MAX666CPA+

MAX666CPA+ is a low dropout (LDO) linear 3-terminal voltage regulator designed for miniaturized portable applications. It is designed to provide clean output voltage with low noise over a wide range of input and output voltages. The device operates from input voltages up to 5.5V and is capable of supplying up to 1A of continuous current. The device features low quiescent current, 0.4 µA typical, and low dropout voltage of 20 mV at 1A. It is also designed with an output voltage range of 0.8V to 5.0V and an adjustable output voltage range of 1.2V to 5.0V.

MAX666CPA+ combines the flexibility of adjustable voltage regulation with a CMOS-based solution that has the simplicity of a three terminal voltage regulator. The low dropout voltage, fast transient response and low quiescent current make it an ideal choice for a wide range of portable applications including personal digital assistants (PDAs), cellular phones, portable medical instruments, and laptop computers. The MAX666CPA+ also features a 2kHz fixed frequency internal oscillator allowing for quick start-up and stability at light loads.

The MAX666CPA+ application field and working principal are mainly of the following points:

• Input voltage: Depending on the actual product, the MAX666CPA+ has an input voltage of 2.7V, 3V, 3.3V, and 5V.
• Output voltage range: The MAX666CPA+ output voltage range is 0.8V to 5.0V, while the adjustable output voltage range is 1.2V to 5.0V.
• Dropout Voltage: The dropout voltage of the device is typically 20mV at 1A.
• Quiescent Current: The quiescent current of the device is 0.4uA.
• Maximum Output Current: The MAX666CPA+ can deliver a continuous output current of up to 1A.
• Transient Response: The device has fast transient response and low output voltage noise.
• Oscillator Frequency: The MAX666CPA+ features a 2kHz fixed frequency internal oscillator allowing for quick start-up and stability at light loads.
• Protection Features: The device is designed with over-temperature, current limit, and over-voltage protection features.

The MAX666CPA+ operation starts with the application of input voltage. An internal oscillator generates control signals to turn the error amplifier and pass transistor on and off. This oscillator also limits the current flowing through the pass transistor to limited values. The error amplifier monitors the output voltage via an internal feedback loop and generates an output voltage according to the output voltage setting. The feedback voltage is then compared to the reference voltage and a correction is made to ensure that the output voltage stays close to the set point. To prevent over-current and over-voltage conditions, the device includes an internal current limit and over-voltage protection.

The MAX666CPA+ is an ideal choice for a wide range of portable applications such as PDAs, cell phones, laptop computers, and portable medical instruments. With its low dropping voltage and quiescent current, small size, and wide operating temperature range, the MAX666CPA+ is a perfect fit for space-constrained applications. Additionally, its fast transient response and low output voltage noise make it an excellent choice for high-performance and low-power applications.