AMS1117-3.3 Voltage Regulator Instructions for Use: From Principle to Application
07 March 2024
Ⅰ. Introduction to AMS1117-3.3
Ⅱ. Symbol, footprint and pin configuration of AMS1117-3.3
Ⅲ. What are the characteristics of AMS1117-3.3?
Ⅴ. Application cases of AMS1117-3.3
Ⅶ. Precautions for use of AMS1117-3.3
The AMS1117-3.3 is a high performance low dropout linear regulator which utilizes the bipolar process and has the advantages of good linearity, wide input voltage range, and small temperature drift. It is suitable for power management in a variety of electronic devices, especially for applications with stringent input voltage fluctuation requirements. This article will introduce you to the relevant information of AMS1117-3.3, and attach the pin diagram and schematic diagram.
The AMS1117 is a three-terminal voltage regulator featuring a voltage adjustment mechanism comprising a PNP-driven NPN transistor setup. It is available in fixed and adjustable versions with selectable output voltage ranges including: 1.2V, 1.5V, 1.8V, 2.5V, 2.85V, 3.0V, 3.3V, and 5.0V. The AMS1117-3.3 is a power supply regulator chip with an output voltage of 3.3V for high efficiency linear regulator applications. Its compact package design makes it easy to integrate into a variety of electronic boards, ideal for space-constrained application scenarios. It adopts advanced low dropout linear regulator technology to provide stable voltage output, which is widely used in a variety of regulated power supplies as well as industrial automation and medical devices.
Alternatives and equivalents:
• LM1117MPX-33NOPB
The AMS1117-3.3 features low dropout and efficient power conversion capabilities. It can maintain stable voltage output under different load conditions, which is crucial to prevent electronic products from being damaged by voltage fluctuations. In addition, AMS1117-3.3 also has overheating protection and overcurrent protection functions. When the chip temperature is too high or the current is too large, it can automatically protect the device from damage. This function not only improves the reliability of the chip itself, but also provides a solid guarantee for the safe operation of the entire electronic system.
The working principle of AMS1117-3.3 is shown in the figure:
AMS1117-3.3 consists of three main parts, namely reference voltage source, error amplifier and power transistor. The reference voltage source provides a stable reference voltage. The error amplifier compares the difference between the output voltage and the reference voltage and controls the output voltage by adjusting the conduction degree of the power transistor. When the input voltage or load current changes, the error amplifier automatically adjusts the conduction level of the power transistor to maintain a stable output voltage. When the output voltage is too high, the error amplifier will reduce the conduction degree of the power transistor, causing the output voltage to decrease; when the output voltage is too low, the error amplifier will increase the conduction degree of the power transistor, causing the output voltage to increase. In this way, AMS1117-3.3 realizes the voltage stabilization function of the input voltage.
1. Computer monitor
Computer monitor needs certain stable voltage and current to ensure the normal operation of the display, and AMS1117-3.3 can provide accurate 3.3V voltage for computer graphics cards, hard disk drives, etc., so that these devices can run properly.
2. Mahjong machine
Mahjong machine is a kind of interesting board game, its control circuit and scoring circuit need to use a large number of integrated circuits, and these circuits have very high requirements for voltage stability and noise immunity. Therefore, AMS1117-3.3 linear regulator can provide stable 3.3V voltage for these circuits to ensure the normal operation and stability of mahjong machine.
3. Instant noodle heater
In the instant noodle heater, in order to make sure the temperature is accurately controlled, we need to use heating elements and heating control chips. These chips have extremely high requirements on voltage and temperature, so they usually need to be powered by a high-precision voltage regulator. At this time, the AMS1117-3.3 linear voltage regulator can play a role in providing a precise 3.3V voltage to the heating control chip, thereby ensuring accurate temperature control.
4. Television
Modern TV sets integrate many electronic components inside, including image chips and control chips, etc. These components need stable and accurate voltage and current supply when working. Therefore, AMS1117-3.3 linear regulator plays an important role in it. Take the TV image chip as an example, its operating voltage is 3.3 V. If using a microcontroller as a voltage regulator circuit, not only the volume is huge, but also the cost will be relatively high. The AMS1117-3.3 linear regulator, on the other hand, is able to provide an accurate 3.3V voltage, while it is compact and easy to install, and can be mounted directly on the circuit board. This not only simplifies the circuit connection, but also greatly reduces the cost, so AMS1117-3.3 linear regulator has become an ideal choice for TV power supply design.
The following figure shows the circuit diagram of AMS1117-3.3:
From left to right are the input, ground and output terminals. In addition, C3 and C4 are output filter capacitors used to suppress self-excited oscillations. If these two capacitors are not connected, the output of the linear regulator will usually show an oscillating waveform. And C1 and C2 are input capacitors. Their main function is to convert the unidirectional pulsating voltage to DC voltage in the case of AC voltage rectifier input. In this diagram, since the input is already a +5V DC supply, their function is to prevent the voltage from inverting after a power failure. Therefore, the input capacitors are usually larger than the output capacitors.
When using AMS1117-3.3, we should pay attention to the following aspects:
1. Static protection: When handling and installing AMS1117-3.3, we should take appropriate static protection measures to avoid static electricity damage to the chip.
2. Packaging and welding: In practical applications, we need to select the appropriate packaging form for welding AMS1117-3.3 according to the specific application scenario. During the soldering process, we must follow the correct soldering methods and specifications to ensure that no damage is caused to the chip.
3. Input voltage range: The input voltage of AMS1117-3.3 should be within its specified operating voltage range, generally minimum 4.5 V and maximum 15 V. If the input voltage is out of this range, it may lead to chip damage or unstable performance.
4. Output current limit: The maximum output current of AMS1117-3.3 is 1 A. If the actual load current exceeds this limit, the chip may be damaged due to overheating. Therefore, it is important to ensure that the load current is kept within the allowable range during circuit design.
5. Power stability: The main function of AMS1117-3.3 is to provide a stable output voltage. However, in practice, we also need to take into account other factors, such as fluctuations in the input power supply and changes in the load, which may have an impact on the stability of the output voltage.
6. Heat dissipation: Although the AMS1117-3.3 is protected against overheating, heat dissipation is still a concern under high loads or high ambient temperatures. We should make sure that the chip is installed in an environment with good heat dissipation, and if necessary, we can add heat sinks to further improve the heat dissipation effect.
Frequently Asked Questions
1. What is the current of AMS1117 3.3 V?
The AMS1117 has a series of adjustable and fixed voltage regulators. This is a 3.3V Output Version of AMS1117. It provides up to 1A output current. It can also operate on 1V input to output differential.
2. What is AMS1117 3.3 V voltage regulator?
AMS1117-3.3 is a cost effective, low dropout (LDO) Voltage Regulator designed to provide current up to 1 amp. The maximum input voltage it can support is 15V.
3. What is the function of the AMS1117?
This is a popular voltage regulator used in electronic circuits to provide a stable and regulated 3.3 volts output. It is commonly used in various applications where a consistent and reliable power source is required to power low-voltage components or devices.
4. How does AMS1117 work?
The AMS1117 series develops a 1.25V reference voltage between the output and the adjust terminal. Placing a resistor between these two terminals causes a constant current to flow through R1 and down through R2 to set the overall output voltage. This current is normally the specified minimum load current of 10mA.
