The AMS1117 is widely used LDO regulators because of its simple design, stable output, and ability to provide up to 1A of output current. Its availability in both fixed and adjustable voltage versions also makes it suitable for a wide range of power regulation applications. This article will discuss the AMS1117 LDO regulator, including its pinout, specifications, features, working principle, applications, and more.

Catalog

AMS1117 LDO Regulator Basic

The AMS1117 is a 1A low dropout (LDO) linear voltage regulator designed to provide a stable output voltage for electronic circuits. It can supply up to 1A output current and operates with a small input-to-output voltage difference, making it suitable for systems where power efficiency and stable regulation are important. The device typically has a dropout voltage of about 1.3V, which becomes lower when the load current decreases.

The regulator includes on-chip trimming that keeps the reference voltage accuracy within about 1.5%, helping maintain stable output performance. It also features current limiting protection, which helps reduce stress on the regulator and the power source during overload conditions. The AMS1117 series is pin-compatible with many three-terminal regulators and is available in packages such as SOT-223, TO-252 (DPAK), and SOIC-8.

If you are interested in purchasing the AMS1117 1A LDO Regulator, feel free to contact us for pricing and availability.

AMS1117 LDO Regulator CAD Models

AMS1117 LDO Regulator Pinout

AMS1117 LDO Regulator Variants

Alternatives & Equivalent Model

• LM1117

• LM1117MPX-3.3

• LD1117

• NCP1117

• AZ1117

• AP1117

• TLV1117

• RT9167

• MCP1702

• LP2985

• MIC5205

AMS1117 LDO Regulator Specifications

AMS1117 LDO Regulator Features

Three-Terminal Adjustable or Fixed Output Voltage

The AMS1117 regulator is available in both fixed and adjustable output voltage versions. Fixed versions commonly include 1.5V, 1.8V, 2.5V, 2.85V, 3.3V, and 5V, while the adjustable version allows users to set the desired output voltage using external resistors. This flexibility makes the regulator suitable for many electronic circuits and power supply designs.

Up to 1A Output Current

The device can deliver up to 1A of output current, which is enough to power many embedded systems, microcontroller boards, and communication modules. This capability allows the regulator to support moderate power loads while maintaining stable voltage regulation.

Low Dropout Voltage

The AMS1117 operates with a low dropout voltage of about 1V to 1.3V, depending on load current. This means the input voltage only needs to be slightly higher than the output voltage for the regulator to work properly, making it useful in low-voltage power supply applications.

Good Line Regulation

It provides line regulation of about 0.2% maximum, which means the output voltage remains stable even when the input voltage changes. This helps maintain consistent performance in circuits that experience input voltage variations.

Stable Load Regulation

The AMS1117 also offers load regulation of around 0.4% maximum, ensuring the output voltage remains stable when the connected load current changes. This is important for circuits that have varying power consumption.

Multiple Package Options

The regulator is available in several package types including SOT-223, TO-252 (DPAK), and SO-8. These packaging options make it easy to use the device in different PCB designs, from compact consumer electronics to larger power regulation circuits.

AMS1117 LDO Regulator Working in Circuit

In this circuit, the AMS1117 regulator converts the input voltage (VIN) into a stable adjustable output voltage (VOUT). The resistors R1 and R2 form a voltage divider connected to the ADJ pin, which sets the final output voltage. By selecting the proper values of R1 and R2, the output voltage can be adjusted according to the formula shown in the diagram.

The COUT capacitor (22µF) helps stabilize the output and reduces voltage ripple. The CADJ capacitor (10µF) improves noise performance and increases ripple rejection of the regulator. The D1 diode protects the regulator when the input power suddenly drops while the output capacitor still holds charge, preventing reverse current from flowing back into the device.

AMS1117 LDO Regulator Applications

Microcontroller Power Supply

The AMS1117 is commonly used to provide a stable voltage for microcontrollers such as Arduino, ESP modules, and other development boards. It regulates a higher input voltage (like 5V or 12V) down to lower levels such as 3.3V, which many microcontrollers require for proper operation.

Embedded Systems

In embedded electronic systems, the AMS1117 helps supply a clean and steady voltage to processors, sensors, and communication modules. Its stable output ensures reliable system performance in devices like smart controllers and automation equipment.

Communication Devices

The regulator is often used in Wi-Fi modules, RF circuits, and communication equipment that need a stable low-voltage power source. It helps maintain consistent voltage levels to prevent signal instability.

Consumer Electronics

AMS1117 regulators are widely used in set-top boxes, media players, routers, and small electronic gadgets. They provide simple and reliable voltage regulation for internal circuit boards.

Battery-Powered Devices

The device can regulate voltage from batteries and provide a stable output for portable electronics. Its low dropout feature helps maintain regulation even when the battery voltage starts to drop.

Power Supply Modules

Many DC-DC power modules and adapter boards include the AMS1117 to step down voltage and supply regulated power to other circuits. This makes it useful in prototype boards and compact power supply designs.

AMS1117 Safely Operation

To operate the AMS1117 LDO regulator safely, the input voltage must stay within the recommended limit, typically below 15V. The input voltage should always be higher than the desired output voltage by at least the dropout voltage, usually about 1V to 1.3V, so the regulator can maintain proper regulation.

Proper heat management is important during operation. When the regulator drops voltage while supplying current, it dissipates power as heat. Using a PCB copper area or heat-dissipating package such as SOT-223 or TO-252 helps reduce temperature rise and prevents overheating.

Stable operation also requires input and output capacitors. A capacitor on the output (commonly around 10µF to 22µF) helps keep the output voltage stable and reduces noise. Following these practices ensures reliable performance and protects the regulator from damage.

Comparison: AMS1117 vs LD1117