Overview
The L5973AD is a step-down monolithic power switching regulator produced by STMicroelectronics. It features a switch current limit of 2A, enabling it to deliver more than 1.5 A DC current to the load, depending on the application conditions. The output voltage can be adjusted from 1.235 V to 35 V. The device is packaged in an SO8 package with an exposed frame, which reduces the thermal resistance (RthJA) to approximately 40 °C/W. This regulator is particularly suitable for applications requiring a 5 V bus, such as computer-related applications, due to its minimum input voltage of 4 V.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Switch Current Limit | 2 A | A |
| Output Voltage Range | 1.235 V to 35 V | V |
| Input Voltage Range | 4 V to 36 V | V |
| Switching Frequency | 500 kHz | kHz |
| Reference Voltage | 3.3 V (±2%) | V |
| Thermal Resistance (RthJA) | Approximately 40 °C/W | °C/W |
| Operating Junction Temperature Range | -40 to 150 °C | °C |
| Package Type | PowerSO-8 (Exposed pad) |
Key Features
- Inhibit for zero current consumption
- Internal current limiting
- Protection against feedback disconnection
- Synchronization
- Thermal shutdown
- Voltage feedforward
- 500 kHz Internally fixed frequency
- 2 A Internal switch
- Low dropout operation: 100% duty cycle
- Zero load current operation
- Pulse by pulse current limit with internal frequency modulation for constant current short circuit protection
Applications
- Consumer: STB, DVD, TV, VCR, car radio, LCD monitors
- Networking: XDSL, modems, DC-DC modules
- Computer: printers, audio/graphic cards, optical storage, hard disk drive
- Industrial: chargers, car battery, DC-DC converters
Q & A
- What is the maximum switch current limit of the L5973AD?
The maximum switch current limit of the L5973AD is 2 A.
- What is the adjustable output voltage range of the L5973AD?
The output voltage can be adjusted from 1.235 V to 35 V.
- What is the input voltage range for the L5973AD?
The input voltage range is from 4 V to 36 V.
- What is the switching frequency of the L5973AD?
The switching frequency is internally fixed at 500 kHz.
- What is the reference voltage of the L5973AD?
The reference voltage is 3.3 V with a ±2% tolerance.
- How does the inhibit feature work on the L5973AD?
The inhibit feature allows the device to be put into standby mode. With the INH pin higher than 2.2 V, the device is disabled, and with the INH pin lower than 0.8 V, the device is enabled.
- What kind of thermal protection does the L5973AD have?
The L5973AD has thermal shutdown protection that turns off the power stage if the junction temperature exceeds 150 °C.
- What types of current protection are available in the L5973AD?
The L5973AD features pulse by pulse current limit and frequency fold back for current protection.
- What is the typical thermal resistance (RthJA) of the L5973AD in its SO8 package?
The typical thermal resistance (RthJA) is approximately 40 °C/W.
- What are some common applications for the L5973AD?
Common applications include consumer electronics, networking devices, computer peripherals, and industrial equipment.
