Negative voltage generation power supply circuit
By using a negative voltage generation circuit composed of a PWM signal generation circuit and a transistor, combined with the Bluetooth main control chip BK3266, a negative voltage is generated to solve the problem of high cost of dedicated chips, thereby achieving low-cost and stable negative voltage power supply, improving the performance of the audio amplifier and the system safety.
Patent Information
- Application Number
- CN202520444461.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-13
- Publication Date
- 2026-02-10
- Estimated Expiration
- 2035-03-13
AI Technical Summary
In the existing technology, dedicated negative voltage generating chips are expensive, difficult to reduce costs effectively in mass production, and have a complex structure.
The system employs a PWM signal generation circuit, a negative voltage generation circuit, an operational amplifier circuit, and an AMP analog power amplifier circuit. It utilizes PNP and NPN transistors to generate negative voltage, and achieves negative voltage generation through the Bluetooth main control chip BK3266, thereby reducing costs and improving system stability.
Generating a negative voltage increases the output power of the audio amplifier, reduces the risk of high current caused by electron buildup, protects equipment safety, improves system stability and efficiency, and saves static power consumption.
Smart Images
Figure CN223899194U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power supply technology, specifically to a negative voltage generating power supply circuit. Background Technology
[0002] In traditional soundbar or Bluetooth speaker designs, situations sometimes require the use of negative voltage. This typically occurs when specific components in the circuit design require negative voltage power, such as certain audio amplifiers or operational amplifiers. To meet this need, there are generally two options: using a dedicated negative voltage generating chip, or employing a controlled negative voltage generation power supply circuit based on discrete components such as transistors.
[0003] However, chips that generate negative voltages typically offer high efficiency and small size, provide stable output, and often incorporate multiple protection functions such as overheat protection and short-circuit protection. However, these specialized chips are relatively expensive, especially during mass production, where cost becomes a more significant factor. Utility Model Content
[0004] This invention addresses the shortcomings and deficiencies of existing technologies by providing a low-cost and simple negative pressure generating power supply circuit.
[0005] To achieve the above objectives, the present invention provides a negative voltage generating power supply circuit, comprising a PWM signal generating circuit, a negative voltage generating circuit, an operational amplifier circuit, and an AMP analog power amplifier circuit; the signal output terminal of the PWM signal generating circuit is electrically connected to the negative voltage generating circuit, the input terminal of the operational amplifier circuit is electrically connected to the negative voltage generating circuit, and the output terminal of the operational amplifier circuit is electrically connected to the PWM signal generating circuit and the AMP analog power amplifier circuit.
[0006] Further, the negative voltage generating circuit includes a first transistor, a second transistor, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a first diode, and a second diode; the first resistor and the second resistor are connected in series, with one end electrically connected to the base of the first transistor and the other end electrically connected to the base of the second transistor; the signal output terminal of the PWM signal generating circuit is electrically connected to the common terminal of the first resistor and the second resistor; one end of the third resistor is electrically connected to a 5V power supply, and the other end is electrically connected to the emitter of the first transistor; the collector of the first transistor is electrically connected to the collector of the second transistor, and the emitter of the second transistor is grounded; the first capacitor, the first diode, and the second capacitor are connected in series, with one end electrically connected to the emitter of the second transistor and the other end electrically connected to the collector of the first transistor; one end of the second diode is electrically connected to the first diode, and the other end is electrically connected to the second capacitor; the common terminal of the first diode and the second capacitor is electrically connected to a 5V power supply.
