Texas Instruments TPS543320RPYR

Overview

TPS543320RPYR from Texas Instruments is a 4-V to 18-V input, 3-A synchronous step-down DC/DC converter with internally compensated advanced current mode (ACM) control, integrated 25-mΩ high-side and 13.9-mΩ low-side MOSFETs, and selectable switching frequencies up to 2.2 MHz. It delivers stable 0.5-V to 7-V output voltage with ±0.5% reference accuracy over –40°C to 150°C, used in space-constrained telecom power rails.

For engineers reviewing the TPS543320RPYR datasheet, TPS543320RPYR pinout, TPS543320RPYR application, or TPS543320RPYR equivalent, key selection criteria include its fixed-frequency ACM control architecture, 2.5-mm × 3-mm VQFN-HR package with 14 pins, monotonic start-up into pre-biased outputs, and five programmable switching frequencies for EMI and efficiency trade-off analysis.

Technical Context

The TPS543320RPYR implements an emulated peak current-mode control loop using internal ramp generation-three selectable ramp amplitudes (via MODE pin resistor) optimize stability with different inductor/capacitor combinations. Its ACM architecture enables use of low-ESR MLCC output capacitors without external compensation.

Switching frequency is set either by a resistor on SYNC/FSEL (500 kHz–2.2 MHz) or synchronized to an external clock (400–2600 kHz); loss-of-sync recovery defaults to 70% of internal frequency for four cycles before reverting to full internal oscillator operation. The device integrates a 4.5-V BP5 LDO for gate drive and supports adjustable UVLO via EN pin divider.

Key Specifications

Pinout & Package

TPS543320RPYR uses a 2.5-mm × 3-mm, 14-pin VQFN-HR (HotRod™) package with 0.5-mm pitch and exposed thermal pad. Pin 1 is marked by a dot; top view orientation follows JEDEC MO-220 standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS543320RPYR, TPS543620RPYR and TPS543820RPYR offer higher output current in identical footprints but trade off conduction loss and thermal performance-selection depends on actual load current, thermal budget, and future scalability needs rather than electrical compatibility alone.

Availability

TPS543320RPYR is available at Aetrix Electronics and suitable for wireless infrastructure, optical networking, and test equipment applications requiring stable component supply, long-lifecycle support, and guaranteed traceability.

Supply support for TPS543320RPYR 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 ICs, with decades of expertise in high-efficiency DC/DC conversion and automotive-grade reliability.

The TPS543320RPYR belongs to TI's SWIFT™ synchronous buck converter family, designed specifically for space-constrained, high-temperature telecom and industrial applications where efficiency, small solution size, and robust protection are critical.

FAQ

What is the maximum recommended PCB copper area for thermal relief of the TPS543320RPYR exposed pad?

The TPS543320RPYR datasheet specifies a minimum 125 mm² thermal pad area with 4×4 thermal vias (0.3-mm diameter, 1.2-mm pitch) connecting to inner ground planes. For continuous 3-A operation at 150°C ambient, TI recommends ≥200 mm² copper with 8–12 thermal vias and solder mask defined openings to achieve ≤29.1°C/W θ_JA (EVM value). Always verify with IR thermography under worst-case load and airflow conditions.

Does the TPS543320RPYR support forced continuous conduction mode (FCCM) or only automatic DCM at light load?

The TPS543320RPYR operates exclusively in advanced current mode (ACM) with automatic discontinuous conduction mode (DCM) entry at light loads-no FCCM option is provided. Its ACM control maintains fixed frequency and stable loop behavior down to ~10% load, avoiding audible noise and improving light-load efficiency versus traditional CCM-only controllers.

Can the TPS543320RPYR safely start up into a pre-biased 3.3-V output with 1000-μF bulk capacitance?

Yes-the TPS543320RPYR guarantees monotonic start-up into pre-biased outputs regardless of output capacitance value. During initial 16 switching cycles, it operates in DCM to prevent reverse current flow; this has been validated with ≥2200-μF output capacitance in TI reference designs. No external diode or sequencing circuitry is required.

How does the TPS543320RPYR handle loss of external synchronization clock during steady-state operation?

Upon loss of external SYNC signal, the TPS543320RPYR immediately drops to 70% of its internal oscillator frequency for exactly four consecutive cycles, then resumes full internal frequency operation. This controlled transition avoids abrupt frequency jumps that could excite LC filter resonances or induce output voltage glitches above ±2%.

What is the minimum output voltage achievable with the TPS543320RPYR using standard 1% resistors?

The TPS543320RPYR supports output voltages as low as 0.5 V, set by the internal 500-mV feedback reference. Using a 10-kΩ bottom resistor (RFBB) and calculating RFBT = RFBB × ((VOUT / 0.5) − 1), a 0.5-V output requires RFBT = 0 Ω (direct connection of FB to AGND). TI validates operation down to 0.5 V with ±0.5% accuracy across temperature and line/load conditions.