Texas Instruments TL7705ACDRG4

Overview

TL7705ACDRG4 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 dual active-high/active-low open-collector RESET outputs. It operates across 3.5 V to 18 V supply range and supports industrial temperature (0°C to 70°C).

For engineers reviewing the TL7705ACDRG4 datasheet, TL7705ACDRG4 pinout, TL7705ACDRG4 application, or TL7705ACDRG4 equivalent, this page delivers verified functional identity, validated SOIC-8 pin mapping, confirmed 4.55-V supervision threshold, real-world timing behavior (CT-dependent delay), and two technically documented alternative parts for 5-V system reset design.

Technical Context

The TL7705ACDRG4 implements a precision bandgap-referenced comparator with temperature-compensated voltage sensing at the SENSE input, triggering reset when V_SENSE falls below 4.55 V. Its internal delay timer uses an external capacitor on the CT pin, with delay time calculated as t_d = 1.3 × 10⁴ × C_T (seconds). The REF pin provides a stable 2.53 V ±0.05 V reference usable for external circuitry.

It delivers dual complementary reset signals: RESET (active-low, open-collector) and RESET̅ (active-high, open-collector), both rated for ±16 mA output current. The device enters undefined output state only when V_CC drops below 2 V, ensuring robust power-down behavior in 5-V systems.

Key Specifications

Pinout & Package

TL7705ACDRG4 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 moisture sensitivity rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL7705ACDRG4, TPS3808G01QDBVRQ1 offers tighter threshold tolerance and automotive qualification but sacrifices CT-based delay adjustability and REF utility; MAX691CPA+ adds watchdog capability at the cost of inflexible long-duration reset and no reference output.

Availability

TL7705ACDRG4 is available at Aetrix Electronics and suitable for microprocessor reset control, 5-V embedded controller supervision, legacy TTL system monitoring, and multi-supply sequencing applications requiring stable component supply and long-term industrial availability.

Supply support for TL7705ACDRG4 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 decades of expertise in high-reliability industrial and automotive ICs.

The TL77xxA product line was engineered specifically as precision supply-voltage supervisors for microcomputer and microprocessor reset control, emphasizing threshold accuracy, temperature stability, and flexible timing in cost-sensitive embedded systems.

FAQ

What is the exact reset threshold voltage of TL7705ACDRG4?

The TL7705ACDRG4 has a guaranteed negative-going input threshold voltage (V_IT−) of 4.55 V ±0.05 V at 25°C, with 15-mV hysteresis. This value is trimmed at wafer test and applies specifically to the TL7705A variant within the TL77xxA family. The TL7705ACDRG4 maintains this specification across its 0°C to 70°C operating range.

Does TL7705ACDRG4 require external components to function?

Yes, TL7705ACDRG4 requires three external components for basic operation: a 0.1-µF capacitor from REF to GND for reference stability, a timing capacitor (CT) from Pin 3 to GND to set reset pulse duration, and pull-up resistors on RESET and RESET̅ outputs due to their open-collector configuration. These are explicitly required per the datasheet's "Parameter Measurement Information" and "Typical Application" sections.

Can TL7705ACDRG4 monitor voltages other than 5 V?

No - TL7705ACDRG4 is factory-trimmed for a fixed 4.55-V threshold and is intended specifically for 5-V systems. While the SENSE input can tolerate up to 20 V, the internal comparator trip point is not adjustable; alternate variants like TL7709A (7.6 V) or TL7712A (10.8 V) serve higher-voltage rails. Using TL7705ACDRG4 for non-5-V rails would result in incorrect reset assertion.

What is the purpose of the REF pin on TL7705ACDRG4?

The REF pin on TL7705ACDRG4 delivers a precision 2.53 V ±0.05 V temperature-compensated reference voltage, usable as a stable bias source for external circuitry such as ADC references, sensor excitation, or comparator thresholds. It must be decoupled with a 0.1-µF capacitor to GND to suppress noise and ensure supervisor accuracy.

Is TL7705ACDRG4 pin-compatible with other TL77xxA variants?

Yes - all TL77xxA devices, including TL7705ACDRG4, share identical SOIC-8 (D), PDIP-8 (P), and SO-8 (PS) packages and pinouts. The SENSE, RESET, RESET̅, CT, REF, RESIN, GND, and V_CC assignments are consistent across TL7702A, TL7705A, TL7709A, TL7712A, and TL7715A. Only the internal threshold voltage differs between variants.