘COM’ and ‘−Vo’ (depicted by number 3 in FIG. 5) terminal of the integrated circuit.
A circuit symbol shown in FIG. 6. can be used to represent the invention in circuit diagrams. The first half of the figure with a square and a small signal inside it represents an oscillator. Whereas the second half of the figure resonates with an electrical capacitance circuit symbol to represents a clamper circuit. The ‘COM’ terminal in FIG. 5 corresponds to the ‘C’ terminal in FIG. 6. The ‘GND’ terminal in FIG. 5 corresponds to the ‘G’ terminal in FIG. 6. The ‘−Vo’ terminal in FIG. 5 corresponds to ‘V’ terminal in FIG. 6.
FIG. 7. illustrates the use of circuit symbol from FIG. 6. in a circuit diagram. It shows the connectivity between a signal source, said invention and load. In this figure a DC source ‘Vin’ is applied between ‘C (common)’ and ‘G (ground)’ terminal. A load resistance ‘RL’ is connected between ‘C (common)’ and ‘V (output)’ terminal. ‘C1 (capacitor)’ component helps in getting rid of any ripples in the output voltage and ‘D1 (diode)’ component is used in case the load is current driven. Both ‘C1’ and ‘D1’ are optional components. ‘Vo’ is the output voltage across the load resistance ‘RL’.
FIG. 8. shows a variation of the integrated circuit in FIG. 5. This variation of the integrated circuit opens more terminals from the damper part of the circuit. PIN-1 (as depicted by number 4 in FIG. 8) and PIN-2 (as depicted by number 6 in FIG. 8) are additional terminals of the invention that can be used to connect capacitors or inductors as per output current and voltage requirements. Numbers 1, 2, 3 and 5 in FIG. 8 depict ‘COM’, ‘−Vo’, ‘NC’ and ‘GND’ pins of the integrated circuit.
FIG. 9. is a circuit symbol of integrated circuit variation discussed for FIG. 8 in the above paragraph. The ‘V’ terminal in the symbol in FIG. 9 is same as the ‘−Vo’ terminal in FIG. 8. The ‘C’ terminal in FIG. 9 is the same as ‘COM’ terminal in FIG. 8. The ‘V’ terminal in FIG. 9 is the same as ‘−Vo’ terminal is FIG. 8. The ‘G’ terminal in FIG. 9 is the same as ‘GND’ terminal in FIG. 8.
FIG. 10. illustrates the use of the circuit symbol from FIG. 9. in a circuit diagram. It shows connectivity between a signal source, said invention and load. In this figure a DC source ‘Vin’ is applied between ‘C (common)’ and ‘G (ground)’ terminal. A load resistance ‘RL’ is connected between ‘C (common)’ and ‘V (output)’ terminal. ‘C1 (capacitor)’, an optional component, helps in getting rid of any ripples in the output voltage. ‘L1’—inductor, ‘L2’—inductor and C2′—electrolytic capacitor are passive components connected between the output, PIN-1 (depicted by number 1 in FIG. 10), PIN-2 (depicted by number 2 in FIG. 10) and ground terminals of the integrated circuit variation. This arrangement is not limited to the one show in FIG. 10. The inductors and capacitors can be interchanged and connected in any order between the output, PIN-1, PIN-2 and ground terminals.
FIG. 11. applies the circuit symbol of said invention from FIG. 6. to an example application circuit wherein a small voltage source—a battery of 1.5V is connected to a LED through said invention. This circuit demonstrates that even a low voltage can make a LED glow if properly connected with the invention. The 1.5V battery is connected between ‘C (common)’ and ‘G (ground)’ and the LED is connected across ‘C (common)’ and ‘V (output)’ terminals of the invention. ‘C1’ is an optional ceramic disc capacitor to reduce output voltage ripples.
DETAILED DESCRIPTION OF INVENTION
The present invention uses a combination of an oscillator circuit and a clamper circuit to boost voltage of an electrical signal. Said clamper circuit can be constructed in many different variations that may differ in the number and type of electrical energy storage components—inductors and capacitors.
Said oscillator can be constructed using a transistor, logical inverter, operational amplifier, integrated circuit 555, or any other oscillator circuit, that generates an AC signal. Oscillator built with a switching transistor 2N2222 or with integrated circuit LMC555 can operate on voltage levels as low as 1V. When cascaded with an oscillator circuit, a clamper circuit shifts AC signal (generated by said oscillator) to a higher value voltage level. The value by which voltage level increases, depends on the number of stages implemented in said clamper circuit.
A clamper circuit is a network of diodes and capacitors electrically connected such as to achieve a DC voltage level shifting. Said invention makes use of Schottky diodes and electrolytic capacitors. Germanium diodes can also be used instead of Schottky diodes. Both types of diodes have low forward voltage drop compared to other diodes which help in better conservation of electrical energy. Some capacitors in said clamper circuit can be replaced by inductors to improve current response of the circuit. Any variation of clamper circuit is aimed at optimizing the output voltage and current per application requirements.
Present invention defines voltage gain which is determined by the ratio of output voltage level to input or source voltage level. FIG. 2. illustrates basic circuit diagram of the invention with six Schottky diodes and six capacitors. The approximate gain of this circuit is 3.3. This means, if a 1.5V battery is connected as input, the output voltage will be 4.95V.
Generally, 3-pin integrated circuit component can be manufactured as shown in FIG. 5. The source and/or biasing (if any, depending on the application) connects across the common and ground terminal and the load connects across the common and the output terminal of the component.
A variation of said invention wherein some segments in the clamper circuit are left open for users to decide between connecting capacitors or inductors. This is done to optimize the output voltage and current requirements of a load in any given application.
Providing this flexibility to the users by opening some terminals in the clamper circuit, a 6-pin integrated circuit is designed as shown in the FIG. 8. Just like the 3-pin integrated circuit, this component allows connection of source and/or biasing (if any, depending on the application) between the common and ground terminal. The load connects between the common and output terminal. Besides this, two additional terminals are defined for the 6-pin integrated circuit—Pin_1 and Pin_2. capacitors and/or inductors can be connected between output, Pin_1, Pin_2 and ground terminals.
Patent Application
20220376656
