Texas Instruments TPS7B4255DBVR

Overview

TPS7B4255DBVR from Texas Instruments is a 70-mA, 40-V input voltage-tracking LDO regulator in a 5-pin SOT-23 (DBV) package, delivering ±5 mV tracking accuracy, 500 mV max dropout at full load, reverse polarity and reverse current protection, and operation from –40°C to +150°C junction temperature. It powers off-board industrial sensors such as PIR motion detectors and telemetry RTUs with high ratiometric measurement integrity.

For engineers reviewing the TPS7B4255DBVR datasheet, TPS7B4255DBVR pinout, TPS7B4255DBVR application, or TPS7B4255DBVR equivalent, key selection criteria include ultra-tight tracking tolerance (±5 mV), wide 3–40 V input range with –40 V to +45 V absolute max, integrated UVLO (2.6–2.81 V rising threshold), thermal shutdown (175°C), and signal-buffering capability up to 1 kHz for analog sensor interfaces.

Technical Context

The TPS7B4255DBVR implements a precision voltage-tracking architecture where the ADJ/EN pin serves dual function as reference input and enable control - enabling output regulation at 2–30 V while maintaining ≤5 mV deviation across line, load, and temperature. Its error amplifier compares ADJ/EN voltage directly against internal feedback, supporting both fixed-rail and dynamically varying reference inputs.

Protection circuitry includes brick-wall current limiting (75–130 mA), reverse current blocking (<0.25 µA at VIN = 0 V), short-to-supply survival (no damage at VOUT > VIN), and undervoltage lockout with 300 mV hysteresis. The device operates in two functional modes: active tracking (ADJ/EN > 1.65 V) and ultra-low-power shutdown (ADJ/EN < 1 V, IQ ≤ 3 µA).

Key Specifications

Pinout & Package

TPS7B4255DBVR uses a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm, with exposed pad for thermal enhancement. Pin 5 (NC) must be connected to GND for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage-tracking LDO applications.

Compared with TPS7B4250DBVR, the TPS7B4255DBVR provides 40% higher output current and 5 V additional input headroom - critical for industrial telemetry with long cable drops. Against TPS7B8750QDDARQ1, it trades automotive qualification and higher current for smaller footprint and analog signal buffering - making it optimal for space-constrained industrial sensor hubs.

Availability

TPS7B4255DBVR is available at Aetrix Electronics and suitable for condition monitoring sensors, motion detectors, and wired industrial controls requiring stable component supply, extended temperature operation, and robust fault protection.

Supply support for TPS7B4255DBVR 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 industrial-grade reliability validation.

The TPS7B4255DBVR belongs to TI's high-voltage LDO portfolio designed specifically for off-board sensor powering in harsh industrial environments - emphasizing tracking accuracy, cable-fault resilience, and extended temperature operation.

FAQ

What is the maximum input voltage the TPS7B4255DBVR can withstand without damage?

The TPS7B4255DBVR has an absolute maximum input voltage rating of +45 V and can survive –40 V reverse polarity events without damage. This rating enables reliable operation in industrial 24 V systems subject to load dump transients and accidental battery reversal - a key differentiator from standard 36 V LDOs. Operation above 40 V is outside recommended conditions and may affect long-term reliability.

How does the TPS7B4255DBVR achieve ±5 mV tracking accuracy across temperature and load?

The TPS7B4255DBVR achieves ±5 mV tracking accuracy through a precision error amplifier architecture that directly compares the ADJ/EN reference voltage to the regulated output, with trimmed internal gain and offset. This design maintains tight tracking from –40°C to +150°C and across 100 µA–70 mA load currents without external trimming components - enabling accurate ratiometric measurements in condition monitoring sensors without recalibration.

Can the TPS7B4255DBVR be used to buffer analog signals, and what is its bandwidth limit?

Yes, the TPS7B4255DBVR supports analog signal buffering up to 1 kHz with linear phase and gain response, as confirmed in TI's SBVS441 datasheet Figure 8-1 and Figure 8-2. Beyond 1 kHz, phase shift increases and gain rolls off, causing distortion. For proper operation, the ADJ/EN pin must be driven with a source impedance low enough to avoid loading, and the output must be loaded (e.g., with ≥62 Ω) to prevent instability.

What is the purpose of the NC pin (Pin 5) on the TPS7B4255DBVR, and how should it be connected?

Pin 5 of the TPS7B4255DBVR is a no-connect terminal not bonded internally, but TI specifies connecting it to GND to improve thermal performance. Doing so reduces junction-to-ambient thermal resistance (RθJA) by approximately 15°C/W - critical for maintaining safe operation at 70 mA load in enclosed industrial enclosures. Leaving Pin 5 floating degrades thermal dissipation and risks premature thermal shutdown.

Does the TPS7B4255DBVR provide protection against output short-circuit to the input supply (VOUT-to-VIN short)?

Yes, the TPS7B4255DBVR is explicitly designed to survive output short-circuit to the input supply (VOUT-to-VIN short), as documented in Section 7.3.5 of the SBVS441 datasheet. During such faults, reverse current remains below 5 µA and no device damage occurs - a critical feature for off-board sensor wiring where cable chafing or connector faults can cause this failure mode. This protection is enabled by integrated reverse current blocking and brick-wall current limiting.