Texas Instruments TPS3828-50DBVT

Overview

TPS3828-50DBVT from Texas Instruments is a 5V-supply voltage supervisor IC with open-drain active-low reset output, integrated watchdog timer (1.6 s timeout), manual reset input, and 200 ms reset delay. It monitors VDD for brownout detection, asserts RESET when VDD falls below 4.46–4.64 V, and supports microcontroller-based systems requiring fail-safe power-up sequencing and runtime fault recovery.

For engineers reviewing the TPS3828-50DBVT datasheet, TPS3828-50DBVT pinout, TPS3828-50DBVT application, or TPS3828-50DBVT equivalent, key selection criteria include its open-drain RESET output for wired-OR configuration, fixed 5V threshold with 50 mV hysteresis, −40°C to 85°C operation, 15 µA supply current, and watchdog timer compatibility with MSP430 and similar low-power MCUs.

Technical Context

The TPS3828-50DBVT implements a precision bandgap-based voltage reference and comparator architecture to detect VDD excursions below its nominal 4.55 V threshold. Its internal watchdog timer requires periodic WDI falling edges to prevent timeout-induced reset assertion, with a guaranteed 0.9–2.5 s window. The device uses an internal pullup resistor (90 kΩ) on MR and features input capacitance ≤5 pF at MR/WDI pins.

Unlike push-pull variants (e.g., TPS3823), the TPS3828-50DBVT's open-drain RESET output enables direct connection to shared reset buses without external components. Its 200 ms power-on reset delay begins only after VDD exceeds VIT− + VHYS, ensuring stable power rail establishment before system release.

Key Specifications

Pinout & Package

TPS3828-50DBVT is housed in a 5-pin SOT-23 (DBV) package measuring 2.90 mm × 1.60 mm, optimized for space-constrained PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with TPS3823-50DBVT and TPS3828-33DBVT, the TPS3828-50DBVT uniquely combines 5 V threshold accuracy, open-drain flexibility, and watchdog timer functionality in a single 5-pin SOT-23 footprint-enabling compact, robust reset management where bus sharing or mixed-voltage interfaces are required.

Availability

TPS3828-50DBVT is available at Aetrix Electronics and suitable for industrial automation, wireless sensor networks, and embedded computing applications requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for TPS3828-50DBVT 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 delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The TPS382x product line delivers highly integrated, low-power voltage supervisors with configurable reset behavior and watchdog timers-designed specifically for reliable power-on initialization and runtime fault recovery in microcontroller-based systems.

FAQ

What is the exact reset threshold voltage range for TPS3828-50DBVT?

The TPS3828-50DBVT has a negative-going input threshold voltage (V_IT−) of 4.46 V (min), 4.55 V (typ), and 4.64 V (max) over the −40°C to 85°C operating temperature range. This fixed threshold is factory-trimmed and requires no external components, making TPS3828-50DBVT ideal for precise 5 V rail supervision without calibration.

Does TPS3828-50DBVT require an external pullup resistor on the RESET pin?

Yes, TPS3828-50DBVT features an open-drain RESET output and requires an external pullup resistor to establish a defined logic-high state when inactive. Typical values range from 4.7 kΩ to 10 kΩ to 3.3 V or 5 V, depending on bus loading and rise-time requirements. This design enables wired-OR reset architectures not possible with push-pull variants like TPS3823-50DBVT.

How does the watchdog timer in TPS3828-50DBVT function during normal operation?

The TPS3828-50DBVT watchdog timer requires a falling edge on the WDI pin at least once every 0.9–2.5 seconds. If no edge occurs within that window, RESET asserts for 120–300 ms. During normal operation, the MCU must toggle WDI regularly-typically via GPIO-to prevent spurious resets. The timer clears on each valid falling edge and restarts independently of VDD status.

Can TPS3828-50DBVT be used with a 3.3 V microcontroller I/O pin for manual reset control?

Yes, TPS3828-50DBVT's MR pin accepts logic-level inputs compatible with 3.3 V CMOS: VIH ≥ 0.7 × VDD and VIL ≤ 0.3 × VDD. With VDD = 5 V, this means MR recognizes ≥3.5 V as high and ≤1.5 V as low. A 3.3 V MCU GPIO can directly drive MR low for reset initiation, leveraging the internal 90 kΩ pullup to ensure proper release.

What is the maximum recommended capacitive load on the RESET pin of TPS3828-50DBVT?

The TPS3828-50DBVT datasheet specifies a maximum output short-circuit current (I_OS) of −800 µA for the open-drain RESET pin. To maintain rise time <1 µs with typical 3.3 V pullup, total bus capacitance should remain ≤100 pF. For heavier loads, increase pullup strength or add a buffer; exceeding this limit risks delayed reset deassertion and unreliable system startup.