Overview
The L5973D is a step-down monolithic power switching regulator produced by STMicroelectronics. It is designed to deliver high current levels, with a minimum switch current limit of 2.5 A, enabling it to supply more than 2 A DC current to the load under various application conditions. The output voltage can be adjusted from 1.235 V to 35 V, making it versatile for a wide range of applications. The device features an internal P-channel D-MOS transistor with a typical Rdson of 250 mΩ, which minimizes the need for external components. The L5973D operates with an internally fixed switching frequency of 250 kHz and is particularly suitable for 5 V bus applications, common in computer-related systems.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Operating Input Voltage | 4 | - | 36 | V |
| Output Voltage Range | 1.235 | - | 35 | V |
| Switch Current Limit | 2.5 | - | 3.5 | A |
| Switching Frequency | 212 | 250 | 280 | kHz |
| Mosfet On Resistance (Rdson) | 0.250 | - | 0.5 | Ω |
| Operating Junction Temperature | -40 | - | 150 | °C |
| Thermal Resistance (Rth(j-amb)) | - | - | 40 | °C/W |
Key Features
- Internal P-channel D-MOS transistor with a typical Rdson of 250 mΩ to minimize external component size.
- Internally fixed switching frequency of 250 kHz.
- Output voltage adjustable from 1.235 V to 35 V.
- Low dropout operation with 100% duty cycle capability.
- Internal current limiting and frequency modulation for effective short circuit protection.
- Inhibit feature for zero current consumption in standby mode.
- Synchronization capability for master/slave operation.
- Protection against feedback disconnection and thermal shutdown.
- SO8 package with exposed frame to reduce thermal resistance.
Applications
- Consumer electronics: Set-top boxes, DVD players, TVs, VCRs, car radios, LCD monitors.
- Networking: XDSL, modems, DC-DC modules.
- Computer systems: Printers, audio/graphic cards, optical storage, hard disk drives.
- Industrial applications: Chargers, car batteries, DC-DC converters.
Q & A
- What is the minimum input voltage for the L5973D?
The minimum input voltage for the L5973D is 4 V.
- What is the range of output voltage for the L5973D?
The output voltage can be adjusted from 1.235 V to 35 V.
- What is the typical switching frequency of the L5973D?
The typical switching frequency is 250 kHz.
- What is the maximum switch current limit of the L5973D?
The maximum switch current limit is 3.5 A.
- Does the L5973D have thermal protection?
Yes, the L5973D features thermal shutdown protection.
- How does the inhibit feature work on the L5973D?
The inhibit feature disables the device when the INH pin is higher than 2.2 V, reducing power consumption to less than 100 μA.
- What is the thermal resistance (Rth(j-amb)) of the L5973D in its SO8 package?
The thermal resistance is approximately 40 °C/W.
- Can the L5973D operate in synchronization with other devices?
Yes, the L5973D has synchronization capability for master/slave operation.
- What are some common applications for the L5973D?
Common applications include consumer electronics, networking devices, computer systems, and industrial applications.
- What is the typical Rdson of the internal P-channel D-MOS transistor in the L5973D?
The typical Rdson is 250 mΩ.
