SG3525AN Controller: Specifications, Application Circuit and Other Details
19 February 2024
Ⅲ. Application circuit of SG3525AN
Ⅳ. How to evaluate the efficiency of SG3525AN controller?
Ⅴ. Recommended operating conditions for SG3525AN
Ⅵ. What are the advantages and disadvantages of SG3525AN?
The S63525AN is a switching controller produced by STMicroelectronics. It plays an important role in supporting high-efficiency switching power supply applications, especially high-current power devices, mainly used in electric motors, LED light controls, and ultrasonic cleaning machines. This article will introduce the SG3525AN in detail to help you better apply this controller.
SG3525AN is a pulse width modulator IC designed to provide excellent performance and reduce the number of external parts when designing various types of switching power supplies. Its input voltage range is 8V to 35V and its operating temperature range is 0°C to 70°C. The on-chip 5.1V reference is trimmed by ±1 percent, and the error amplifier's input common-mode range includes the trimmed reference voltage, eliminating the need for external resistors. Only a single resistor is required between the CT and discharge terminals, providing a wide dead time adjustment range. Additionally, the device features built-in soft-start circuitry requiring only an external timing capacitor. The shutdown terminal not only controls the soft-start circuit and output stage, but also provides instantaneous shutdown via a PWM latch with pulsed shutdown capability, as well as the ability to implement a soft-start cycle when a longer shutdown command is received.
Alternatives and equivalents:
• SG2525AN
• SG3525AP
• SG3525AN adopts through-hole mounting.
• The manufacturer of SG3525AN is STMicroelectronics.
• Its duty cycle is 49 percent.
• Its switching frequency is 100Hz to 400kHz.
• It dissipates 1 W of power and has a quiescent current of 1 mA.
• It has a rise time of 100 ns and a fall time of 50 ns.
• SG3525AN belongs to the category of switching controllers.
• The SG3525AN comes with 16 pins, utilizing a PDIP-16 package and tube packaging.
• This voltage mode driver has a minimum operating temperature of 0°C and a maximum operating temperature of 70°C.
• The length of SG3525AN is 20 mm, the width is 7.1 mm, and the height is 5.1 mm.
• The device operates with a minimum supply voltage of 4.5 V and a maximum supply voltage of 35 V.
The efficiency of the SG3525AN controller depends on several factors, including current, input voltage, output voltage, and switching frequency. In practical applications, its efficiency can reach more than 90 percent with high energy conversion efficiency. However, the efficiency of the SG3525AN controller can be affected by factors such as the power supply circuit design and manufacturing process. In order to improve the efficiency of the controller, we need to carry out a reasonable circuit design, reduce losses, optimize the switching frequency and so on. In addition, we also need to pay attention to the heat dissipation design of the controller to ensure that the controller operates at normal operating temperature, thereby improving its working efficiency.
To evaluate the efficiency of the SG3525AN controller, we can follow the steps below. First, we calculate the input power by measuring the input voltage and current using a multimeter or power analyzer. Next, we calculate the output power by also measuring the output voltage and current. After that, we calculate the efficiency using the following formula: Efficiency = Output Power / Input Power × 100 Percent. We substitute the measured output power and input power into this formula to get the efficiency value of the controller. Finally, based on this efficiency value, we can analyze the performance of the SG3525AN controller. If the efficiency value is low, we may need to optimize or improve the controller to enhance its efficiency.
Note: The range over which the device is functional and the parameter limits are guaranteed.
1. Advantages of SG3525AN
• Flexibility: The SG3525AN controller provides a wealth of regulation functions, such as frequency control and duty cycle control, to meet the needs of different applications.
• Stability: By using suitable external components such as resistors, capacitors and diodes, the SG3525AN enables stable control of output voltage and current.
• Ease of integration: The SG3525AN controller is a controller with a standardized interface and pin arrangement. Its pinout follows industry standards for easy integration with other circuits, thus facilitating system design and maintenance.
• High reliability: The SG3525AN controller utilizes high-quality electronic components and a rigorous manufacturing process, resulting in high reliability and stability. This ensures sustained durability and steadfastness during extended operation, thereby guaranteeing the safety and stability of the system.
2. Disadvantages of SG3525AN
• Many peripheral components: In order to realize a specific function, the SG3525AN usually needs to work with several external components. These external components include diodes, inductors, capacitors, resistors, transistors, and so on. Due to the increased number of components, the layout of the board becomes more complex.
• Lower operating frequency: The operating frequency of this controller is generally in the range of tens of kHz to hundreds of kHz. Compared to some high-frequency PWM controllers, the SG3525AN has a lower power density and is therefore more energy efficient.
• Interference issues: The SG3525AN controller may generate electromagnetic interference during operation. This may affect the normal operation of the surrounding circuits, or even cause the entire system performance to degrade or become unstable. This EMI usually originates from high-speed switching actions and current variations within the controller, which generate transient electromagnetic fields in the surrounding space that can interfere with other sensitive circuits. In order to ensure that the SG3525AN controller can operate stably in complex electromagnetic environments, we need to design for electromagnetic compatibility.
The protection function of SG3525AN is one of the important features built into the power chip. It uses a specialized protection circuit to ensure system reliability and stability. On the one hand, the over-temperature protection function of SG3525AN can promptly detect abnormal rises in chip temperature and prevent the chip from overheating by automatically reducing the operating frequency or turning off the output. On the other hand, it also has a short-circuit protection function that can stop the output immediately when the output is short-circuited to avoid damage to the system and power supply. In short, the protection function of SG3525AN effectively protects the stable operation of the system and provides additional security.
In addition, SG3525AN also has over-voltage protection and under-voltage protection functions. When the input voltage exceeds the maximum operating voltage of the chip design, the overvoltage protection circuit of SG3525AN will automatically disconnect the power supply to avoid damage to the chip and system due to excessive voltage. When the input voltage is too low, the low-voltage protection circuit will automatically turn off the output to ensure the normal operation of the system. These protection functions enable SG3525AN to adapt to protection needs under different operating conditions and provide a reliable protection mechanism.
In addition to the built-in protection functions, users can also enhance the protection capabilities of the SG3525AN through external circuits. For example, we can use an overcurrent protection circuit to monitor the output current. Once the output current exceeds the set threshold, the protection circuit automatically cuts off the output to prevent system and power supply overload. In addition, we can also add overvoltage protection circuits, overload protection circuits, etc. to further protect the safety of the system. All in all, the SG3525AN not only has built-in protection functions, but can also be enhanced with external circuits to provide comprehensive protection measures to ensure system reliability and safety.
Frequently Asked Questions
1. What is SG3525 used for?
SG3525 is a pulse-width modulator IC. This IC is used to design all types of SMPS (Switched Mode Power Supply) and PWM signals for power electronics projects. It has improved performance and lower external parts and is a 16-pin IC.
2. What are the advantages of using SG3525AN?
Some advantages of SG3525AN include its versatility, high efficiency, adjustable frequency, and ease of integration into various power supply designs.
3. What is the purpose of SG3525AN?
The SG3525AN is designed to regulate the output voltage of power supplies or inverters by controlling the duty cycle of the switching transistors.
4. What is the maximum frequency of SG3525?
The range of values usable (as specified by the manufacturers of SG3525) is 0Ω to 500Ω. RT must be within the range 2kΩ to 150kΩ. CT must be within the range 1nF (code 102) to 0.2µF (code 224). The oscillator frequency must be within the range 100Hz to 400kHz.
