TPS56x24x Synchronous Step-Down Converter

Introduction

Texas Instruments’ TPS56x24x family comprises synchronous step-down DC-DC converters designed for compact power conversion from 3 V to 17 V input rails. The devices combine integrated MOSFETs, 1.2 MHz switching, and D-CAP3 control in a 1.6 mm × 1.6 mm SOT-563 package, targeting designs where power density and a small external component footprint matter.

The family supports regulated outputs from 0.6 V to 10 V and continuous load currents up to 3 A, depending on the selected device. TPS562242B is rated for up to 2 A, while TPS563242 and TPS563247 support up to 3 A.

What it does

The TPS56x24x converts a higher DC input voltage into a lower regulated output voltage using synchronous buck topology. Its integrated MOSFETs have specified resistances of 55.0 mΩ and 24.3 mΩ, eliminating the need for external switching FETs.

D-CAP3 control supports low-ESR output capacitors and does not require external compensation. The converters operate at a 1.2 MHz switching frequency and support up to a 95% duty cycle. A 0.6 V reference is specified with ±1% accuracy at +25°C and ±1.5% accuracy across a –40°C to +125°C junction-temperature range.

The family includes a 1.6 ms typical soft-start time and 100 µA quiescent current. Protection coverage includes overvoltage protection (OVP), overcurrent protection (OCP), undervoltage lockout (UVLO), overtemperature protection (OTP), and undervoltage protection (UVP). Specific variants also provide Eco-mode or forced continuous conduction mode (FCCM) operation.

Applications

Potential uses based on the stated input range, output range, and current capability include:

• Point-of-load rails derived from 3 V to 17 V distribution voltages
• Compact logic, processor, FPGA, or ASIC supply rails requiring outputs down to 0.6 V
• Local 2 A or 3 A DC-DC conversion stages
• Systems requiring a small synchronous buck regulator with integrated MOSFETs
• Designs using low-ESR output capacitors and seeking to avoid external loop-compensation components

Design considerations

The TPS56x24x is supplied in a 1.6 mm × 1.6 mm SOT-563 package, which supports dense layouts but requires appropriate PCB footprint and thermal design for the intended load and operating temperature. Device selection should account for the current distinction within the family: TPS562242B supports up to 2 A continuous output current, while TPS563242 and TPS563247 support up to 3 A.

The input supply must remain within the specified 3 V to 17 V range, and the required regulated rail must fall between 0.6 V and 10 V. Designers can use low-ESR output capacitors with the D-CAP3 control scheme without adding external compensation, while variant-specific Eco-mode or FCCM behavior should be considered when choosing a device.

Availability and further information

The source/distributor and datasheet links on this page provide further information on the TPS56x24x family, including variant-specific operating modes, electrical characteristics, recommended external components, and package details.