Overview
The L4971 is a step-down monolithic power switching regulator produced by STMicroelectronics. It delivers up to 1.5A of current at output voltages ranging from 3.3V to 50V, which can be selected using a simple external divider. The device is realized in BCD mixed technology and utilizes an internal power D-MOS transistor to achieve high efficiency and high switching speeds. The L4971 supports a wide input voltage range of 8V to 55V and features adjustable switching frequencies up to 300kHz.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Output Current | Up to 1.5A | A |
| Output Voltage Range | 3.3V to 50V | V |
| Input Voltage Range | 8V to 55V | V |
| Switching Frequency | Up to 300kHz | kHz |
| Internal Reference Voltage | 3.3V (±1%) | V |
| Package Types | DIP-8, SO-16W | |
| Operating Temperature Range | -40°C to 150°C | °C |
Key Features
- Pulse-by-pulse current limiting and hiccup mode for short circuit protection
- Voltage feedforward regulation
- Soft-start function
- Protection against feedback loop disconnection
- Inhibit for zero current consumption
- Thermal shutdown
- Zero load current operation
- Adjustable switching frequency up to 300kHz
- Precise 3.3V (±1%) internal reference voltage
Applications
The L4971 is suitable for a wide range of applications, including:
- Industrial power supplies
- Automotive systems
- Telecommunication equipment
- Consumer electronics requiring high-efficiency DC-DC conversion
Q & A
- What is the maximum output current of the L4971?
The L4971 can deliver up to 1.5A of output current.
- What is the input voltage range of the L4971?
The input voltage range is from 8V to 55V.
- How is the output voltage of the L4971 adjusted?
The output voltage can be adjusted from 3.3V to 50V using a simple external divider.
- What are the package options for the L4971?
The L4971 is available in DIP-8 and SO-16W packages.
- What is the switching frequency range of the L4971?
The switching frequency can be adjusted up to 300kHz.
- Does the L4971 have built-in protection features?
Yes, it includes features such as pulse-by-pulse current limiting, hiccup mode for short circuit protection, thermal shutdown, and protection against feedback loop disconnection.
- How does the soft-start function work in the L4971?
The soft-start function is controlled by a capacitor connected between the SS_INH pin and ground, which determines the soft start time.
- What is the purpose of the inhibit function in the L4971?
The inhibit function allows for zero current consumption by disabling the device when the SS_INH pin is grounded.
- What is the internal reference voltage of the L4971?
The internal reference voltage is 3.3V with a precision of ±1%.
- What are the typical operating temperatures for the L4971?
The operating temperature range is from -40°C to 150°C.
