Overview
The L4972AD is a high-performance stepdown monolithic power switching regulator produced by STMicroelectronics. This device is realized using BCD (Bipolar, CMOS, DMOS) mixed technology, which integrates isolated vertical DMOS power transistors along with mixed CMOS/Bipolar transistors. The L4972AD is capable of delivering up to 2A of output current with an adjustable output voltage ranging from 5.1V to 40V. It features advanced diagnostic and control functions, making it particularly suitable for microprocessor-based systems.
Key Specifications
| Parameter | Min. | Max. | Unit | |
|---|---|---|---|---|
| Input Voltage Range | 15 | - | 50 | V |
| Output Voltage | 5 | 5.1 | 5.2 | V |
| Output Current | - | - | 2 | A |
| Line Regulation | 12 | - | 30 | mV |
| Load Regulation | 7 | - | 20 | mV |
| Switching Frequency | - | - | 200 kHz | - |
| Thermal Shutdown | - | - | 150°C | - |
Key Features
- 2A output current capability
- Adjustable output voltage from 5.1V to 40V
- Internal feed-forward line regulation
- Internal current limiting and thermal shutdown
- Precise 5.1V ± 2% on-chip reference voltage
- Reset and power fail functions for microprocessors
- Input/output sync pin for multiple device synchronization
- Under voltage lockout with hysteresis
- PWM latch for single pulse per period
- Very high efficiency and fast switching times
- Soft start function to prevent output overcurrents at turn-on
Applications
The L4972AD is designed for use in a variety of applications, including:
- Microprocessor-based systems requiring reliable power supply with diagnostic features
- Multiple supply systems where synchronization between regulators is necessary
- High-efficiency power conversion in industrial and automotive systems
- Systems requiring adjustable output voltages with precise regulation
Q & A
- What is the maximum output current of the L4972AD?
The L4972AD can deliver up to 2A of output current.
- What is the adjustable output voltage range of the L4972AD?
The output voltage can be adjusted from 5.1V to 40V.
- What is the switching frequency range of the L4972AD?
The switching frequency can be up to 200 kHz.
- Does the L4972AD have thermal protection?
- What are the package options for the L4972AD?
The device is available in PowerDIP20 (16+2+2) and SO20 packages.
- How does the soft start function work in the L4972AD?
The soft start function prevents output overcurrents at turn-on by linearly increasing the output voltage using an external capacitor and an internal constant current source.
- What is the purpose of the reset and power fail functions?
These functions provide an output signal to indicate the status of the system to microprocessors, ensuring safe operation.
- Can multiple L4972AD devices be synchronized?
- What is the line regulation capability of the L4972AD?
The device offers line regulation of 12 mV to 30 mV over the input voltage range.
- How does the current limiting function work in the L4972AD?
The current limiting function senses the load current and limits it to prevent overcurrent conditions, ensuring constant current output during overload or short circuit.
