Texas Instruments TPS53353DQPR

Overview

TPS53353 from Texas Instruments is a D-CAP™ mode, 20-A synchronous buck DC-DC converter with integrated NexFET™ power MOSFETs (5.5 mΩ high-side / 2.2 mΩ low-side), 0.6 V ±0.5% reference, and Eco-mode™ for light-load efficiency. It operates from 1.5 V to 15 V conversion input and delivers 0.6 V to 5.5 V output at up to 20 A continuous current - used in FPGA core voltage regulation where fast transient response and high efficiency at 12 V → 1.1 V are critical.

For engineers reviewing the TPS53353 datasheet, TPS53353 pinout, TPS53353 application, or TPS53353 equivalent, key selection criteria include its adaptive on-time D-CAP™ control architecture, selectable 250 kHz–1 MHz switching frequency via RF pin resistor, integrated 5-V LDO (VREG), pre-biased start-up capability, and open-drain PGOOD with 1-ms delay - all validated for enterprise server point-of-load designs.

Technical Context

The TPS53353 implements adaptive on-time D-CAP™ control that eliminates external compensation by sensing output capacitor ESR, enabling ultra-fast load-step response without loop stability tuning. Its internal 0.6-V reference achieves ±0.5% accuracy over –40°C to 85°C, and the MODE pin simultaneously configures soft-start time (0.7–5.6 ms) and FCCM/skip-mode operation.

Switching frequency is set via resistor on RF pin (GND or VREG), yielding eight discrete values from 250 kHz to 1 MHz; off-time is PWM-controlled using ramp-compensated comparator logic. Overcurrent protection uses TRIP pin with thermally compensated 10 µA current source (4700 ppm/°C) to set OCL threshold as VOCL = VTRIP/32.

Key Specifications

Pinout & Package

TPS53353 is housed in a 5.0 mm × 6.0 mm, 22-pin LSON-CLIP (QFN) package with exposed PowerPAD™ thermal pad for enhanced heat dissipation. The package is RoHS-compliant and rated for –40°C to 85°C ambient operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS53355DQPR and TPS548B28RMLR, the TPS53353 provides the best trade-off of proven reliability, full feature set (Eco-mode, D-CAP™, pre-bias), and broad industrial temperature support - making it ideal for enterprise infrastructure where long-term supply continuity and qualification stability are critical.

Availability

TPS53353 is available at Aetrix Electronics and suitable for enterprise rack servers, wired networking switches and routers, and ASIC/FPGA core voltage regulation requiring stable component supply across multi-year production cycles.

Supply support for TPS53353 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 50 years of innovation in high-reliability power conversion.

The TPS53353 belongs to TI's SWIFT™ synchronous buck converter family, designed specifically for high-efficiency, low-voltage point-of-load applications in computing, networking, and storage infrastructure where fast transient response and minimal external components are essential.

FAQ

What is the maximum continuous output current supported by the TPS53353?

The TPS53353 supports 20 A continuous output current under recommended operating conditions (–40°C to 85°C, proper PCB layout with thermal vias). This rating assumes use of the integrated 5.5 mΩ high-side and 2.2 mΩ low-side NexFET™ MOSFETs, adequate input capacitance, and appropriate output inductor sizing per TI's SLUSAK2D design guidelines. Derating applies above 60°C ambient.

Does the TPS53353 require external compensation components?

No, the TPS53353 does not require external compensation components due to its D-CAP™ adaptive on-time control architecture, which senses output capacitor ESR to close the feedback loop. This eliminates the need for type-II or type-III compensation networks, reducing BOM count and simplifying layout - a key advantage confirmed in Section 7.3.2 of the TPS53353 datasheet.

How is the switching frequency selected on the TPS53353?

The switching frequency of the TPS53353 is selected using an external resistor connected between the RF pin and either GND or VREG. Eight discrete frequencies from 250 kHz to 1 MHz are supported, with specific values defined in Table 7-1 of the datasheet (e.g., 300 kHz with 187 kΩ to GND, 650 kHz with 866 kΩ to VREG). An open RF pin defaults to 500 kHz.

Can the TPS53353 start up into a pre-charged output capacitor?

Yes, the TPS53353 supports pre-biased start-up, allowing safe operation when the output voltage is already present before enable. This is confirmed in Figure 6-14 (prebias start-up waveforms) and Section 7.3.4 of the datasheet. During pre-bias start-up, the device prevents reverse current flow through the low-side MOSFET by controlling gate timing based on sensed LL node voltage.

What protection features are integrated into the TPS53353?

The TPS53353 integrates overvoltage (OVP), undervoltage (UVP), overtemperature (145°C shutdown), overcurrent (TRIP-pin programmable), and UVLO protection. OVP triggers at 115–125% of VOUT with 1 µs propagation delay; UVP activates at 65–75% with 1–1.2 ms delay; thermal shutdown includes 10°C hysteresis. All protections are hardware-based and do not rely on external monitoring circuits.