Texas Instruments TPS3306-20DGK

Overview

TPS3306-20DGK from Texas Instruments is a dual-voltage supervisory IC designed for DSP and processor-based systems requiring independent monitoring of 3.3 V and 2.0 V supply rails. It provides power-on reset with 100 ms delay, watchdog timer with 0.8 s timeout, open-drain RESET and PFO outputs, and operates across –40°C to +85°C in VSSOP-8 package.

For engineers reviewing the TPS3306-20DGK datasheet, TPS3306-20DGK pinout, TPS3306-20DGK application, or TPS3306-20DGK equivalent, key selection criteria include dual-threshold voltage supervision (2.93 V / 1.85 V), low 15 µA supply current, integrated power-fail comparator, watchdog enable/disable via WDI, and compatibility with battery-powered and automotive embedded systems.

Technical Context

The TPS3306-20DGK implements two independent voltage comparators with fixed thresholds (2.93 V on SENSE1, 1.85 V on SENSE2) referenced to internal precision circuitry. Its RESET output remains active low until both sensed voltages exceed their respective thresholds and sustain for ≥100 ms.

A dedicated PFI input compares external voltage against a 1.25 V internal reference, driving an open-drain PFO output; the watchdog timer resets on any WDI edge and times out after 0.8 s if untriggered, asserting RESET for 100 ms. All logic operates down to VDD ≥1.1 V.

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 thermal pad optional, RoHS-compliant NIPDAU finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3306-20D and TPS3823-20DBVR, the TPS3306-20DGK uniquely delivers dual-rail supervision plus PFI/PFO in the smallest footprint, making it optimal for space-constrained DSP modules where both 3.3 V and 2.0 V integrity must be guaranteed simultaneously.

Availability

TPS3306-20DGK is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive infotainment systems, portable medical sensor hubs, and telecom line cards requiring stable component supply with guaranteed long-term manufacturability.

Supply support for TPS3306-20DGK 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 for industrial, automotive, and personal electronics markets.

The TPS3306 family was engineered specifically for dual-voltage supervision in DSP and processor-based systems, addressing the need for coordinated reset sequencing, watchdog safety, and auxiliary supply monitoring in compact, low-power designs.

FAQ

What is the exact SENSE1 and SENSE2 threshold voltage for TPS3306-20DGK?

The TPS3306-20DGK has a nominal SENSE1 threshold of 2.93 V and SENSE2 threshold of 1.85 V, both specified at TA = 25°C and VDD = 2.7 V to 6 V. These values are factory-trimmed and guaranteed over temperature (–40°C to +85°C) with ±3% tolerance per the Electrical Characteristics table in the SLVS290C datasheet.

Can TPS3306-20DGK supervise voltages other than 3.3 V and 2.0 V?

Yes - while TPS3306-20DGK is optimized for 3.3 V/2.0 V pairs, its PFI input accepts any voltage above 1.25 V via external resistor divider to generate power-fail alerts. SENSE1 and SENSE2 thresholds are fixed and not adjustable; for non-standard rail supervision, consider the TPS3307 or TPS3808 families.

How is the watchdog timer enabled or disabled on TPS3306-20DGK?

The watchdog timer in TPS3306-20DGK is enabled by applying periodic edges (rising or falling) to the WDI pin within the 0.8 s timeout window. Leaving WDI unconnected or held statically high/low disables the watchdog function entirely, and RESET will only respond to supply voltage faults.

What package type does TPS3306-20DGK use, and what are its key mechanical dimensions?

TPS3306-20DGK uses the VSSOP-8 (DGK) package: 3.0 mm × 3.0 mm body size, 0.65 mm lead pitch, 1.1 mm maximum height, and optional exposed thermal pad. Pin 1 is located in the top-left corner with a molded index notch, per JEDEC MO-187 standard.

Does TPS3306-20DGK provide reset assertion during power-down events?

Yes - TPS3306-20DGK asserts RESET whenever either SENSE1 or SENSE2 falls below its threshold voltage (2.93 V or 1.85 V), including during power-down. The RESET output remains active low until both inputs rise above threshold and remain stable for the full 100 ms delay period, ensuring clean restart behavior.