This post explains for the regualtor.
The Part Number is 7133-1.
The function of this semiconductor is 30mA. Low Power LDO. ( Linear & low-dropout )
The package is TO-92, SOT-89 and SOT-25.
Manufacturer: Holtek
Preview images :
Description
This is 30mA Low Power LDO.
The 7133-1 is a set of three-terminal low power high voltage regulators implemented in CMOS
technology. They allow input voltages as high as 24V.
They are available with several fixed output voltages ranging from 3.0V to 5.0V. CMOS technology ensures low voltage drop and low quiescent current.
Features
1. Low power consumption
2. Low voltage drop
3. Low temperature coefficient
4. High input voltage (up to +18V)
5. Output voltage accuracy: tolerance ±2%
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Applications:
1. Battery-powered equipment
2. Communication equipment
3. Audio/Video equipment