The editor of Downcodes brings you a detailed explanation on achieving ±5V or ±12V output from a single power supply. This article will take an in-depth look at three commonly used power conversion methods: boost-buck converters, charge pump converters, and voltage divider converters, and recommend several commonly used power supply chips. Through the analysis of these methods and chips, I hope it can help you better understand the implementation principle of single-power bipolar output and choose an appropriate solution.
Achieving ±5V or ±12V output from a single power supply can be achieved by using a boost-buck converter, a voltage divider converter, a charge pump converter, etc. These power supplies or voltage regulator chips can provide positive and negative bipolar outputs through corresponding circuit designs, and can work directly from a single power supply such as 5V or 12V power input. Boost-buck converters are a very common choice that can generate bipolar output voltages from a single supply, and this type of converter has high efficiency and a wide output voltage range.
A boost-buck converter is a circuit topology commonly used in power supply design that converts an input voltage into a stable output voltage that is higher or lower than the input voltage. This type of converter is suitable for power systems that need to generate different voltage levels.
The working principle of the boost part is to use PWM (Pulse Width Modulation) signal to control the switching of the switching tube, store energy through the energy storage element (usually an inductor), and generate a voltage higher than the input voltage through the self-inductance of the inductor when the switching tube is turned off. voltage. This process realizes energy transfer through repeated switching actions, and finally outputs a stable high voltage.
The buck part controls the length of the switching time by adjusting the duty cycle of the PWM signal, thereby reducing the output voltage. This part of the circuit usually contains a synchronous rectifier to increase conversion efficiency. Voltage regulation is achieved through the output feedback loop to ensure the stability of the output voltage.
Charge pump converters are an inductor-less conversion method that is ideal for space-constrained or cost-sensitive applications. They achieve voltage conversion by alternately charging and discharging a capacitor.
The core of a charge pump converter lies in the charge and discharge cycle of the capacitor. During the charging phase, the capacitor absorbs energy from the input source. Then during the discharge phase, the capacitor releases the stored energy to the output, so that the required positive and negative voltages can be generated by controlling the charge and discharge of multiple capacitors.
Although the conversion efficiency of the charge pump converter is generally not as good as the boost-buck converter using an inductor, its structure is simple and the cost is low. For applications where the power is not very high, the charge pump is a very elegant solution.
Voltage divider converters are suitable for use when the output current demand is not high. They provide positive and negative output voltages through two independent regulators.
This part is usually implemented using a linear regulator or boost converter, which generates the required positive voltage output directly from the input supply. The design of the regulator must ensure the stability of the output voltage.
The negative voltage output is converted to a negative voltage by a buck converter or generated using a dedicated negative voltage linear regulator. In the design of a voltage divider converter, the balance of the positive and negative power supplies is very important, and it is necessary to ensure that the outputs of the two match by selecting appropriate components.
There are many application-specific integrated circuits (ICs) on the market that have the above functions and can be used to achieve ±5V or ±12V output from a single power supply.
The LT1054 is a widely used charge pump DC-DC converter IC that can generate a corresponding negative output voltage from a positive input voltage. The chip is widely used in portable devices that require small size and simplified circuitry.
The TPS65130 is a dual-output DC-DC converter produced by Texas Instruments. It can provide a boosted positive output voltage and a bucked negative output voltage from a single supply of 2.7V to 5.5V, making it ideal for applications such as OLED displays.
When implementing a single power supply output of ±5V or ±12V, designers need to consider the efficiency, cost, size of the circuit, and the stability of the power supply. Different application scenarios may have an important impact on the choice of power solution. The above converter types and specific power chips provide a variety of choices, and designers can choose the most suitable solution according to their specific needs.
1. What power supplies or voltage regulator chips can achieve bipolar (±5 or ±12V) output from a single power supply?
There are a variety of power supplies or voltage regulator chips on the market that can achieve bipolar output from a single power supply. A common solution is to use dual voltage regulator chips such as the LM337 and LM317. These chips can achieve positive and negative output from a single power supply through circuit design, and have good linearity and stability.
2. How to achieve ±5 or ±12V output from a single power supply?
To achieve ±5 or ±12V output from a single power supply, a voltage regulator chip and some external circuit components can be used to build a reliable power supply system. A common method is to use a positive voltage regulator chip and a negative voltage regulator chip and connect them to the appropriate circuit. By appropriately selecting the parameters of the voltage regulator chip and configuring external circuit components, the required output voltage of ±5 or ±12V can be obtained.
3. Which power supply or voltage regulator chip should be selected in the project to achieve ±5 or ±12V output from a single power supply?
There are several factors to consider when choosing a power supply or voltage regulator chip. First, you need to determine the desired output voltage range (±5V or ±12V). Secondly, you need to consider the required output current and power capabilities to ensure the chip can meet the needs of the project. Finally, you also need to consider the chip's performance indicators such as stability, linearity, and temperature coefficient to ensure that it can provide stable power output. Common choices include voltage regulator chips such as LM337 and LM317, but the specific applicability depends on the project requirements.
I hope that the explanation by the editor of Downcodes can help you solve the problem of single power supply bipolar output. If you have any questions, please leave a message in the comment area to discuss!