Texas Instruments TPS5402DR

Overview

TPS5402DR from Texas Instruments is a monolithic non-synchronous step-down (buck) regulator with integrated 120-mΩ high-side N-channel MOSFET, operating from 3.5 V to 28 V input and delivering up to 1.7-A continuous output current at adjustable 70–120 kHz switching frequency. It implements peak current-mode control with internal slope compensation, pulse-skipping mode for light-load efficiency, and thermal shutdown at 165°C - used in distributed power systems for consumer electronics and industrial supplies.

For engineers reviewing the TPS5402DR datasheet, TPS5402DR pinout, TPS5402DR application, or TPS5402DR equivalent, key selection considerations include its SOIC-8 package, 0.8-V feedback reference accuracy (±3%), programmable soft-start via external capacitor, frequency spread spectrum for EMI reduction, and cycle-by-cycle overcurrent protection with frequency foldback during fault conditions.

Technical Context

The TPS5402DR uses constant-frequency peak current-mode control with internal slope compensation to stabilize operation above 50% duty cycle and reduce external compensation complexity. Its error amplifier features 92 µA/V transconductance and supports type-II/III compensation networks via the COMP pin.

Switching frequency is set externally via ROSC pin: grounded for 70 kHz, open for 120 kHz, or resistor-programmed from 50 kHz to 1.1 MHz. Pulse skipping activates below ~300 mA peak inductor current to maintain high efficiency at light loads, while frequency foldback and thermal shutdown provide robust fault protection.

Key Specifications

Pinout & Package

TPS5402DR is housed in an 8-pin SOIC (D) package with 1.27-mm pitch, 1.75-mm max height, and RoHS-compliant NiPdAu lead finish (MSL Level-1). Thermal resistance θ_JA is 116.7°C/W on JEDEC-standard high-K board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar non-synchronous buck regulator applications.

Compared with TPS5402DR, TPS54040DR supports higher input voltage but delivers less current, while LM2678SD-5.0/NOPB offers greater output current at fixed 5 V but lacks programmability and SOIC-8 compatibility - making TPS5402DR optimal for adjustable 1.7-A mid-range buck conversion in space-constrained designs.

Availability

TPS5402DR is available at Aetrix Electronics and suitable for consumer electronics, industrial automation, and automotive infotainment systems requiring stable component supply and long-term production continuity.

Supply support for TPS5402DR 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 decades of expertise in high-reliability power conversion ICs.

The TPS5402DR belongs to TI's SWIFT™ family of integrated DC-DC regulators, designed specifically for compact, efficient, and robust non-synchronous buck conversion in cost-sensitive and thermally constrained applications.

FAQ

What is the maximum output current supported by the TPS5402DR?

The TPS5402DR supports up to 1.7-A continuous output current under typical thermal conditions with adequate PCB copper area. Peak inductor current limit is 2.2–3.1 A (typical 2.5 A), but sustained operation above 1.7 A requires careful thermal design due to SOIC-8 package limitations and 116.7°C/W junction-to-ambient resistance. Derating is recommended above 85°C ambient.

How do I configure the switching frequency of the TPS5402DR?

The TPS5402DR switching frequency is configured via the ROSC pin: connect ROSC to GND for 70 kHz, leave it open for 120 kHz, or use an external resistor (e.g., 85.5 kΩ for 300 kHz) between ROSC and GND. The relationship follows f_SW ≈ 1.167 × 10⁶ / R_OS(kΩ) kHz. No pull-up or pull-down is needed - the pin is internally biased.

Does the TPS5402DR require an external bootstrap diode?

No, the TPS5402DR does not require an external bootstrap diode because it integrates a boot recharge circuit. A 0.1-µF X7R/X5R ceramic capacitor must be placed between BOOT and LX pins to sustain gate drive voltage for the internal high-side MOSFET; the integrated circuit automatically recharges this capacitor each switching cycle.

What protection features are built into the TPS5402DR?

The TPS5402DR includes cycle-by-cycle overcurrent protection, thermal shutdown at 165°C, input undervoltage lockout (UVLO) at 3.5 V with 200-mV hysteresis, and overvoltage transient protection (OVTP) that disables the high-side MOSFET if VSENSE exceeds 109% of 0.8 V. Frequency foldback further limits inductor current during overload or short-circuit events.

Can the TPS5402DR operate with a 3.3-V output?

Yes, the TPS5402DR can regulate a 3.3-V output using a resistive divider from VOUT to GND connected to the VSENSE pin. With a 0.8-V internal reference, a standard R1 = 100 kΩ (top) and R2 = 31.6 kΩ (bottom) divider achieves 3.3 V (VOUT = 0.8 × (1 + R1/R2)). Compensation components on the COMP pin must be selected per application requirements to ensure stability.