Step-down Voltage Regulator Texas Instruments LM2676S-5.0, fixed 5 V output, input 8–40 V, TO-263-7

The Texas Instruments LM2676S-5.0 is a fixed-output step-down (buck) switching regulator that delivers a stable 5 V output from input voltages between 8 V and 40 V. Housed in a TO-263-7 surface-mount package, the device is intended for efficient DC–DC conversion where a regulated 5 V rail is required. The regulator integrates switching control and output stage components to simplify power-supply design and reduce external component count.

Advantages

The LM2676S-5.0 offers high-efficiency switching operation that reduces power dissipation compared with linear regulators when stepping down from higher input voltages. Its fixed 5 V output removes the need for external reference adjustment and simplifies board layout. The TO-263-7 package provides thermal performance suitable for many compact power modules, and the integrated control functions reduce the number of discrete parts needed for a complete regulator solution.

Suitable for

• Embedded systems requiring a reliable 5 V supply
• Industrial control electronics with higher supply voltages
• Automotive electronics and subsystems where 12 V or 24 V must be converted to 5 V
• Power-supply modules and DC–DC conversion boards

Key specifications

• Output voltage: fixed 5.0 V
• Input voltage range: 8 V to 40 V
• Topology: step-down (buck) switching regulator
• Package: TO-263-7 (surface-mount power package)
• Integrated switching control and output stage for simplified external components

How to use

Place the LM2676S-5.0 on the PCB following the recommended footprint for the TO-263-7 package and route power and ground planes to optimize thermal dissipation. Select the inductor, diode, input and output capacitors according to the device application guidelines to achieve stable regulation and low output ripple. Connect the input supply (8–40 V) to the regulator input pin and take the regulated 5 V output from the output pin; observe correct polarity and layout best practices for switching regulators. Follow the manufacturer's application notes for recommended external component values, compensation and layout to ensure reliable operation.

Usage recommendations

For best thermal performance and minimum EMI, use recommended component values and layout practices from the device documentation. Provide adequate heat sinking or copper area on the PCB when operating near the upper limits of input voltage or output current, and include input filtering to protect against supply transients.