Texas Instruments TPS3110K33DBVR

Overview

TPS3110K33DBVR from Texas Instruments is an ultralow-supply-current voltage supervisor IC with integrated watchdog timer, designed for power-on reset and runtime supervision of microprocessors in battery-constrained systems. It features a fixed 3.3V VDD threshold (±0.75% accuracy), 1.2μA typical supply current, push-pull active-low RESET output, and watchdog timeout of 1.1s (typical). It operates across –40°C to 125°C and monitors both VDD and SENSE inputs.

For engineers reviewing the TPS3110K33DBVR datasheet, TPS3110K33DBVR pinout, TPS3110K33DBVR application, or TPS3110K33DBVR equivalent, key selection criteria include its 3.3V supervision accuracy, sub-2μA quiescent current at VDD < 1.8V, push-pull RESET drive capability, watchdog timer interface via WDI, and SOT-23-6 package compatibility with space-constrained PCB layouts.

Technical Context

The TPS3110K33DBVR implements a dual-comparator architecture: one dedicated to VDD supervision (VIT– = 2.941V, ±0.75%) and another for external voltage monitoring via SENSE (VIT–(S) = 0.551V, ±1.5%). Its internal reset timer provides a 130ms delay after VDD exceeds VIT– + VHYS before deasserting RESET.

Watchdog functionality is triggered by edge transitions on WDI; failure to toggle within 1.1s (typical) forces RESET assertion. The MR input supports manual reset with internal 100kΩ pullup and 5μs propagation delay, enabling system-level fault recovery without external components.

Key Specifications

Pinout & Package

TPS3110K33DBVR is housed in a 6-pin SOT-23 (DBV) package measuring 2.90mm × 2.80mm, optimized for high-density PCB layouts and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3110K33DBVR, TPS3110K33DBVT offers identical performance in tape-and-reel format for volume manufacturing, while TPS3823-33DBVR trades watchdog capability for 0.4μA lower quiescent current-making it optimal for static-sensing applications but unsuitable for MCU lockup protection.

Availability

TPS3110K33DBVR is available at Aetrix Electronics and suitable for battery-powered wireless sensors, automotive body electronics, and industrial PLC modules requiring stable component supply with guaranteed long-term availability.

Supply support for TPS3110K33DBVR 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 precision analog ICs.

The TPS31xx family was engineered specifically for ultra-low-power voltage supervision in DSP and microcontroller systems, emphasizing sub-2μA operation, high threshold accuracy, and integrated watchdog functionality for mission-critical embedded applications.

FAQ

What is the exact VDD threshold voltage for TPS3110K33DBVR and how tightly is it specified?

The TPS3110K33DBVR has a nominal VDD threshold voltage of 2.941V at 25°C, with a maximum deviation of ±0.75% across temperature and process variations. This corresponds to a guaranteed range of 2.919V to 2.963V at 25°C and 2.823V to 3.058V over –40°C to 125°C. These values are measured per TI's SLVS363H datasheet and ensure deterministic reset behavior in 3.3V systems even under worst-case conditions. The TPS3110K33DBVR uses an internal precision voltage divider to achieve this stability without external calibration.

Does TPS3110K33DBVR require external components to operate as a basic power-on reset supervisor?

No, the TPS3110K33DBVR functions as a complete power-on reset supervisor with only a 0.1μF ceramic bypass capacitor on VDD-no resistors, pullups, or timing components are needed. Its internal 100kΩ MR pullup allows direct switch connection, and the push-pull RESET output drives microcontroller reset pins without external biasing. The TPS3110K33DBVR integrates all supervision logic, timer, and comparator circuitry, making it a drop-in solution for 3.3V rail monitoring in space-constrained designs.

How does the watchdog timer in TPS3110K33DBVR respond to WDI signal transitions?

The TPS3110K33DBVR watchdog timer clears on every rising or falling edge at the WDI pin and triggers RESET if no edge occurs within 1.1s (typical; 0.55s to 1.65s min/max). The timer does not distinguish edge direction-it responds to any valid logic transition. During normal operation, firmware must toggle WDI at least once per timeout period. If the MCU locks up and stops toggling WDI, the TPS3110K33DBVR asserts RESET for the full 130ms delay, ensuring reliable recovery. This behavior is confirmed in Section 7.3.1 and Figure 6-4 of the SLVS363H datasheet.

Can TPS3110K33DBVR monitor a 1.5V core supply while supervising a 3.3V I/O rail?

Yes, the TPS3110K33DBVR simultaneously monitors both rails: VDD (3.3V) and SENSE (via resistor divider). To supervise a 1.5V core, connect SENSE to a voltage divider (e.g., R1=820kΩ, R2=430kΩ) that scales 1.5V down to 0.551V-the internal SENSE comparator threshold. When the core drops below the scaled threshold, RESET asserts regardless of VDD status. This dual-monitoring capability is explicitly supported in the TPS3110K33DBVR functional block diagram (Figure 7-3) and typical application schematic (Figure 7-5), enabling single-chip supervision of heterogeneous power domains.

What is the minimum VDD voltage required for TPS3110K33DBVR to assert RESET during power-up?

The TPS3110K33DBVR asserts RESET as soon as VDD exceeds 0.4V, per the "RESET Defined With Input Voltages as Low as 0.4V" feature in the datasheet. This early assertion ensures microcontrollers remain held in reset even during very slow or weak power ramp-ups-critical for battery-powered devices with high-impedance sources. Once VDD rises above the 2.941V threshold plus hysteresis, the internal 130ms timer begins; RESET deasserts only after this delay completes. This behavior is validated in Section 3 (Description) and Figure 6-4 of the SLVS363H datasheet for TPS3110K33DBVR.