AL5809-25P1-7 Integrated Circuits (ICs)

AL5809-25P1-7 is a chip that belongs to the PMIC - LED Drivers category. It is typically used to drive LEDs and is also suitable for powering microprocessors, DSPs and FPGAs.

AL5809-25P1-7 is a Constant Current source with a wide regulation range, from 0.2V to 10V, and a maximum output current of 25mA. The chip can be configured to regulate the LED current through an external current-setting resistor. The AL5809-25P1-7 also offers high efficiency, low output ripple, and built-in protections for output over-current and over-temperature.

The AL5809-25P1-7 has an extensive application field. It supports a wide range of LED drivers, including constant current drivers for external LED strings, automotive LED drivers, network LED drivers, indoor LED drivers, and outdoor LED drivers.

It is also used in industrial settings and can power microprocessors, digital signal processors, field-programmable gate arrays, and small microcontrollers, making it suitable for a variety of applications.

To understand better the AL5809-25P1-7, we need to take a look at its working principle. Firstly, the current at the output is sensed and mirrored onto the negative input of an operational amplifier. This current flows through an external resistor, R SET, which sets the voltage at the negative input and thus determines the output current.

As the current increases and the voltage at negative input of the operational amplifier rises, the amplifier compensates by reducing the output current . Meanwhile, the difference between the output voltage and the internal reference voltage, VREF, is sensed by an internal voltage divider, composed of external resistors R1 and R2.

This voltage difference enters the positive input of the operational amplifier, and is compared to the voltage at the negative input (VREG), derived from the sense resistor. If the positiove input voltage is higher, the amplifier compensates by reducing the output current, thus maintaining a certain output voltage (VOUT)

In addition, to protect against over-current conditions, an over-current detector (OCD) is also included on the chip. This device monitors the voltage across the sense resistor and its internal threshold voltage. When the voltage across the sense resistors exceeds the threshold, the OCD shuts down the output, protecting the device from the over-current condition.

Lastly, an over-temperature detector (OTD) senses the temperature of the device and shuts down the output when the temperature reaches a certain limit, protecting the chip from thermal stress.

The AL5809-25P1-7 has many features that make it an ideal choice for LED drivers and other industrial applications. It is designed for high efficiency, has a wide regulation range, low output ripple, and built-in protections for both over-current and over-temperature.