Texas Instruments TPS3825-33DBVTG4

Overview

TPS3825-33DBVTG4 from Texas Instruments is a 3.3V fixed-threshold voltage supervisor IC with active-low and active-high reset outputs, manual reset input (MR), watchdog timer input (WDI), 200ms reset delay, and 15μA typical supply current in a 5-pin SOT-23 package. It monitors microcontroller supply rails and ensures reliable power-on initialization and fault recovery in embedded systems.

For engineers reviewing the TPS3825-33DBVTG4 datasheet, TPS3825-33DBVTG4 pinout, TPS3825-33DBVTG4 application, or TPS3825-33DBVTG4 equivalent, key selection criteria include its dual-reset-output logic, 2.93V nominal threshold with ±70mV hysteresis, 200ms delay timing, push-pull output drive capability, and compatibility with 3.3V DSP/microcontroller reset interfaces.

Technical Context

The TPS3825-33DBVTG4 implements a precision bandgap-based voltage reference to compare VDD against a fixed 2.93V threshold (VIT−), with built-in 50mV hysteresis (VHYS) to prevent chatter during brownout conditions. Its internal timer initiates a 200ms delay after VDD exceeds VIT− + VHYS before releasing RESET.

It integrates dual-output logic: active-low RESET (push-pull) and active-high RESET (push-pull), both asserted simultaneously on under-voltage or watchdog timeout events. The WDI input requires periodic falling edges to prevent timeout; MR forces immediate reset regardless of VDD or watchdog state.

Key Specifications

Pinout & Package

TPS3825-33DBVTG4 uses a 5-pin SOT-23 (DBV) package, 2.90 mm × 1.60 mm body size, with gull-wing leads optimized for automated assembly and thermal performance (RθJA = 185°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3825-33DBVTG4, TPS3824-33DBVT offers identical electrical behavior without the G4 suffix, while MAX6326–MAX6328 require board-level redesign for pull-up networks and provide less robust watchdog coverage due to shorter timeout.

Availability

TPS3825-33DBVTG4 is available at Aetrix Electronics and suitable for industrial PLCs, wireless sensor nodes, notebook platforms, and microcontroller-based embedded systems requiring stable component supply and long-term lifecycle assurance.

Supply support for TPS3825-33DBVTG4 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 across industrial, automotive, and communications markets.

The TPS382x product line was designed specifically for reliable power-on reset generation and real-time system supervision in DSP and microcontroller-based applications, emphasizing low power, small footprint, and deterministic timing.

FAQ

What is the exact reset threshold voltage of the TPS3825-33DBVTG4?

The TPS3825-33DBVTG4 has a nominal negative-going input threshold voltage (VIT−) of 2.93 V, with a guaranteed range of 2.86 V to 3.00 V over −40°C to 85°C. This value is factory-trimmed and fixed-no external resistors are needed for 3.3V rail supervision. The device also provides 50 mV of hysteresis to ensure noise immunity during supply transients.

Does the TPS3825-33DBVTG4 support both active-low and active-high reset outputs simultaneously?

Yes, the TPS3825-33DBVTG4 provides two independent reset outputs: an active-low RESET (Pin 1) and an active-high RESET (Pin 3). Both outputs share identical timing behavior-including 200ms delay and synchronous assertion during under-voltage or watchdog timeout-and are implemented as push-pull drivers, eliminating the need for external pull-up resistors.

How does the watchdog timer in the TPS3825-33DBVTG4 operate, and what is its timeout period?

The TPS3825-33DBVTG4 watchdog timer triggers a reset if the WDI input remains static (high or low) for longer than 1.6 seconds. A falling edge on WDI clears the timer. If WDI is left unconnected, the device generates internal pulses to prevent spurious timeouts. The 1.6s timeout is factory-fixed and requires no external components-enabling simple, robust firmware hang detection.

Can the manual reset (MR) pin override the watchdog and voltage supervision functions in the TPS3825-33DBVTG4?

Yes, the MR pin on the TPS3825-33DBVTG4 is asynchronous and unconditional: pulling MR low forces immediate assertion of both RESET and RESET outputs, regardless of VDD level or watchdog timer state. The reset remains active for the full 200ms delay after MR returns high, ensuring consistent system behavior during field service or debug operations.

What package and pin configuration does the TPS3825-33DBVTG4 use, and are there any layout considerations?

The TPS3825-33DBVTG4 uses a 5-pin SOT-23 (DBV) package with 2.90 mm × 1.60 mm body size. Pin 1 is RESET (active-low), Pin 2 is GND, Pin 3 is WDI (input) / RESET (active-high), Pin 4 is MR (input), and Pin 5 is VDD. A 0.1 µF ceramic bypass capacitor must be placed close to VDD–GND to stabilize the internal reference and suppress supply noise affecting threshold accuracy.