Texas Instruments TL7702BCDR

Overview

TL7702BCDR from Texas Instruments is a precision supply-voltage supervisor IC designed as a reset controller for microcomputer systems. It monitors the SENSE input for undervoltage conditions, provides true and complement RESET outputs (active-high and active-low), features externally adjustable reset pulse duration via CT pin, and operates across 3.6 V to 18 V supply range with 2.53 V ±25 mV threshold voltage. Used in server power sequencing and industrial microcontroller reset management.

For engineers reviewing the TL7702BCDR datasheet, TL7702BCDR pinout, TL7702BCDR application, or TL7702BCDR equivalent, key selection considerations include its 2.53 V trip point, SOIC-8 package, dual-reset output architecture, temperature-compensated reference, and compatibility with 0°C to 70°C commercial operation.

Technical Context

The TL7702BCDR implements a precision voltage-sense comparator with hysteresis (10 mV) and an internal temperature-compensated 2.53 V reference. Its CT pin connects to an external capacitor that sets reset pulse width via a 26 µA current source (td ≈ 2.6×10⁴ × CT).

It supports both power-on reset initiation (RESET active below VCC ≈ 1 V) and dynamic undervoltage detection at SENSE, with RESIN enabling manual reset override. The REF output delivers a stable 2.53 V reference for external circuitry, requiring a 0.1 µF bypass capacitor.

Key Specifications

Pinout & Package

TL7702BCDR is housed in an 8-pin SOIC (D) package measuring 4.90 mm × 3.91 mm, RoHS-compliant with NiPdAu lead finish and Level-1 MSL rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G33DBVR and MAX6326LT33D3+T, TL7702BCDR uniquely delivers both true/complement reset outputs, a buffered 2.53 V reference, and user-adjustable reset pulse width-making it optimal for industrial microcontroller reset coordination where signal flexibility and design margin matter.

Availability

TL7702BCDR is available at Aetrix Electronics and suitable for industrial PLC control, server power sequencing, factory automation HMI, and network equipment power management requiring stable component supply and long-term production continuity.

Supply support for TL7702BCDR 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 and embedded processing solutions, with over 90 years of innovation in power management, signal chain, and microcontrollers.

The TL77xxB series was developed specifically for robust reset control in microprocessor-based systems, emphasizing precision threshold accuracy, dual-output flexibility, and wide-supply operation in industrial and computing environments.

FAQ

What is the exact voltage threshold and hysteresis of TL7702BCDR?

The TL7702BCDR has a nominal negative-going input threshold voltage (V_IT–) of 2.53 V at 25°C, with a guaranteed range of 2.505 V to 2.555 V. Its hysteresis is 10 mV, meaning the positive-going threshold is approximately 2.54 V. This tight tolerance ensures reliable supervision of 3.3 V supply rails across the full 0°C to 70°C operating range, and the TL7702BCDR maintains this performance without external calibration.

How does the CT pin function in TL7702BCDR, and what capacitor value yields a 2.6 ms reset pulse?

The CT pin on TL7702BCDR connects to an external capacitor that sets the reset pulse duration via an internal ~26 µA current source charging to ~1.8 V. Using the formula t_d ≈ 2.6×10⁴ × C_T, a 0.1 µF capacitor yields ~2.6 ms. TI recommends 0.1 µF for standard timing, and the TL7702BCDR's CT circuit tolerates ±15% current variation and ±5% reference voltage drift, ensuring predictable timing across temperature and process.

Does TL7702BCDR provide both active-high and active-low reset outputs, and how are they implemented?

Yes, TL7702BCDR provides both active-high RESET (pin 6) and active-low RESET (pin 5) outputs. Both are open-collector, requiring external pullup (for RESET) and pulldown (for RESET) resistors. This architecture allows direct interfacing with diverse microcontrollers-some needing active-low reset, others active-high-and eliminates need for external inverters. The TL7702BCDR guarantees simultaneous assertion/deassertion with matched propagation delays (270–500 ns).

What is the role of the REF pin on TL7702BCDR, and what load can it drive?

The REF pin on TL7702BCDR delivers a precision 2.53 V ±50 mV reference voltage, derived from an internal temperature-compensated bandgap. It is specified for ±500 µA sink/source and requires a 0.1 µF ceramic capacitor to GND for stability. This reference can directly bias ADC references, comparator thresholds, or sensor excitation circuits-eliminating need for a separate voltage reference IC in cost-sensitive TL7702BCDR-based designs.

Can TL7702BCDR operate with supply voltages below 3.3 V, and what is its minimum functional VCC?

TL7702BCDR begins asserting RESET when VCC rises above ~1 V, ensuring valid reset generation during brown-out and power-up-even if the main system rail never reaches nominal voltage. However, its recommended operating supply range is 3.6 V to 18 V. Below 3.6 V, parameters like V_IT– accuracy and REF stability are not guaranteed, though the TL7702BCDR remains functional for basic reset assertion down to 1 V.