Overview
The PT78ST105H from Texas Instruments is a 1.5 Amp Positive Step-Down Integrated Switching Regulator (ISR). This component is part of the PT78ST100 series, known for its high efficiency, small footprint, and robust protection features. It is designed to provide a stable output voltage from a wide range of input voltages, making it versatile for various applications. The PT78ST105H is specifically configured to output 5.0 volts, which is laser-trimmed to industry standard voltages.
Key Specifications
| Parameter | Min | Max | Units | |
|---|---|---|---|---|
| Output Current (Io) | 0.1 | - | 1.5 | A |
| Short Circuit Current (Isc) | - | - | 3.5 | A |
| Input Voltage Range (Vin) | 9 | - | 38 | V |
| Output Voltage Tolerance (∆Vo) | - | ±1.0 | ±2.0 | %Vo |
| Line Regulation (Regline) | - | ±0.2 | ±0.4 | %Vo |
| Load Regulation (Regload) | - | ±0.1 | ±0.2 | %Vo |
| Output Voltage Ripple/Noise (Vn) | - | 65 | - | mVpp |
| Transient Response (ttr) | - | 100 | - | µSec |
| Efficiency (η) | - | 85 | - | % |
| Switching Frequency (ƒo) | 600 | 650 | 700 | kHz |
| Operating Temperature Range (Ta) | -40 | - | 80 | °C |
| Storage Temperature (Ts) | -40 | - | 125 | °C |
Key Features
- High Efficiency: The PT78ST105H offers high efficiency greater than 85%, making it suitable for applications where power consumption is a concern.
- Self-Contained Inductor: The regulator includes an internal inductor, reducing the need for external components and saving board space.
- Internal Protection: It features internal short-circuit and over-temperature protection, enhancing reliability and safety.
- Fast Transient Response: The regulator has a fast transient response, ensuring stable output voltage under varying load conditions.
- Wide Input Range: The component can operate over a wide input voltage range from 9V to 38V, making it versatile for different power sources.
- Small Footprint: The PT78ST105H is available in a compact package, ideal for space-constrained designs.
Applications
The PT78ST105H is suitable for a wide range of applications, including:
- Industrial Control Systems: Where stable and efficient power supply is crucial.
- Medical Devices: Requiring high reliability and precision in power regulation.
- Automotive Systems: Where the component must withstand a wide range of input voltages and temperatures.
- Consumer Electronics: Such as set-top boxes, routers, and other devices needing efficient power management.
- Telecommunication Equipment: Where high efficiency and reliability are essential.
Q & A
- What is the output voltage of the PT78ST105H?
The PT78ST105H is configured to output 5.0 volts. - What is the maximum output current of the PT78ST105H?
The maximum output current is 1.5 amps. - What is the input voltage range for the PT78ST105H?
The input voltage range is from 9V to 38V. - Does the PT78ST105H have internal protection features?
Yes, it includes internal short-circuit and over-temperature protection. - What is the switching frequency of the PT78ST105H?
The switching frequency ranges from 600 kHz to 700 kHz. - What is the efficiency of the PT78ST105H?
The efficiency is greater than 85%. - What type of capacitor is required for proper operation?
A 100µF electrolytic or tantalum output capacitor is required. - What is the operating temperature range of the PT78ST105H?
The operating temperature range is from -40°C to +80°C. - Is the PT78ST105H suitable for high-temperature environments?
Yes, it can operate up to 80°C and store up to 125°C. - What are the mechanical robustness features of the PT78ST105H?
It withstands mechanical shock and vibration as per Mil-STD-883D standards.
