Texas Instruments TPS3306-15QDRQ1

Overview

TPS3306-15QDRQ1 from Texas Instruments is an automotive-grade dual supervisory circuit for DSP and processor-based systems, monitoring 3.3 V and 1.5 V supply rails with threshold voltages of 2.93 V and 1.4 V respectively, featuring a 100-ms power-on reset delay, 0.8-s watchdog time-out, and open-drain RESET/PFO outputs. It operates across −40°C to 125°C and draws only 15 µA typical supply current.

For engineers reviewing the TPS3306-15QDRQ1 datasheet, TPS3306-15QDRQ1 pinout, TPS3306-15QDRQ1 application, or TPS3306-15QDRQ1 equivalent, key selection considerations include dual-voltage supervision accuracy, watchdog timeout stability over temperature, reset assertion behavior below 1.1 V VDD, and SOIC-8 compatibility in automotive control modules requiring AEC-Q100 qualification.

Technical Context

The TPS3306-15QDRQ1 integrates two independent voltage comparators with fixed thresholds (2.93 V on SENSE1, 1.4 V on SENSE2), a 100-ms reset delay timer triggered after both sense inputs exceed their thresholds, and a watchdog circuit retriggered by WDI transitions with 0.8-s nominal timeout. Its internal 1.25-V reference enables configurable PFI monitoring via external resistor dividers.

RESET asserts low when either SENSE1 or SENSE2 falls below its respective threshold or during power-up until VDD ≥ 1.1 V; PFO provides separate open-drain power-fail indication with 10-mV hysteresis. All outputs are open-drain, requiring external pull-ups, and the device supports operation from 2.7 V to 6 V supply.

Key Specifications

Pinout & Package

TPS3306-15QDRQ1 is housed in an 8-pin SOIC (D) package with 1.27-mm pitch, 3.9-mm body width, and 1.75-mm max height, compliant with JEDEC MS-012AA and RoHS.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3306-15QDRQ1, the TPS3306-18QDRQ1 offers identical architecture but shifts SENSE2 threshold upward for 1.8-V cores, whereas TLV809E26DBVR sacrifices dual supervision, watchdog, and PFI to achieve smaller size and lower cost-making it unsuitable for automotive DSP systems requiring comprehensive fault coverage.

Availability

TPS3306-15QDRQ1 is available at Aetrix Electronics and suitable for automotive engine control units, ADAS camera modules, and infotainment head units requiring stable component supply with AEC-Q100 compliance and extended temperature support.

Supply support for TPS3306-15QDRQ1 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 automotive ICs, with decades of experience in high-reliability power management and supervision solutions.

The TPS3306-Q1 product line was designed specifically for automotive DSP and microprocessor systems requiring dual-voltage monitoring, watchdog protection, and power-fail warning in harsh environments.

FAQ

What is the minimum VDD required for TPS3306-15QDRQ1 to assert a valid RESET signal?

The TPS3306-15QDRQ1 defines RESET behavior once VDD reaches 1.1 V. Below this voltage, RESET is undefined; above it, RESET remains active until both SENSE1 and SENSE2 exceed their thresholds (2.93 V and 1.4 V) and the 100-ms internal timer expires. This ensures robust power-on sequencing even during slow-ramp or brownout conditions.

Can the watchdog timer in TPS3306-15QDRQ1 be disabled, and how?

Yes, the watchdog timer in TPS3306-15QDRQ1 is disabled by leaving the WDI pin unconnected or tying it to a high-impedance state. The datasheet confirms that an unconnected WDI causes internal retriggering, effectively disabling timeout functionality. No configuration register or external component is needed to disable it.

How does the PFI input on TPS3306-15QDRQ1 function, and what voltage range can it monitor?

The PFI input on TPS3306-15QDRQ1 compares an external voltage against an internal 1.25-V reference. Using two 1%-tolerance resistors in a divider network, it can monitor any supply voltage above 1.25 V. For example, connecting PFI to a 12-V battery via R1 = 866 kΩ and R2 = 100 kΩ sets VPFI trip at ~12.5 V, enabling customizable low-battery warnings.

Is TPS3306-15QDRQ1 pin-compatible with other devices in the TPS3306-Q1 family?

Yes, all TPS3306-Q1 variants-including TPS3306-15QDRQ1, TPS3306-18QDRQ1, and TPS3306-25QDRQ1-share identical SOIC-8 (D) packaging, pinout, and terminal functions. Only the SENSE2 threshold differs between models (1.4 V, 1.68 V, 2.25 V), allowing direct PCB reuse when adjusting for different core rail voltages.

What is the maximum load current the RESET and PFO outputs of TPS3306-15QDRQ1 can sink?

The RESET and PFO outputs of TPS3306-15QDRQ1 are open-drain and rated for a maximum low-level output current (IOL) of 5 mA each. At 2 mA sink current and 3.3-V supply, VOL is guaranteed ≤ 0.4 V, ensuring clean logic-low signaling into standard CMOS inputs across temperature.