MIC2941ABT

Introduction

The MIC2941ABT is a low dropout (LDO) linear voltage regulator, available in a fixed output voltage and current rating of 3.3V and 1.2 A. It is available in a DIP-8 package, allowing for easy mounting on circuit boards. It features superior noise suppression, high PSRR, low quiescent current, and low dropout voltage. The device is suitable for battery operated system, or stationary application requiring a low input voltage.

Application

The MIC2941ABT is a very efficient and cost-effective voltage regulator. It is commonly used in a variety of applications such as:

• Consumer electronics- MP3 players, digital cameras, cell phones, as well as other portable and stationary electronics
• Power supplies
• Battery-powered systems
• Generator or transceiver modules
• Medical equipment
• Automotive electronics and lighting

Features

The MIC2941ABT offers several features not found in more traditional voltage regulators:

• Low dropout voltage: only 0.5V (typical) under light load conditions
• High power supply rejection ratio (PSRR): 80dB at 10kHz
• Low quiescent current: 4 µA in Shutdown mode and 0.1 µA in normal operation
• Excellent EMI suppression due to internal noise filters
• High output accuracy: ±1%
• Operating temperature range of -40°C to 125°C
• Compliance with international safety standards
• Available in a DIP-8 package

Working Principle

The MIC2941ABT is an NPN-type linear voltage regulator, wherein an internal NPN transistor is employed as a voltage reference. An extremely low quiescent current is achieved by using an internal voltage reference, combined with a MOSFET pass transistor and minimal external components. This approach also helps to reduce EMI emissions, as any generated output frequency is well suppressed. The MOSFET pass transistor is then switched on and off to allow no-cost current limiting.

The MIC2941ABT offers two operation modes: normal operation and shutdown modes. In normal operation mode the device is continuously operating and regulated. During this mode, the device is constantly drawing current from the input source, allowing for continuous regulation. The quiescent current in this mode is extremely low and highly dependent on the type of load being supplied.

When the device enters the shutdown mode, its pass transistor is turned off and the device stops regulating. This eliminates current draw from the input source, reducing power consumption. However, the device is still able to meet the required output accuracy even when in shutdown mode.

Conclusion

The MIC2941ABT is a cost-effective and efficient linear voltage regulator, offering superior noise suppression, high PSRR, low quiescent current, and a low dropout voltage. It is commonly used in a variety of applications, such as consumer electronics, power supplies, medical equipment, automotive electronics and lighting. The device operates in two modes: normal operation, and shutdown mode and offers an operating temperature range of -40°C to 125°C, in addition to meeting all international safety standards.