Texas Instruments TPS543820RPYR

Overview

TPS543820RPYR from Texas Instruments is an 8-A synchronous step-down DC/DC converter with internally compensated advanced current mode (ACM) control, operating from 4 V to 18 V input and delivering 0.5 V to 7 V output at up to 2.2 MHz switching frequency. It integrates 25-mΩ high-side and 6.5-mΩ low-side MOSFETs, features ±0.5% reference accuracy over –40°C to 150°C, and supports monotonic start-up into pre-biased outputs - ideal for compact power rails in optical networking and wireless infrastructure.

For engineers reviewing the TPS543820RPYR datasheet, TPS543820RPYR pinout, TPS543820RPYR application, or TPS543820RPYR equivalent, key selection considerations include its 2.5-mm × 3-mm VQFN-HR package, five selectable switching frequencies (500 kHz–2.2 MHz), internal ramp tuning via MODE pin resistor, programmable current limit (6-A/8-A), and synchronization capability via SYNC/FSEL pin - all critical for high-density, thermally constrained designs.

Technical Context

The TPS543820RPYR implements fixed-frequency Advanced Current Mode (ACM) control using an emulated peak current architecture with internal ramp generation - eliminating need for external compensation while enabling stable operation with low-ESR MLCC output capacitors. Its three programmable ramp options (via MODE pin resistor) directly tune loop bandwidth for specific inductor-capacitor combinations.

Control logic integrates synchronized soft-start (0.5/1/2/4 ms), adjustable EN-based UVLO, and comprehensive fault protection including output OVP/UVP, input UVLO, overcurrent (HS/LS), and thermal shutdown at 165°C with 12°C hysteresis - all managed within a single 14-pin HotRod™ VQFN-HR package optimized for thermal performance and EMI reduction.

Key Specifications

Pinout & Package

TPS543820RPYR uses a 2.5-mm × 3-mm, 14-pin VQFN-HR (HotRod™) package with exposed thermal pad and 0.5-mm pitch. The package enables low-inductance power routing and enhanced thermal dissipation via bottom-side copper connection.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck converter applications.

Compared with TPS543820RPYR, TPS543620RPYR provides identical functionality at reduced current and efficiency, while TPS543320RPYR extends current capability and thermal margin - all three enable drop-in scalability across 6-A, 8-A, and 12-A power tiers without redesigning the PCB layout.

Availability

TPS543820RPYR is available at Aetrix Electronics and suitable for optical networking equipment, 5G wireless infrastructure, and medical imaging systems requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for TPS543820RPYR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with over 90 years of innovation in high-reliability electronic components.

The TPS543820RPYR belongs to TI's SWIFT™ synchronous buck converter family, engineered for high-density, high-efficiency point-of-load regulation in thermally demanding communications and industrial applications - emphasizing integration, thermal robustness, and system-level timing flexibility.

FAQ

What is the maximum recommended switching frequency for TPS543820RPYR in continuous operation?

The TPS543820RPYR supports a maximum switching frequency of 2.2 MHz in continuous operation, achieved by connecting a 4.99-kΩ resistor from SYNC/FSEL to AGND. At this frequency, the device maintains >85% efficiency at 12 V input to 1 V output with appropriate output filter selection (e.g., 470-nH inductor, 22-μF MLCC). Operation above 2.2 MHz is not specified and may compromise stability or thermal performance.

Does TPS543820RPYR support monotonic start-up into a pre-biased output, and how is it implemented?

Yes, TPS543820RPYR supports monotonic start-up into pre-biased outputs without reverse current flow. This is implemented through internal control logic that disables the high-side MOSFET until the feedback voltage reaches the soft-start target, allowing the output capacitor to charge only from the input rail. No external components are required - the feature is enabled by default and verified across –40°C to +150°C.

How does the MODE pin resistor affect current limit selection in TPS543820RPYR?

The MODE pin resistor selects between two current limit modes: R_MODE = 1.78 kΩ configures 8-A operation (HS peak current = 12.2 A typical), while R_MODE = 22.1 kΩ configures 6-A operation (HS peak current = 9.0 A typical). This adjustment changes both overcurrent trip thresholds and soft-start rate, enabling one hardware design to serve multiple power-tier requirements without changing the IC.

Can TPS543820RPYR be synchronized to an external clock, and what are the valid frequency and duty-cycle ranges?

Yes, TPS543820RPYR can be synchronized to an external clock applied to the SYNC/FSEL pin. Valid external clock frequency range is 400 kHz to 2600 kHz, with duty cycle between 20% and 80%. The device locks to the external clock within four consecutive cycles and defaults to its internal oscillator frequency if synchronization is lost - ensuring seamless fallback without output disruption.

What thermal metrics define the package performance of TPS543820RPYR, and how do they impact PCB layout?

TPS543820RPYR's VQFN-HR package has R_θJA = 58.9°C/W (standard JEDEC board) and R_θJB = 7.3°C/W (junction-to-board), indicating strong thermal coupling to the PCB. Effective layout requires a minimum 120 mm² exposed thermal pad connected to ≥2 internal ground planes via ≥8 thermal vias (0.3-mm diameter), plus low-inductance VIN/PGND routing - critical to maintain <150°C junction temperature at 8-A load.