[0007] Further; the operational amplifier circuit includes an operational amplifier, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, a thirteenth capacitor, and a fourteenth capacitor; the third capacitor and the fourth resistor are connected in series, one end of which is electrically connected to the output terminal of the operational amplifier, and the other end is connected to a differential analog signal; the fourth capacitor and the fifth resistor are connected in series, one end of which is electrically connected to the input terminal of the operational amplifier, and the other end is connected to a differential analog signal; the fifth capacitor and the sixth resistor are connected in series, one end of which is electrically connected to the non-inverting input terminal of the operational amplifier, and the other end is connected to a differential analog signal; the sixth capacitor and the seventh resistor are connected in series, one end of which is electrically connected to the inverting output terminal of the operational amplifier, and the other end is connected to a differential analog signal; the operational amplifier... The negative power supply terminal of the amplifier is electrically connected to the first diode. The seventh and eighth capacitors are connected in parallel, with one end connected to the negative power supply terminal of the operational amplifier and the other end grounded. The ninth capacitor and the eighth resistor are connected in parallel, with one end connected to the seventh resistor and the other end connected to the output terminal of the operational amplifier. One end of the tenth capacitor is connected to the AMP analog power amplifier circuit and the other end is connected to the output terminal of the operational amplifier. The ninth resistor and the eleventh capacitor are connected in parallel, with one end connected to the fourth resistor and the other end connected to the output terminal of the operational amplifier. The positive power supply terminal of the operational amplifier is connected to the third resistor. One end of the twelfth capacitor is connected to the output terminal of the operational amplifier and the other end is connected to the AMP analog power amplifier circuit. The thirteenth and fourteenth capacitors are connected in parallel, with one end grounded and the other end connected to the positive power supply terminal of the operational amplifier.
[0008] Furthermore, the first transistor is a PNP transistor, and the second transistor is an NPN transistor.
[0009] Furthermore, the PWM signal generation circuit includes a Bluetooth master control chip, the model of which is BK3266.
[0010] The beneficial effects of this utility model are:
[0011] This invention provides a negative voltage generation power supply circuit. By inputting a PWM signal into the negative voltage generation circuit, a negative voltage can be generated and output to the operational amplifier circuit. This allows the operational amplifier to output more energy when processing negative half-wave audio signals, thereby increasing the overall output power. This design not only effectively reduces costs but also avoids high current phenomena caused by electron accumulation, protecting test equipment and electronic components from damage and improving system stability. Furthermore, using negative voltage in the audio amplifier circuit not only improves efficiency but also saves unnecessary static power consumption. Compared to positive voltage, negative voltage offers better safety performance for people and electronic products. In summary, this application not only has a simple structure and low manufacturing cost but also performs excellently in improving system stability and safety. Attached Figure Description
[0012] Figure 1 This is a block diagram illustrating the working principle of a negative pressure generating power supply circuit according to this utility model.
[0013] Figure 2 This is a circuit diagram of the negative voltage generating circuit in a negative voltage generating power supply circuit according to the present invention.
[0014] Figure 3 This is a circuit diagram of the operational amplifier circuit in a negative voltage generating power supply circuit according to this utility model. Detailed Implementation
[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0016] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.
[0017] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.
[0018] This utility model proposes a negative pressure generating power supply circuit.
[0019] In the embodiments of this utility model, such as Figure 1-3 As shown, this negative voltage generating power supply circuit includes a PWM signal generating circuit, a negative voltage generating circuit, an operational amplifier circuit, and an AMP analog power amplifier circuit; the signal output terminal of the PWM signal generating circuit is electrically connected to the negative voltage generating circuit, the input terminal of the operational amplifier circuit is electrically connected to the negative voltage generating circuit, and the output terminal of the operational amplifier circuit is electrically connected to the PWM signal generating circuit and the AMP analog power amplifier circuit.
[0020] In this embodiment, the negative voltage generating circuit includes a first transistor, a second transistor, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a first diode, and a second diode. The first resistor and the second resistor are connected in series, with one end electrically connected to the base of the first transistor and the other end electrically connected to the base of the second transistor. The signal output terminal of the PWM signal generating circuit is electrically connected to the common terminal of the first resistor and the second resistor. One end of the third resistor is electrically connected to a 5V power supply, and the other end is electrically connected to the emitter of the first transistor. The collector of the first transistor is electrically connected to the collector of the second transistor, and the emitter of the second transistor is grounded. The first capacitor, the first diode, and the second capacitor are connected in series, with one end electrically connected to the emitter of the second transistor and the other end electrically connected to the collector of the first transistor. One end of the second diode is electrically connected to the first diode, and the other end is electrically connected to the second capacitor. The common terminal of the first diode and the second capacitor is electrically connected to a 5V power supply.
