TPS5450DDAR - 5A 36V Buck Converter 500kHz | Texas Instruments
MPN: TPS5450DDAR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.95 | $3.95 |
| 10 | $3.56 | $35.60 |
| 100 | $3.16 | $316.00 |
| 500 | $2.85 | $1,425.00 |
| 1,000 | $2.55 | $2,550.00 |
TPS5450DDAR Overview
A buck converter, or step-down converter, is a DC-DC switching regulator that efficiently reduces a higher input voltage to a lower regulated output using a switching element, an inductor, and input/output capacitors. Within the power management IC hierarchy, buck converters are fundamental point-of-load building blocks: voltage regulator -> switching regulator -> buck converter -> power management IC. The SWIFT family from TI is known for high efficiency, fast transient response, and a simplified design flow.
Key features include a fixed 500kHz switching frequency that allows small external inductors and capacitors, an integrated low-resistance high-side N-channel MOSFET that minimizes external component count, cycle-by-cycle overcurrent protection, programmable soft-start via the SS/TR pin, an enable (ENA) pin for power sequencing, and internal thermal shutdown protection.
Technically, the TPS5450 uses internally compensated voltage-mode PWM control with a high-performance voltage error amplifier providing tight output regulation. Typical conversion efficiency exceeds 90 percent at moderate loads, which minimizes heat generation. The PowerPAD (HSOIC-8, 3.90mm body width) construction provides a low thermal impedance path when soldered to an adequate PCB copper pour, allowing full 5A continuous operation without an external heatsink in most designs.
Typical applications include point-of-load converters feeding FPGAs, DSPs, and microcontrollers from 12V or 24V rails, industrial automation power supplies, telecom equipment, and distributed power bus systems. The wide 5.5V-36V input spans USB supplies through 24V industrial rails, and the output can be set as high as 31V for unusual loads such as LED strings or solenoids.
Design consideration: size the input and output capacitors and inductor per the TI datasheet (SLVS618) equations, and provide a solid thermal copper pour under the PowerPAD to keep the junction temperature below 125C at high loads.
This page synthesizes distributor pricing, drop-in alternatives, practical design notes, and a parameter-by-parameter comparison not found in the manufacturer datasheet alone.
Drop-in alternatives for TPS5450DDAR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with TPS5450DDAR (same form factor and footprint) — differing in Package, Topology, Maximum Output Current, Operating Temperature, Output Voltage Range.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
TPS5450DDA
✅ Drop-In📋 Reference alternative (not in catalog)
TPS5450DDARG4
✅ Drop-In📋 Reference alternative (not in catalog)
TPS5450QDDARQ1
✅ Drop-In✓ In Stock
$1.8 / Unit
View Datasheet →TPS5450MDDAREP
✅ Drop-In📋 Reference alternative (not in catalog)
TPS5430DDAR
✅ Drop-In✓ In Stock
$1.19 / Unit
View Datasheet →TPS54540DDA
✅ Drop-In📋 Reference alternative (not in catalog)
TPS5450DDAR Maximum Ratings & Electrical Characteristics
| Topology | Buck (Step-Down) |
| Input Voltage Range | 5.5 V to 36 V |
| Output Voltage Range | 1.221 V to 31 V (adjustable) |
| Maximum Output Current | 5 A |
| Switching Frequency | 500 kHz (fixed) |
| Number of Outputs | 1 |
| Control Method | Voltage-mode PWM, internally compensated |
| Integrated MOSFET | Low-resistance high-side N-channel |
| Typical Efficiency | > 90 percent |
| Protection Features | Cycle-by-cycle overcurrent, thermal shutdown, programmable soft-start |
| Enable Pin | Yes (ENA) |
| Operating Temperature | -40C to +125C |
| Package | HSOIC PowerPAD (DDA), 8 pins, 3.90 mm width |
| Mounting Type | Surface Mount |
| Family | SWIFT (Step-Down Converter with Integrated FET) |
TPS5450DDAR Pin Configuration
| Pin 1 | BOOT — Bootstrap capacitor connection for high-side gate drive |
| Pin 2 | NC — Not connected (per datasheet) |
| Pin 3 | NC — Not connected (per datasheet) |
| Pin 4 | GND — Ground reference |
| Pin 5 | VSENSE — Feedback voltage sense input for output regulation |
| Pin 6 | ENA — Enable input, active high |
| Pin 7 | SS/TR — Soft-start / tracking programming pin |
| Pin 8 | VIN — Input supply voltage (5.5 V to 36 V) |
Typical Applications
TPS5450DDAR is suitable for 6 applications: FPGA / DSP Point-of-Load Power, Industrial Automation Power Supplies, Telecom and Networking Equipment, 12V/24V Distributed Bus Systems, Motor Drive Logic and Control Supplies, Test and Measurement Instrumentation.
