Overview
The LM2575-5.0BN is a step-down (buck) switching voltage regulator produced by Texas Instruments, though it may be distributed through various channels including Microchip Technology. This integrated circuit is designed to simplify the creation of switching power supplies by providing all the necessary active functions in a single package. It is capable of delivering up to 1 A of load current with excellent line and load regulation. The LM2575-5.0BN operates over a wide input voltage range of 4.75 V to 40 V and is available in fixed output voltages, including the 5.0 V version specified here.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Regulator Type | Step Down (Buck) | |
| Minimum Input Voltage | 4.75 | V |
| Maximum Input Voltage | 40 | V |
| Output Voltage | 5.0 | V |
| Maximum Output Current | 1 | A |
| Operating Frequency | 52 kHz (Typical) | |
| Line Regulation | ±4% (Max) Over Line, Load, and Temperature Conditions | |
| Thermal Shutdown | Yes | |
| ON/OFF Pin Logic | Active Low Enable | |
| Maximum Junction Temperature | 150 °C | |
| Operating Temperature Range | –40°C to 125°C |
Key Features
- Adjustable Output Voltage: Although the LM2575-5.0BN is a fixed output version, the LM2575 series offers adjustable output versions with a range of 1.23 V to 37 V.
- Wide Input Voltage Range: Operates from 4.75 V to 40 V.
- High Efficiency: Up to 88% typical efficiency.
- Internal Frequency Compensation: No external frequency compensation is required.
- Fixed-Frequency Oscillator: 52 kHz typical frequency.
- Cycle-by-Cycle Current Limiting: Protects against overcurrent conditions.
- Thermal Shutdown and Current-Limit Protection: Ensures device safety during overload or high-temperature conditions.
- TTL Shutdown Capability: Allows for manual shutdown via an external ON/OFF pin.
- Minimal External Components: Requires only four to six external components for operation.
Applications
- Simple High-Efficiency Step-Down (Buck) Regulator: Ideal for general-purpose power supply designs.
- Pre-Regulator for Linear Regulators: Can be used to pre-regulate the input voltage for linear regulators.
- On-Card Switching Regulators: Suitable for compact, on-card power supply solutions.
- Positive-to-Negative Converter (Buck-Boost): Can be configured for buck-boost applications.
- Battery Chargers: Used in power supplies for battery charging systems.
Q & A
- What is the input voltage range of the LM2575-5.0BN?
The input voltage range is from 4.75 V to 40 V.
- What is the maximum output current of the LM2575-5.0BN?
The maximum output current is 1 A.
- What is the typical operating frequency of the LM2575-5.0BN?
The typical operating frequency is 52 kHz.
- Does the LM2575-5.0BN have thermal shutdown protection?
Yes, it has thermal shutdown and current-limit protection.
- How is the output voltage set for the adjustable version of the LM2575?
The output voltage is set by two external resistors (R1 and R2) for the adjustable version.
- What is the purpose of the ON/OFF pin on the LM2575-5.0BN?
The ON/OFF pin allows for manual shutdown of the device by applying a high-level TTL or CMOS voltage.
- What is the maximum junction temperature for the LM2575-5.0BN?
The maximum junction temperature is 150 °C.
- What type of logic does the ON/OFF pin use?
The ON/OFF pin uses active low logic.
- Why is it important to keep the programming resistors close to the regulator?
To minimize noise pickup, the programming resistors should be in close proximity to the regulator and each should be less than 100 kΩ.
- What is the typical quiescent current in standby mode?
The typical quiescent current in standby mode is 50 µA.