[0021] In this embodiment, the operational amplifier circuit includes an operational amplifier, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, a thirteenth capacitor, and a fourteenth capacitor; the third capacitor and the fourth resistor are connected in series, one end of which is electrically connected to the output terminal of the operational amplifier, and the other end is connected to a differential analog signal; the fourth capacitor and the fifth resistor are connected in series, one end of which is electrically connected to the input terminal of the operational amplifier, and the other end is connected to a differential analog signal; the fifth capacitor and the sixth resistor are connected in series, one end of which is electrically connected to the non-inverting input terminal of the operational amplifier, and the other end is connected to a differential analog signal; the sixth capacitor and the seventh resistor are connected in series, one end of which is electrically connected to the inverting output terminal of the operational amplifier, and the other end is connected to a differential analog signal; the operational amplifier... The negative power supply terminal of the amplifier is electrically connected to the first diode. The seventh and eighth capacitors are connected in parallel, with one end connected to the negative power supply terminal of the operational amplifier and the other end grounded. The ninth capacitor and the eighth resistor are connected in parallel, with one end connected to the seventh resistor and the other end connected to the output terminal of the operational amplifier. One end of the tenth capacitor is connected to the AMP analog power amplifier circuit and the other end is connected to the output terminal of the operational amplifier. The ninth resistor and the eleventh capacitor are connected in parallel, with one end connected to the fourth resistor and the other end connected to the output terminal of the operational amplifier. The positive power supply terminal of the operational amplifier is electrically connected to the third resistor. One end of the twelfth capacitor is connected to the output terminal of the operational amplifier and the other end is connected to the AMP analog power amplifier circuit. The thirteenth and fourteenth capacitors are connected in parallel, with one end grounded and the other end connected to the positive power supply terminal of the operational amplifier.
[0022] In this embodiment, the first transistor is a PNP transistor and the second transistor is an NPN transistor.
[0023] In this embodiment, the PWM signal generation circuit includes a Bluetooth master control chip, the model of which is BK3266.
[0024] Specifically, this application provides a -5V power supply to the operational amplifier circuit through a negative voltage generation circuit, which can effectively increase the output power of the operational amplifier circuit.
[0025] The specific tasks are as follows:
[0026] When the PWM signal generation circuit inputs a low-level signal to the negative voltage generation circuit through PWM_GPIO6, the first transistor Q5 (PNP type) turns on, while the second transistor Q4 (NPN type) turns off. At this time, the +5V power supply (POWER_5V) flows through the first transistor Q5 to charge the first capacitor EC1. The charging path is: from POWER_5V through the third resistor 3R5, the first transistor Q5, the first capacitor EC1, the second diode D2, and finally back to GND. After charging is complete, the polarity of the first capacitor EC1 is left positive and right negative.
[0027] When the PWM_GPIO6 input is high, the first transistor Q5 is cut off, and the second transistor Q4 is turned on, causing the first capacitor EC1 to begin discharging. The discharge path is: from the first capacitor EC1 through the second transistor Q4, the second capacitor EC2, the first diode D38, and finally to the negative terminal of the second capacitor EC2. This process actually charges the second capacitor EC2. After charging is complete, the polarity of the first capacitor EC1 changes to positive at the bottom and negative at the top. If the emitter input voltage of the first transistor Q5 is +5V, then this circuit can output a -5V (POWER_-5V) supply voltage.
[0028] The aforementioned negative voltage generation circuit generates a POWER_-5V voltage, which is then used to power the operational amplifier circuit. When the operational amplifier circuit receives an external differential analog signal, the AMP_L_OUT and AMP_R_OUT ports can output a maximum of approximately +5V and -5V, respectively, corresponding to the positive and negative half-cycle signals. This not only improves the overall performance of the power amplifier but also enhances the system's stability and efficiency.
