The SPX1121N-5.0 is a 100mA low dropout (LDO) linear regulator manufactured by Sipex Corporation (later acquired by Exar Corporation). It provides a fixed 5.0V output voltage with a low dropout voltage, making it suitable for applications requiring a stable and regulated power supply.

Applications

• Battery-powered devices
• Portable electronics
• Post-regulation for switching power supplies
• Microprocessor power supplies
• Handheld instruments

Features

• Fixed Output Voltage: Provides a precise 5.0V output.
• Low Dropout Voltage: Typically 200mV at 100mA, allowing operation with a small difference between input and output voltage.
• Low Quiescent Current: Typically 50µA, minimizing power consumption in standby mode.
• Short-Circuit Protection: Protects the regulator and the load from damage in case of a short circuit.
• Over-Temperature Protection: Shuts down the regulator if the junction temperature exceeds a safe limit.
• Stable with Ceramic Capacitors: Designed to work with low-ESR ceramic output capacitors for improved stability.
• Small Package: Available in compact packages like SOT-223, suitable for space-constrained applications.

Benefits

• Stable Power Supply: Provides a stable and regulated 5.0V output, ensuring proper operation of connected devices.
• Extended Battery Life: Low quiescent current minimizes power consumption and extends battery life in portable devices.
• Enhanced Reliability: Short-circuit and over-temperature protection features prevent damage and improve system reliability.
• Simplified Design: Stable with ceramic capacitors, simplifying circuit design and reducing component count.
• Compact Size: Small package options allow for use in space-constrained applications.

Additional Details

The SPX1121N-5.0 requires a minimum input voltage slightly above 5.0V to operate correctly. It can handle input voltages up to 16V. The output current is limited to 100mA. The regulator's thermal resistance is relatively low, allowing it to dissipate heat effectively. This LDO regulator is a versatile and reliable solution for providing a stable 5.0V power supply in a wide range of applications, especially those requiring low power consumption and compact size.