Texas Instruments TL7705ACDG4

Overview

TL7705ACDG4 from Texas Instruments is a precision supply-voltage supervisor IC designed as a reset controller for 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 (e.g., 1.3 ms with 0.1 µF), and dual active-high/active-low open-collector RESET outputs. It operates from 3.5 V to 18 V and is used in TTL-compatible embedded controllers requiring reliable power-on and brownout reset.

For engineers reviewing the TL7705ACDG4 datasheet, TL7705ACDG4 pinout, TL7705ACDG4 application, or TL7705ACDG4 equivalent, key selection criteria include its fixed 4.55-V trip point, SOIC-8 package compatibility, temperature-stable reference (±16 mV over –40°C to +85°C), and support for external timing capacitor adjustment - critical for deterministic reset timing in industrial microcontroller units.

Technical Context

The TL7705ACDG4 implements a precision bandgap-based voltage reference and comparator architecture to monitor the SENSE input against a trimmed 4.55-V threshold. Its internal delay timer is triggered upon positive-going threshold crossing and generates a user-defined reset pulse width via external capacitor CT (td = 1.3 × 10⁴ × C_T seconds).

It delivers dual complementary reset signals (RESET and RESET) with open-collector outputs, enabling flexible interface with both active-low and active-high reset logic. The device remains functional down to V_CC = 3.5 V and guarantees operation up to 18 V, with built-in ESD protection (1000 V HBM) and thermal shutdown immunity up to 150°C junction temperature.

Key Specifications

Pinout & Package

TL7705ACDG4 is housed in an 8-pin SOIC (D) package measuring 4.90 mm × 3.91 mm, with standard JEDEC MS-012AC footprint and RoHS-compliant NiPdAu lead finish. It is rated MSL Level-1 (unlimited floor life at ≤30°C/60% RH) and compatible with standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G01QDBVRQ1 and MAX692CPA+, TL7705ACDG4 uniquely combines a 4.55-V TTL-matched threshold, user-adjustable reset duration via CT, on-chip 2.53-V reference, and SOIC-8 commercial-grade packaging - making it irreplaceable for cost-sensitive, 5-V microcontroller reset applications requiring design flexibility and proven field reliability.

Availability

TL7705ACDG4 is available at Aetrix Electronics and suitable for microcontroller power sequencing, industrial PLC I/O modules, embedded network gateways, and medical diagnostic instruments requiring stable component supply and long-term obsolescence management.

Supply support for TL7705ACDG4 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 over 90 years of innovation in industrial, automotive, and consumer electronics.

The TL77xxA family was engineered specifically as cost-effective, precision supply-voltage supervisors for microcomputer and microprocessor reset control - emphasizing threshold accuracy, timing flexibility, and robustness in unregulated or noisy power environments.

FAQ

What is the exact reset threshold voltage of the TL7705ACDG4?

The TL7705ACDG4 has a nominal negative-going input threshold voltage (V_IT−) of 4.55 V, with a guaranteed range of 4.50 V to 4.60 V at 25°C. This value is trimmed during manufacturing and remains stable across temperature (±16 mV from –40°C to +85°C), making it ideal for 5-V TTL system supervision where precise brownout detection is required. The TL7705ACDG4 uses this threshold to assert RESET when the SENSE input falls below this level.

How do I configure the reset pulse duration for TL7705ACDG4?

The reset pulse duration of TL7705ACDG4 is set by an external capacitor connected to the CT pin (Pin 3). Using the formula t_d = 1.3 × 10⁴ × C_T (where C_T is in farads), a 0.1 µF capacitor yields approximately 1.3 ms. This timing ensures sufficient hold time for microcontroller initialization. The TL7705ACDG4 requires no resistor - only the capacitor - and must be placed close to Pin 3 with short traces to minimize noise coupling.

Does TL7705ACDG4 provide a usable reference voltage output?

Yes, TL7705ACDG4 provides a buffered, temperature-compensated 2.53-V reference voltage at the REF pin (Pin 1). It delivers up to ±1 mA with <±10 mV variation across the full 3.5–18 V supply range and <±16 mV drift from –40°C to +85°C. This output is intended for external use - such as biasing ADC references or op-amp circuits - and requires a 0.1 µF ceramic capacitor to GND for stability, as specified in the TL7705ACDG4 datasheet.

Can TL7705ACDG4 monitor voltages other than 5 V?

TL7705ACDG4 is optimized for 5-V systems with its 4.55-V threshold, but it can supervise higher rails using a resistor divider on the SENSE input - though this introduces tolerance stacking and temperature drift. For dedicated 12-V or 15-V monitoring, TI offers TL7712A (10.8-V threshold) and TL7715A (13.5-V threshold) in the same family. The TL7705ACDG4 itself does not support internal threshold adjustment; its trip point is fixed and unchangeable.

What package and temperature grade does TL7705ACDG4 use?

TL7705ACDG4 is packaged in an 8-pin SOIC (D) body measuring 4.90 mm × 3.91 mm, with NiPdAu lead finish and MSL Level-1 rating. It is specified for commercial temperature operation from 0°C to +70°C (denoted by the "C" suffix). This differs from the "I" grade (TL7705AIDxxx), which extends to –40°C to +85°C. The "G4" suffix indicates TI's green, RoHS-compliant packaging standard.