Overview
The L4978D013TR, produced by STMicroelectronics, is a step-down monolithic power switching regulator. This device is capable of delivering up to 2A of current at output voltages ranging from 3.3V to 50V, which can be adjusted using a simple external divider. Realized in BCD mixed technology, the L4978D013TR utilizes an internal power D-MOS transistor to achieve high efficiency and high switching speeds. The regulator operates over a wide input voltage range of 8V to 55V, making it suitable for a variety of applications.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Operating Input Voltage Range | 8 | - | 55 | V |
| Output Voltage Range | 3.3 | - | 50 | V |
| Maximum Output Current | - | - | 2 | A |
| Switching Frequency | 90 | 100 | 110 | KHz |
| Internal Reference Voltage | 3.33 | 3.36 | 3.39 | V |
| Dropout Voltage | 0.58 | 0.733 | 1.173 | V |
| Maximum Duty Cycle | 95 | 97 | - | % |
| Thermal Resistance Junction to Ambient | - | - | 90 (DIP-8), 110 (SO16) | °C/W |
| Junction and Storage Temperature | -40 | - | 150 | °C |
Key Features
- Up to 2A 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 using an external divider
- Switching frequency adjustable up to 300KHz
- Voltage feedforward regulation
- Zero load current operation
- Internal current limiting (pulse-by-pulse and hiccup mode)
- Inhibit for zero current consumption
- Protection against feedback disconnection
- Thermal shutdown
- Soft start function
Applications
The L4978D013TR is suitable for a wide range of applications requiring efficient and adjustable DC-DC conversion. These include:
- Power supplies for industrial and consumer electronics
- Telecommunication equipment
- Automotive systems
- Medical devices
- High-efficiency power conversion in various embedded systems
Q & A
- What is the maximum output current of the L4978D013TR?
The maximum output current of the L4978D013TR is 2A.
- What is the operating input voltage range of the L4978D013TR?
The operating input voltage range is from 8V to 55V.
- How is the output voltage adjusted on the L4978D013TR?
The output voltage can be adjusted from 3.3V to 50V using a simple external resistive divider.
- What is the switching frequency range of the L4978D013TR?
The switching frequency can be adjusted up to 300KHz.
- Does the L4978D013TR have thermal protection?
- What are the package options for the L4978D013TR?
The device is available in DIP-8 and SO16W packages, with the SO16W also available in tape and reel.
- What is the internal reference voltage of the L4978D013TR?
The internal reference voltage is 3.3V with a ±1% tolerance.
- Does the L4978D013TR have current limiting features?
- How does the soft start function work on the L4978D013TR?
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 typical efficiency of the L4978D013TR?
The typical efficiency is around 87% for an output voltage of 3.3V and an output current of 2A.
