LM3503SQ-16

Product Overview

Category: Integrated Circuits (ICs)

Use: Voltage Regulator

Characteristics: - High Efficiency - Low Dropout Voltage - Adjustable Output Voltage - Current Limit Protection - Thermal Shutdown Protection

Package: 16-WQFN (3x3)

Essence: The LM3503SQ-16 is a voltage regulator IC designed for various applications that require a stable and adjustable output voltage.

Packaging/Quantity: The LM3503SQ-16 is available in a 16-pin WQFN package. It is typically sold in reels of 2500 units.

Specifications

• Input Voltage Range: 2.7V to 5.5V
• Output Voltage Range: 1.2V to 3.6V
• Maximum Output Current: 500mA
• Dropout Voltage: 200mV at 100mA
• Quiescent Current: 50µA
• Operating Temperature Range: -40°C to +85°C

Pin Configuration

The LM3503SQ-16 has the following pin configuration:

```

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| | --| VOUT | --| GND | --| FB | --| EN | --| VIN | --| | --| | --| | --| | --| | --| | --| | --| | --| | --| | |___________| ```

Functional Features

1. High Efficiency: The LM3503SQ-16 utilizes advanced circuitry to achieve high efficiency, minimizing power loss and maximizing battery life.

2. Low Dropout Voltage: With a low dropout voltage of only 200mV at 100mA load, the LM3503SQ-16 can maintain a stable output voltage even when the input voltage is close to the desired output voltage.

3. Adjustable Output Voltage: The LM3503SQ-16 allows for easy adjustment of the output voltage within the specified range, providing flexibility for different application requirements.

4. Current Limit Protection: This IC incorporates current limit protection, preventing excessive current flow and protecting the circuit from damage.

5. Thermal Shutdown Protection: The LM3503SQ-16 features thermal shutdown protection, which automatically shuts down the device if the temperature exceeds the safe operating limits, ensuring reliable operation.

Advantages

• Compact package size
• Wide input voltage range
• Adjustable output voltage
• High efficiency
• Current limit and thermal shutdown protection

Disadvantages

• Limited maximum output current (500mA)
• Not suitable for high-power applications

Working Principles

The LM3503SQ-16 is a linear voltage regulator that uses a feedback mechanism to maintain a stable output voltage. It compares the output voltage with a reference voltage and adjusts the internal circuitry to regulate the output voltage at the desired level.

When the input voltage is within the specified range, the LM3503SQ-16 operates by controlling the pass transistor to adjust the voltage drop across it, thereby regulating the output voltage. It continuously monitors the output voltage and makes necessary adjustments to compensate for any changes in load conditions or input voltage variations.

Detailed Application Field Plans

The LM3503SQ-16 is commonly used in various battery-powered applications, such as:

1. Portable electronic devices
2. Wireless communication systems
3. Handheld medical devices
4. Industrial sensors
5. Automotive electronics

Alternative Models

Here are some alternative models that offer similar functionality:

1. LM317: Adjustable Linear Voltage Regulator
2. LT1763: Low Dropout Linear Regulator
3. TPS7A47: High-Voltage, Ultra-Low IQ Low-Dropout Linear Regulator
4. ADP3339: Ultralow Noise, High PSRR, Fast Transient Response LDO Regulator

These alternative models can be considered based on specific application requirements and design constraints.

In conclusion, the LM3503SQ-16 is a versatile voltage regulator IC that offers high efficiency, adjustable output voltage, and various protection features. Its compact size and wide input voltage range make it suitable for a wide range of battery-powered applications. However, its limited maximum output current may restrict its use in high-power applications.