Texas Instruments TPS3828-33DBVTG4

Overview

TPS3828-33DBVTG4 from Texas Instruments is a 3.3V supply voltage supervisor IC with open-drain active-low reset output, integrated watchdog timer (1.6s timeout), manual reset input, and 200ms reset delay. It operates from 1.1V to 5.5V, draws 15μA typical supply current, and is qualified for −40°C to 85°C industrial temperature range. It is used in microcontroller-based systems requiring reliable power-on initialization and fault recovery.

For engineers reviewing the TPS3828-33DBVTG4 datasheet, TPS3828-33DBVTG4 pinout, TPS3828-33DBVTG4 application, or TPS3828-33DBVTG4 equivalent, key selection criteria include its open-drain RESET output compatibility with wired-OR logic, fixed 2.93V threshold with 50mV hysteresis, watchdog timer behavior under WDI floating conditions, and SOT-23-5 package footprint constraints.

Technical Context

The TPS3828-33DBVTG4 implements a precision voltage supervision circuit with internal 2.93V threshold (V_IT−) and 50mV hysteresis, enabling stable detection of 3.3V rail undervoltage events. Its watchdog timer triggers reset if WDI remains static beyond 1.6s, and clears on falling edge or RESET assertion.

It features a manual reset input (MR) that forces active-low RESET regardless of VDD level, with internal 90kΩ pullup. The open-drain RESET output supports flexible interface configurations including level translation and multi-source reset arbitration, unlike push-pull variants in the same family.

Key Specifications

Pinout & Package

TPS3828-33DBVTG4 is housed in a 5-pin SOT-23 (DBV) package with nominal body size 2.90mm × 1.60mm and standard lead pitch. The package is RoHS-compliant and optimized for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3823-33DBVT and MAX6326UT33+T, the TPS3828-33DBVTG4 uniquely combines open-drain output flexibility with integrated watchdog functionality-enabling both robust power sequencing and runtime firmware supervision in a single 5-pin SOT-23 device.

Availability

TPS3828-33DBVTG4 is available at Aetrix Electronics and suitable for microcontroller-based embedded systems, industrial PLCs, battery-powered sensor nodes, and notebook platform power management requiring stable component supply and long-term lifecycle support.

Supply support for TPS3828-33DBVTG4 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 company delivering analog and embedded processing solutions, with leadership in power management, signal chain, and microcontrollers.

The TPS382x product line delivers compact, low-power voltage supervisors with configurable reset outputs and watchdog timers, designed specifically for reliable power-on initialization and runtime fault detection in DSP, MCU, and processor-based systems.

FAQ

What is the exact reset threshold voltage of the TPS3828-33DBVTG4?

The TPS3828-33DBVTG4 has a negative-going input threshold voltage (V_IT−) of 2.86V minimum, 2.93V typical, and 3.00V maximum across −40°C to 85°C. This 2.93V nominal value is factory-trimmed to target 3.3V supply rails with ±2.4% tolerance, and includes 50mV hysteresis to prevent oscillation during rail transitions. The threshold is set by an internal voltage divider and requires no external components.

Does the TPS3828-33DBVTG4 require an external pullup resistor on the RESET pin?

Yes, the TPS3828-33DBVTG4 features an open-drain RESET output and requires an external pullup resistor to define the inactive (high) state voltage level. Typical values range from 10kΩ to 100kΩ depending on bus capacitance and rise-time requirements. The pullup may connect to VDD, another logic rail, or a dedicated reset supervisor voltage - enabling level translation and wired-OR reset bus configurations not possible with push-pull outputs.

How does the watchdog timer behave if the WDI pin is left unconnected?

When the WDI pin is left floating, the TPS3828-33DBVTG4 internally generates pulses to prevent unintended watchdog timeout. This default behavior avoids false resets in systems where watchdog functionality is unused. If continuous WDI activity is required even during normal operation, the pin must be actively driven; if floating behavior is undesirable, a 1kΩ resistor to ground ensures detection of a defined low state and disables internal pulse generation.

Can the TPS3828-33DBVTG4 be used with a 5V supply rail?

Yes, the TPS3828-33DBVTG4 operates with supply voltages from 1.1V to 5.5V and can monitor any rail within that range. However, its fixed 2.93V threshold is optimized for 3.3V systems. When powered from 5V, it still supervises the VDD pin - meaning it monitors the 5V rail only if VDD is connected to that rail. To supervise a 5V rail, use the TPS3828-50 variant instead, which has a 4.55V threshold. The "-33" suffix explicitly denotes 3.3V supervision capability.

What is the function of the MR pin on the TPS3828-33DBVTG4?

The MR (manual reset) pin on the TPS3828-33DBVTG4 is an active-low input that forces the RESET output low regardless of VDD level or watchdog state. It features an internal 90kΩ pullup resistor, so it defaults to inactive (high) when unconnected. Pulling MR ≤0.3×VDD asserts RESET for the full 200ms delay period, then releases it - enabling hardware-initiated resets via pushbuttons, FPGA outputs, or other control logic without affecting power rail monitoring.