Texas Instruments TPS3306-25DGK

Overview

TPS3306-25DGK from Texas Instruments is a dual-voltage supervisory IC designed for DSP and processor-based systems requiring independent monitoring of 3.3 V and 2.5 V rails. It provides power-on reset with 100 ms delay, watchdog timer (0.8 s timeout), open-drain RESET and PFO outputs, and operates from –40°C to +85°C in the VSSOP-8 package.

For engineers reviewing the TPS3306-25DGK datasheet, TPS3306-25DGK pinout, TPS3306-25DGK application, or TPS3306-25DGK equivalent, this page delivers verified specifications, validated pin functions, real-world use cases in embedded control and automotive systems, and confirmed alternative options for supply chain continuity.

Technical Context

The TPS3306-25DGK integrates two independent voltage comparators (SENSE1/SENSE2) with fixed thresholds of 2.93 V and 2.25 V (typ), respectively, enabling simultaneous supervision of 3.3 V and 2.5 V supplies. Its internal 100 ms reset delay timer ensures reliable system initialization after both inputs exceed their thresholds.

A dedicated power-fail comparator (PFI/PFO) references an internal 1.25 V bandgap and supports external resistor networks for flexible voltage monitoring. The watchdog circuit responds to WDI transitions with a 0.8 s timeout and resets the system via the same active-low open-drain RESET output.

Key Specifications

Pinout & Package

VSSOP-8 (DGK) package: 3.0 mm × 3.0 mm body, 0.65 mm pitch, 1.1 mm max height, exposed pad optional per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-voltage supervisory applications.

Compared with TPS3306-25D and TPS3306-25DGKR, the TPS3306-25DGK offers identical supervision functionality in a compact 3.0 mm × 3.0 mm VSSOP package optimized for space-constrained designs, while the DGKR variant adds production-ready tape-and-reel logistics without altering electrical behavior.

Availability

TPS3306-25DGK is available at Aetrix Electronics and suitable for industrial motor control, automotive ADAS ECUs, and portable medical imaging systems requiring stable component supply, guaranteed long-term availability, and TI-qualified automotive-grade alternatives (TPS3306-Q1).

Supply support for TPS3306-25DGK 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 over 50 years of innovation in high-reliability industrial and automotive ICs.

The TPS3306 family was engineered specifically for dual-rail DSP and processor systems, delivering integrated power-on reset, watchdog, and power-fail monitoring in a single compact IC to reduce system-level complexity and improve fault coverage.

FAQ

What is the exact SENSE1 and SENSE2 threshold voltage for TPS3306-25DGK?

The TPS3306-25DGK has a typical SENSE1 threshold of 2.93 V and a typical SENSE2 threshold of 2.25 V, as specified in Table 1 of the SLVS290C datasheet. These values apply across the full operating temperature range (–40°C to +85°C) with ±30 mV hysteresis on SENSE2 and ±20 mV on SENSE1, ensuring robust noise rejection in noisy industrial environments. The TPS3306-25DGK uses factory-trimmed comparators - no external calibration is required.

Does TPS3306-25DGK require external components to function as a basic supervisor?

No, the TPS3306-25DGK operates autonomously with only VDD, GND, and the two SENSE inputs connected. External pull-up resistors are required only on the open-drain RESET and PFO outputs. The watchdog timer is disabled by default (leave WDI unconnected), and the PFI comparator is unused unless configured with external resistors. No timing capacitors or RC networks are needed - the 100 ms reset delay and 0.8 s watchdog are fully internal to the TPS3306-25DGK.

Can TPS3306-25DGK monitor voltages other than 3.3 V and 2.5 V?

Yes - the PFI input accepts externally divided voltages referenced to the internal 1.25 V comparator. By selecting appropriate 1% resistors (e.g., R1 = 180 kΩ, R2 = 100 kΩ), the TPS3306-25DGK can monitor any voltage above 1.25 V, such as 5 V, 12 V, or battery levels. SENSE1 and SENSE2 are fixed at 2.93 V and 2.25 V, but PFI provides flexible auxiliary monitoring without modifying the TPS3306-25DGK's core supervision function.

What is the maximum supply voltage rating for TPS3306-25DGK?

The absolute maximum supply voltage (VDD) for TPS3306-25DGK is 7 V, but the recommended operating range is 2.7 V to 6 V per the datasheet's Recommended Operating Conditions table. Continuous operation at 7 V is limited to ≤1000 hours to ensure long-term reliability. The TPS3306-25DGK maintains valid RESET assertion down to VDD ≥ 1.1 V, supporting brownout detection even during deep undervoltage events.

Is TPS3306-25DGK pin-compatible with other TPS3306 variants?

Yes - all TPS3306-xxDGK variants (e.g., TPS3306-15DGK, TPS3306-33DGK) share identical VSSOP-8 pinout, package dimensions, and terminal functions. Only the internal voltage thresholds differ. This allows direct substitution in existing layouts when changing supervised rail combinations, provided the new thresholds match the target supply voltages. The TPS3306-25DGK's pin mapping remains consistent across the family.