Texas Instruments TL7705ACD

Overview

TL7705ACD 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 (e.g., 1.3 ms with 0.1 µF), and operates across 3.5 V to 18 V supply range. Used in TTL-based embedded controllers requiring reliable power-on and brownout reset.

For engineers reviewing the TL7705ACD datasheet, TL7705ACD pinout, TL7705ACD application, or TL7705ACD equivalent, this page delivers verified specifications, SOIC-8 package details, dual active-high/active-low reset outputs, temperature-compensated reference (2.53 V typ), and real-world implementation guidance for microprocessor reset circuits.

Technical Context

The TL7705ACD integrates a precision bandgap voltage reference, comparator with hysteresis, delay timer controlled by external capacitor CT, and dual open-collector reset outputs (RESET and RESET). Its SENSE input monitors system supply voltage, triggering reset when falling below 4.55 V and releasing after hysteresis and programmable delay.

It functions as a standalone reset controller without external logic: internal thyristor-based timing ensures deterministic reset assertion during power-up (V_CC ≥ 3.6 V) and undervoltage events, while REF output provides a stable 2.53 V reference usable for auxiliary circuitry.

Key Specifications

Pinout & Package

TL7705ACD is housed in an 8-pin SOIC (D) package (4.90 mm × 3.91 mm body), RoHS-compliant, with NIPDAU lead finish and Level-1 MSL rating (260 °C peak reflow).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL7705ACP and TPS3808G15DBVR, TL7705ACD uniquely combines adjustable reset timing, dual complementary outputs, and a buffered reference voltage in a standard SOIC-8 package-making it optimal for cost-sensitive, 5-V TTL-compatible embedded reset applications requiring design flexibility.

Availability

TL7705ACD is available at Aetrix Electronics and suitable for microprocessor power-up sequencing, 5-V embedded controller reset, and multi-rail system supervision requiring stable component supply and long-term production continuity.

Supply support for TL7705ACD 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 company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and consumer markets.

The TL77xxA product line was engineered specifically as precision, low-cost reset supervisors for microcomputer and microprocessor systems-emphasizing threshold accuracy, hysteresis stability, and external timing flexibility over ultra-low power or digital configurability.

FAQ

What is the exact reset threshold voltage of TL7705ACD?

The TL7705ACD has a guaranteed negative-going input threshold voltage (V_IT−) of 4.5 V to 4.6 V at 25 °C, with a typical value of 4.55 V. This threshold is laser-trimmed and temperature-compensated, ensuring consistent 5-V rail monitoring across its 0 °C to +70 °C operating range. The TL7705ACD datasheet specifies this parameter under Electrical Characteristics (Section 6.5).

Does TL7705ACD require external pull-up resistors on its reset outputs?

Yes, TL7705ACD features open-collector RESET and RESET outputs, so external pull-up resistors are mandatory for proper logic-level definition. A 10-kΩ resistor to V_CC is commonly used on RESET for TTL-compatible high-level signaling, while RESET may be pulled up or left floating depending on downstream logic requirements. The TL7705ACD application schematic (Figure 8) confirms this design practice.

Can TL7705ACD monitor voltages other than 5 V?

No-TL7705ACD is factory-trimmed for a fixed 4.55 V threshold and is intended exclusively for 5-V systems. For other rails, TI offers TL7702A (2.5 V), TL7709A (7.6 V), TL7712A (10.8 V), and TL7715A (13.5 V). While SENSE can accept up to 20 V, the internal comparator trip point remains fixed at 4.55 V; using it on non-5-V rails would result in incorrect reset behavior.

What is the function of the REF pin on TL7705ACD?

The REF pin on TL7705ACD provides a buffered 2.53 V (typ) temperature-compensated reference voltage, stable within ±10 mV over its full 3.5–18 V supply range. It is intended for bypassing with a 0.1 µF capacitor to GND to suppress noise, and may also serve as a precision reference for external comparators or ADC biasing-adding system-level utility beyond basic reset control.

Is TL7705ACD pin-compatible with other TL77xxA variants?

Yes, all TL77xxA devices-including TL7705ACD, TL7702A, TL7709A, TL7712A, and TL7715A-share identical SOIC-8, PDIP-8, and SO-8 pinouts and terminal functions. This allows direct substitution in the same PCB footprint when changing threshold requirements, provided the SENSE input voltage remains within the absolute maximum rating (–0.3 V to 20 V) for the selected variant.