Texas Instruments TPS3307-33DR

Overview

TPS3307-33DR from Texas Instruments is a triple-voltage supervisor IC designed for power-on reset and supply monitoring in DSP, microcontroller, and processor-based systems. It monitors 5V (SENSE1), 3.3V (SENSE2), and an adjustable voltage ≥1.25V (SENSE3) with fixed 200ms reset delay, 40µA supply current, and operation from –40°C to +85°C in SOIC-8 package.

For engineers reviewing the TPS3307-33DR datasheet, TPS3307-33DR pinout, TPS3307-33DR application, or TPS3307-33DR equivalent, key selection considerations include triple-supply threshold accuracy (4.55V/2.93V/1.25V), dual active-high/active-low RESET outputs, manual reset (MR) support, and compatibility with industrial, automotive, and portable equipment requiring reliable multi-rail power sequencing.

Technical Context

The TPS3307-33DR integrates three independent voltage comparators with temperature-compensated 1.25V reference, enabling precise supervision of nominal 5V and 3.3V rails plus one user-defined rail. Its internal 200ms power-on reset timer eliminates external capacitor dependency.

RESET assertion occurs when any SENSE input falls below its hysteresis-equipped threshold (e.g., VIT– = 4.46V for SENSE1), while MR provides asynchronous reset control. The device guarantees defined RESET output down to VDD ≥1.1V and supports bidirectional logic-level compatibility via separate RESET (active-low) and RESET (active-high) terminals.

Key Specifications

Pinout & Package

TPS3307-33DR is housed in an 8-pin SOIC (D) package, 3.9mm × 4.9mm, 1.75mm max height, RoHS-compliant with NiPdAu lead finish and MSL Level-1 rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3307-33DGN, the TPS3307-33DR offers identical supervision performance in a standard SOIC-8 package optimized for automated assembly and thermal robustness, while the MAX6816TPA+ provides lower power but cannot replace the triple-monitoring capability without significant redesign.

Availability

TPS3307-33DR is available at Aetrix Electronics and suitable for industrial programmable controls, automotive body electronics, and portable medical diagnostics requiring stable component supply and long-term production continuity.

Supply support for TPS3307-33DR 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 experience in high-reliability industrial and automotive ICs.

The TPS3307 family was engineered specifically for multi-rail power sequencing in DSP and microprocessor systems, addressing the need for accurate, low-power, and integrated voltage supervision without external timing components.

FAQ

What is the function of the dual RESET outputs on the TPS3307-33DR?

The TPS3307-33DR provides both active-low RESET (pin 5) and active-high RESET (pin 6) to ensure direct compatibility with diverse host devices. The active-low output is open-drain and requires an external pull-up resistor, while the active-high output is push-pull and drives directly to VDD. This dual configuration eliminates level-shifting requirements when interfacing with legacy microcontrollers and modern FPGAs simultaneously in the same design.

Can the TPS3307-33DR monitor a 2.5V supply on SENSE2?

No - the TPS3307-33DR is factory-configured for 5V on SENSE1 and 3.3V on SENSE2, with fixed thresholds of 4.46V–4.64V and 2.86V–3.02V respectively. To supervise a 2.5V rail, use the TPS3307-25DR variant, which specifies SENSE2 threshold at 2.20V–2.32V. Using the TPS3307-33DR for 2.5V would result in undetected brownout conditions due to mismatched trip points.

How does the manual reset (MR) input interact with the automatic reset timing?

The MR input on the TPS3307-33DR is asynchronous and overrides all automatic supervision logic. When MR is pulled low, RESET (pin 5) immediately goes active-low and RESET (pin 6) goes active-high, regardless of SENSE input states. Release of MR initiates the full 200ms reset timeout period before deassertion - identical to the power-on sequence - ensuring deterministic system recovery after manual intervention.

What is the minimum required external component for basic operation of the TPS3307-33DR?

The only mandatory external component for basic operation of the TPS3307-33DR is a 0.1µF ceramic bypass capacitor between VDD (pin 8) and GND (pin 4), placed as close as possible to the device. This capacitor stabilizes the internal reference and prevents false resets during supply transients. No timing capacitor is needed due to the integrated 200ms reset timer.

Is the TPS3307-33DR compatible with 1.8V logic levels on the MR pin?

Yes - the MR input threshold is defined as VIL ≤ 0.3×VDD and VIH ≥ 0.7×VDD, making it fully compatible with 1.8V logic when VDD ≥ 2.57V (since 0.7×2.57V ≈ 1.8V). For guaranteed 1.8V-compatible operation, operate the TPS3307-33DR with VDD ≥ 2.6V and verify MR drive strength meets the –130µA (min) low-level input current requirement per the datasheet.