LD29300P2M33

LD29300P2M33 Application Field and Working Principle

LD29300P2M33 is a two-channel low dropout (LDOs) linear voltage regulator that s designed to operate from 3V to 5.5V input voltage. The device combines 2.5V and 3.3V output, low dropout voltage, internal current and thermal limit, and thermal shutdown protection in a small 3-pin SOT-23-5L package. This makes LD29300P2M33 suitable for a wide variety of applications such as portable electronic batteries, instrumentation, communications equipments and PC motherboards.

The operating principle of LD29300P2M33 is quite simple. The device has an internal reference voltage which is set by external resistors. This reference voltage is applied across an internal P-channel MOSFET which serves as a current source. The P-MOSFET is connected between the input voltage and the Collector of an NPN bipolar transistor. The Collector is connected to an output terminal while the base of the NPN transistor is connected to the Emitter. When the ratio of these two resistors is changed, the reference voltage will change, resulting in an adjustment to the output voltage.

Under normal operating conditions, the LD29300P2M33 acts as a voltage regulator and maintains a constant output voltage as the input voltage changes. It is able to supply up to 600mA of current to the load at a dropout voltage of less than 0.3V. In order to protect the device from current and thermal overloading, it has two limiting systems. The first is an internal current limiting which is set by an external resistor. The second is a thermal limiting system which will shut down the device if it gets too hot.

The advantages of the LD29300P2M33 linear voltage regulator are its low dropout voltage, input voltage flexibility, small package size and protection features. It is ideal for applications where space is limited and a lower dropout voltage is required. Its wide input voltage range also makes it suitable for a wide range of portable electronic applications where the battery supply voltage is gradually depleted. The protection features of the device ensure reliable operation even in harsh conditions.