FPGA / DSP Point-of-Load Power
The TPS5450DDAR is a strong fit for FPGA, DSP, and microcontroller point-of-load rails because its 5A continuous output covers the core and I/O current demand of mid-range devices, while the 5.5V-36V input tolerates 12V and 24V intermediate buses directly without an extra pre-regulation stage. The fixed 500kHz switching frequency allows a compact external inductor and predictable output ripple for core rails that tolerate only a few tens of millivolts of noise. Placed on the board between the intermediate bus and the FPGA core pin, the adjustable VSENSE divider sets outputs down to 1.221V with 1 percent feedback accuracy. The SS/TR soft-start pin controls inrush so backplanes do not sag during power-up, and the ENA pin supports rail sequencing required by multi-rail processors.
Recommended
Industrial Automation Power Supplies
Industrial 24V control systems benefit directly from the TPS5450DDAR's 36V maximum input, which provides headroom above nominal 24V rails including tolerance for line transients. The 5A capability drives motors-adjacent logic, sensors, relays, and communication modules from one converter, consolidating the BOM. Cycle-by-cycle overcurrent protection survives shorted loads on the factory floor, and thermal shutdown protects the device inside sealed cabinets with limited airflow. Estimated: at VIN=24V, VOUT=5V, 3A load, roughly 90 percent efficiency yields about 1.7W dissipation, manageable with a standard PowerPAD copper pour. The wide -40C to +125C operating range suits unconditioned cabinets, and the internally compensated voltage-mode control shortens qualification time when scaling one design across multiple product variants.
Recommended
Telecom and Networking Equipment
Telecom boards running from -48V-derived or 24V intermediate buses use the TPS5450DDAR to generate 3.3V, 5V, and 12V housekeeping and line-card rails at up to 5A. The fixed 500kHz frequency simplifies EMI filter design to meet conducted emissions requirements in rack equipment, and the integrated high-side MOSFET reduces component count where board area is at a premium. Efficiency above 90 percent lowers rack-level heat dissipation and fan requirements, an ongoing operating-cost concern in data and telecom closets. The ENA pin and programmable soft-start via SS/TR allow controlled startup sequencing on hot-swap-adjacent supplies, while cycle-by-cycle current limiting prevents downstream faults from propagating into the backplane bus.
Recommended
12V/24V Distributed Bus Systems
In distributed power architectures where a 12V or 24V intermediate bus feeds multiple point-of-load converters, the TPS5450DDAR serves as the local regulator converting bus voltage down to system rails at up to 5A. Its wide 5.5V-36V input means one part number covers both 12V and 24V bus variants, reducing inventory and design effort. The 31V maximum output even supports niche loads such as LED strings or solenoid drivers fed directly from the bus. Efficiency exceeding 90 percent minimizes bus loading and voltage droop on longer harnesses, and the fixed 500kHz switching keeps input filter capacitors small. The PowerPAD package maintains thermal margin at full load without heatsinks in most airflow conditions.
Recommended
Motor Drive Logic and Control Supplies
Motor drive systems need clean, protected logic rails (5V, 3.3V) for microcontrollers, gate-driver logic, and encoders, separated from the noisy power stage. The TPS5450DDAR converts the drive's 12V or 24V bus into these logic rails at up to 5A, and its cycle-by-cycle overcurrent and thermal shutdown provide fault containment when power-stage transients couple into the logic supply. The 500kHz fixed frequency keeps switching harmonics away from sensitive encoder and communication signals, while the SS/TR pin staggers logic-rail startup relative to gate-driver supplies - important for preventing uncontrolled motor motion at power-up. The wide 36V input also tolerates regenerative bus pumping on decelerating loads.
