Overview
The L4971 is a step-down monolithic power switching regulator produced by STMicroelectronics. It is designed to deliver up to 1.5A of output current at a voltage range between 3.3V and 50V. The device features a precise internal reference voltage of 3.3V (±1%) and supports adjustable output voltages through an external resistive divider. The L4971 operates with an input voltage range from 8V to 55V and offers various protection and control features, including thermal shutdown, soft start, and internal current limiting.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Operating Input Voltage | 8 to 55 | V |
| Output Voltage Range | 3.3 to 50 | V |
| Maximum Output Current | 1.5 | A |
| Switching Frequency | Up to 300 kHz | kHz |
| Internal Reference Voltage | 3.3V (±1%) | V |
| Thermal Shutdown | Yes | |
| Soft Start | Yes | |
| Package Options | DIP8, SO16W | |
| Junction and Storage Temperature | -40 to 150 °C | °C |
Key Features
- Up to 1.5A step-down converter
- Operating input voltage from 8V to 55V
- Precise 3.3V (±1%) internal reference voltage
- Output voltage adjustable from 3.3V to 50V
- Switching frequency adjustable up to 300 kHz
- Voltage feedforward and zero load current operation
- Internal current limiting (pulse-by-pulse and hiccup mode)
- Inhibit for zero current consumption
- Protection against feedback disconnection
- Thermal shutdown and soft start function
Applications
The L4971 is suitable for a variety of applications requiring efficient and reliable DC-DC conversion, such as:
- Power supplies for industrial and consumer electronics
- DC-DC converters in automotive systems
- Telecommunication equipment
- Medical devices requiring stable and efficient power supply
- Embedded systems and IoT devices
Q & A
- What is the maximum output current of the L4971?
The maximum output current of the L4971 is 1.5A.
- What is the input voltage range for the L4971?
The input voltage range for the L4971 is from 8V to 55V.
- How can the output voltage be adjusted?
The output voltage can be adjusted using an external resistive divider connected to the feedback input pin.
- What is the switching frequency range of the L4971?
The switching frequency of the L4971 can be adjusted up to 300 kHz using external resistors and capacitors.
- Does the L4971 have thermal protection?
Yes, the L4971 features thermal shutdown to protect against overheating.
- What are the package options for the L4971?
The L4971 is available in DIP8 and SO16W packages.
- How does the soft start function work?
The soft start function is controlled by a capacitor connected to the SS_INH pin, which determines the soft start time.
- What is the purpose of the inhibit function?
The inhibit function allows the device to be disabled, resulting in zero current consumption when the SS_INH pin is grounded.
- Does the L4971 have internal current limiting?
Yes, the L4971 features internal current limiting in both pulse-by-pulse and hiccup modes.
- What is the junction and storage temperature range for the L4971?
The junction and storage temperature range for the L4971 is -40 to 150 °C.