[0029] This design utilizes negative voltage to extend the operating range of the audio amplifier, thereby improving overall performance while reducing cost and quiescent power consumption. Furthermore, using negative voltage avoids excessive current caused by electron buildup, protecting test equipment and electronic components.
[0030] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.
Claims
1. A negative voltage generating power supply circuit, characterized in that, It includes a PWM signal generation circuit, a negative voltage generation circuit, an operational amplifier circuit, and an AMP analog power amplifier circuit; the signal output terminal of the PWM signal generation circuit is electrically connected to the negative voltage generation circuit, the input terminal of the operational amplifier circuit is electrically connected to the negative voltage generation circuit, and the output terminal of the operational amplifier circuit is electrically connected to the PWM signal generation circuit and the AMP analog power amplifier circuit.
2. The negative voltage generating power supply circuit as described in claim 1, characterized in that, The negative voltage generating circuit includes a first transistor, a second transistor, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a first diode, and a second diode. The first resistor and the second resistor are connected in series, with one end electrically connected to the base of the first transistor and the other end electrically connected to the base of the second transistor. The signal output terminal of the PWM signal generating circuit is electrically connected to the common terminal of the first resistor and the second resistor. One end of the third resistor is electrically connected to a 5V power supply, and the other end is electrically connected to the emitter of the first transistor. The collector of the first transistor is electrically connected to the collector of the second transistor, and the emitter of the second transistor is grounded. The first capacitor, the first diode, and the second capacitor are connected in series, with one end electrically connected to the emitter of the second transistor and the other end electrically connected to the collector of the first transistor. One end of the second diode is electrically connected to the first diode, and the other end is electrically connected to the second capacitor. The common terminal of the first diode and the second capacitor is electrically connected to a 5V power supply.
3. The negative voltage generating power supply circuit as described in claim 2, characterized in that, The operational amplifier circuit includes an operational amplifier, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, a thirteenth capacitor, and a fourteenth capacitor. The third capacitor and the fourth resistor are connected in series, one end of which is electrically connected to the output terminal of the operational amplifier, and the other end is connected to a differential analog signal. The fourth capacitor and the fifth resistor are connected in series, one end of which is electrically connected to the input terminal of the operational amplifier, and the other end is connected to a differential analog signal. The fifth capacitor and the sixth resistor are connected in series, one end of which is electrically connected to the non-inverting input terminal of the operational amplifier, and the other end is connected to a differential analog signal. The sixth capacitor and the seventh resistor are connected in series, one end of which is electrically connected to the inverting output terminal of the operational amplifier, and the other end is connected to a differential analog signal. The operational amplifier... The negative power supply terminal of the amplifier is electrically connected to the first diode. The seventh and eighth capacitors are connected in parallel, with one end connected to the negative power supply terminal of the operational amplifier and the other end grounded. The ninth capacitor and the eighth resistor are connected in parallel, with one end connected to the seventh resistor and the other end connected to the output terminal of the operational amplifier. One end of the tenth capacitor is connected to the AMP analog power amplifier circuit and the other end is connected to the output terminal of the operational amplifier. The ninth resistor and the eleventh capacitor are connected in parallel, with one end connected to the fourth resistor and the other end connected to the output terminal of the operational amplifier. The positive power supply terminal of the operational amplifier is connected to the third resistor. One end of the twelfth capacitor is connected to the output terminal of the operational amplifier and the other end is connected to the AMP analog power amplifier circuit. The thirteenth and fourteenth capacitors are connected in parallel, with one end grounded and the other end connected to the positive power supply terminal of the operational amplifier.
4. The negative voltage generating power supply circuit as described in claim 2, characterized in that, The first transistor is a PNP transistor, and the second transistor is an NPN transistor.
5. The negative voltage generating power supply circuit as described in claim 1, characterized in that, The PWM signal generation circuit includes a Bluetooth master control chip, the model of which is BK3266.