Recommended
Test and Measurement Instrumentation
Bench instruments, data acquisition systems, and industrial measurement nodes use the TPS5450DDAR to generate analog and digital rails from a 12V or 24V input adapter or backplane. The adjustable output down to 1.221V supports modern low-voltage ADC and FPGA supplies, while the fixed 500kHz switching frequency and small external components fit inside compact handheld enclosures. Tight voltage regulation from the internal error amplifier keeps reference-bias rails stable across line and load changes. The enable pin allows the measurement front end to be powered down between readings, reducing average power in battery-buffered instruments, and the 5A rating covers higher-current display and communication subsystems on the same rail.
Recommended
Recommended Products Summary
Engineering reference data for TPS5450DDAR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | TPS5450DDA | TPS5450QDDARQ1 | TPS5430DDAR | TPS54540DDA |
|---|---|---|---|---|---|
| Package | HSOIC-8 PowerPAD (DDA) | HSOIC-8 PowerPAD (DDA) - same | HSOIC-8 PowerPAD (DDA) - same | HSOIC-8 PowerPAD (DDA) - same | HSOIC-8 PowerPAD (DDA) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Maximum Output Current | 5 A | 5 A | 5 A | 3 A | 3.5 A |
| Input Voltage Range | 5.5 V to 36 V | 5.5 V to 36 V | 5.5 V to 36 V | 5.5 V to 36 V | 4.5 V to 42 V |
| Switching Frequency | 500 kHz | 500 kHz | 500 kHz | 500 kHz | 2.2 MHz (TPS54540 family fixed frequency per TI comparison listings) |
| Automotive / Enhanced Grade | No (standard industrial) | No | Yes (AEC-Q100 Q1) | No | No (Q1 version available separately) |
| Minimum Output Voltage | 1.221 V | 1.221 V | 1.221 V | 1.221 V | 0.8 V |
| Lifecycle Status | Active | Active | Active | Active | Active |
Key Differentiators
- Full 5A output at up to 36V input in an 8-pin footprint (vs TPS5430DDAR)
- Integrated high-side N-channel MOSFET reduces BOM (vs Controller-based solutions (LM5117))
- Direct automotive path without redesign (vs TPS5450QDDARQ1)
- Trade-off: no output discharge or wide-frequency selection (vs TPS54540DDA)
Design Notes
The PowerPAD is not optional. Estimated: at VIN=24V, VOUT=5V, 5A load with ~90 percent efficiency, device dissipation approaches 3.3W; with the DDA package theta_JA strongly dependent on copper area, a minimum of 4-6 square centimeters of ground copper pour with an array of thermal vias under the pad is required to hold junction temperature below 125C. Refer to the TI datasheet (SLVS618) PowerPAD section for the thermal layout example, and measure case temperature at full load during validation.
Keep the BOOT capacitor (typically 0.01uF-0.1uF per the datasheet formula) as close as possible to pins 1 and 8, and route the VIN loop (input caps to VIN/GND) with minimum area to contain the high di/dt switching current. Place the VSENSE divider near pin 5 and route the feedback trace away from the switch node and inductor to prevent regulation errors. Use a single-point ground connection between the PowerPAD pour and the signal ground for the divider and ENA networks.
Three frequent mistakes with the TPS5450: (1) leaving the PowerPAD unconnected, causing immediate thermal shutdown at load; (2) undersizing the inductor saturation current - select an inductor with Isat above the cycle-by-cycle current limit, not just the 5A operating current; (3) omitting or mis-sizing the SS/TR capacitor, producing uncontrolled output overshoot at startup. Also verify the ENA pin is not left floating in noise environments; tie it to VIN through a divider if the rail must always run.
The fixed 500kHz switching frequency places fundamental harmonics near the 500kHz-1.5MHz band; if the design must pass conducted emissions, budget a pi-filter (ferrite bead plus bulk electrolytic and ceramic) on the input. Snubberless operation is typical per the TI application examples, but on long wire-harness inputs add an electrolytic damping capacitor at the connector to suppress cable-ring resonance interacting with the 500kHz edge rate.
Compliance Information
RoHS compliant and lead-free per TI DDA package ordering information; TPS5450DDARG4 is the explicit lead-free ordering variant. Formal REACH and conflict-minerals declarations should be downloaded from the TI product quality page. The AEC-Q100 qualified counterpart is TPS5450QDDARQ1.
