Texas Instruments TL7705AID

Overview

TL7705AID from Texas Instruments is a precision supply-voltage supervisor IC designed for reset control in 5-V microcomputer systems. It features a 4.55-V ±0.05-V threshold voltage (V_IT−), 15-mV hysteresis, externally adjustable reset pulse duration via CT pin, and operates across 3.5 V to 18 V supply range. Used in TTL-compatible embedded controllers requiring reliable power-on and brownout reset.

For engineers reviewing the TL7705AID datasheet, TL7705AID pinout, TL7705AID application, or TL7705AID equivalent, key selection criteria include its fixed 4.55-V trip point, dual active-high/active-low open-collector RESET outputs, SOIC-8 industrial-grade (-40°C to +85°C) packaging, and compatibility with standard 5-V logic supply rails.

Technical Context

The TL7705AID integrates a temperature-compensated 2.53-V reference, precision comparator with hysteresis, and RC-based delay timer circuitry. Its SENSE input monitors system supply voltage, triggering RESET assertion when V_SENSE falls below 4.55 V and maintaining it for a user-defined duration set by external capacitor CT.

It supports both direct V_CC monitoring and resistor-divider configurations at SENSE, delivers ±16 mA output drive capability on RESET/RESET pins, and maintains functional stability over full industrial temperature range with <3 mA quiescent current.

Key Specifications

Pinout & Package

TL7705AID is housed in an 8-pin SOIC (D) package measuring 4.90 mm × 3.91 mm, with gull-wing leads and RoHS-compliant NiPdAu plating. It is rated MSL Level-1 (unlimited reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G33DBVR and MAX809SEUR+T, TL7705AID uniquely provides a 4.55-V trip point matched to 5-V TTL margins, user-adjustable reset duration via CT, dual complementary outputs, and a buffered reference output-making it irreplaceable in legacy and industrial 5-V microcontroller reset applications requiring design flexibility and precision.

Availability

TL7705AID is available at Aetrix Electronics and suitable for microprocessor power sequencing, industrial PLC controller reset, automotive body control modules, and TTL-compatible communication interface reset requiring stable component supply across extended temperature ranges.

Supply support for TL7705AID 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 with emphasis on reliability, longevity, and industrial-grade qualification.

The TL77xxA product line was engineered specifically as cost-effective, robust supply-voltage supervisors for microcomputer and microprocessor reset control in industrial, automotive, and computing applications demanding precision thresholds and configurable timing.

FAQ

What is the exact reset threshold voltage of TL7705AID and how tightly is it specified?

The TL7705AID has a guaranteed negative-going input threshold voltage (V_IT−) of 4.55 V with a maximum deviation of ±0.05 V across the full industrial temperature range (–40°C to +85°C). This 4.55-V trip point is laser-trimmed during manufacturing and explicitly validated per Electrical Characteristics Table 6.5 in the SLVS028K datasheet. The value is specific to TL7705AID and differs from other TL77xxA variants like TL7702A (2.53 V) or TL7709A (7.6 V).

Does TL7705AID support both active-high and active-low reset signaling?

Yes, TL7705AID provides two complementary open-collector reset outputs: RESET (Pin 6, active-high) and RESET (Pin 5, active-low). Both outputs are asserted simultaneously during undervoltage or power-on events and deassert after the CT-set delay. Each can sink or source up to 16 mA, enabling direct interface with standard TTL/CMOS inputs-no level-shifting or inversion logic is required when using TL7705AID in dual-signaling architectures.

Can TL7705AID monitor voltages higher than 5 V directly at its SENSE pin?

Yes, TL7705AID's SENSE pin accepts input voltages up to 10 V (per Recommended Operating Conditions, Section 6.3), making it suitable for monitoring higher rails-such as 12-V or 15-V supplies-when used with an external resistor divider. The internal comparator compares the divided voltage against its 4.55-V threshold, preserving accuracy as long as the divider ratio is stable and loading is minimized. Direct connection to >5-V rails without scaling is supported only up to 10 V.

What is the purpose of the REF pin on TL7705AID and is it mandatory to use?

The REF pin (Pin 1) delivers a precision 2.53-V temperature-compensated reference voltage, usable for external circuitry such as ADC references or bias networks. While not mandatory for basic reset operation, TI specifies a 0.1-µF capacitor between REF and GND to suppress fast transients that could cause false triggering. Omitting this capacitor risks unreliable reset behavior under noisy supply conditions, so it is a required design practice-not optional-even when REF is unused.

How does TL7705AID behave during power-down and what is its minimum functional supply voltage?

During power-down, TL7705AID maintains valid reset assertion until V_CC falls below approximately 2 V (per Detailed Description Section 8.1). Below this level, outputs become undefined. Its minimum guaranteed operating supply is 3.5 V (Section 6.3), and the reset generator activates once V_CC reaches ~3.6 V during power-up. This ensures TL7705AID remains fully functional across the entire 3.5–18 V range and provides predictable behavior at both power-on and power-off transitions.