Texas Instruments TL7733BIDG4

Overview

TL7733BIDG4 from Texas Instruments is a precision supply-voltage supervisor IC designed as a reset controller for microprocessor and microcontroller systems. It monitors the SENSE input for undervoltage conditions, provides true and complement reset outputs (RESET and RESET), features an externally adjustable reset pulse duration via CT capacitor, and maintains defined reset behavior down to VCC ≥ 1 V. It is used in industrial embedded systems requiring reliable power-on and brownout reset signaling.

For engineers reviewing the TL7733BIDG4 datasheet, TL7733BIDG4 pinout, TL7733BIDG4 application, or TL7733BIDG4 equivalent, this page delivers verified technical context, exact pin functions, real-world timing and threshold specifications, thermal and electrical performance data, and validated alternative options for voltage supervision in temperature-critical designs.

Technical Context

The TL7733BIDG4 implements a precision bandgap-based voltage reference with temperature compensation to achieve stable trip-point accuracy across –40°C to 85°C. Its internal comparator continuously compares the SENSE input against a fixed 3.08 V nominal threshold (VIT–), with 10 mV hysteresis to prevent chatter during slow voltage transitions.

Reset assertion is triggered when SENSE falls below VIT–; deassertion occurs after SENSE rises above VIT+ and a user-defined delay set by the external CT capacitor (td ≈ 2.6 × 10⁴ × CT). The RESIN pin enables manual reset override, forcing RESET high and RESET low regardless of SENSE state.

Key Specifications

Pinout & Package

TL7733BIDG4 is housed in an SOIC-8 (D) package measuring 4.90 mm × 3.91 mm, with standard 1.27 mm lead pitch and RoHS-compliant NiPdAu lead finish. It is rated MSL Level-1 (unlimited floor life at ≤30°C/60% RH).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL7733BIDG4, TPS3808G33DBVR offers superior power efficiency but sacrifices timing flexibility, while MAX6326UT33D3+ simplifies layout with push-pull drive yet limits voltage range and removes complement output capability-making TL7733BIDG4 uniquely balanced for industrial 3.3 V supervision with design adaptability.

Availability

TL7733BIDG4 is available at Aetrix Electronics and suitable for industrial PLC control, factory automation sensors, building management systems, and industrial gateways requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TL7733BIDG4 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 delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and communications markets.

The TL77xxB family was engineered specifically for robust, precision voltage supervision in microprocessor-based systems where reliable power-on and brownout reset behavior is mission-critical under varying thermal and electrical conditions.

FAQ

What is the exact voltage threshold and hysteresis of TL7733BIDG4?

The TL7733BIDG4 has a nominal negative-going input threshold (VIT–) of 3.08 V, specified from 3.03 V to 3.16 V over –40°C to +85°C. Its hysteresis (VHYS) is 10 mV, ensuring stable reset release without chatter during slow-ramping or noisy supply conditions. This threshold is optimized for monitoring standard 3.3 V rails, and the hysteresis is fixed-not adjustable-by internal design.

How does the CT pin on TL7733BIDG4 determine reset pulse duration?

The CT pin on TL7733BIDG4 connects to an external capacitor that sets the reset pulse width using td ≈ 2.6 × 10⁴ × CT (with CT in farads and td in seconds). For example, a 0.1 µF capacitor yields ~2.6 ms. The internal current source charges CT until it reaches a reference voltage (~1.8 V), then discharges partially to ~0.6 V. This timing mechanism ensures the reset outputs remain active long enough for complete processor initialization after voltage recovery.

Can TL7733BIDG4 monitor voltages other than 3.3 V?

Yes - TL7733BIDG4 monitors any voltage applied to its SENSE pin, but its internal 3.08 V threshold is fixed and optimized for 3.3 V rails. To supervise higher or lower rails (e.g., 5 V or 1.8 V), use a resistor divider between the rail and SENSE to scale the input. Ensure the divider's Thevenin resistance stays below 10 kΩ to avoid threshold shift, and verify accuracy over temperature and tolerance stack-up in final design.

Why does TL7733BIDG4 require external pull-up/pull-down resistors on RESET and RESET?

TL7733BIDG4 uses open-collector outputs on both RESET and RESET pins, meaning they can only sink current - not source it. External pull-up (for RESET) and pull-down (for RESET) resistors establish defined logic levels when outputs are inactive. TI recommends 10 kΩ for both to ensure fast edge rates, prevent waveform plateauing, and maintain compatibility with common MCU reset input thresholds, especially under capacitive loading.

Is TL7733BIDG4 pin-compatible with other TL77xxB variants like TL7705B or TL7702B?

Yes - TL7733BIDG4 shares identical SOIC-8 pinout, function mapping, and electrical interface with TL7702B and TL7705B. The only differences are their fixed voltage thresholds: TL7702B (2.53 V), TL7705B (4.55 V), and TL7733B (3.08 V). This pin-for-pin compatibility allows drop-in replacement across 2.5 V, 3.3 V, and 5 V supervision needs without PCB changes, provided the operating temperature range (–40°C to +85°C) and supply voltage (3.6–18 V) remain within spec.