Texas Instruments TL7705BIDR

Overview

TL7705BIDR from Texas Instruments is a precision supply-voltage supervisor IC designed as a reset controller for 5-V microprocessor systems. It monitors the SENSE input for undervoltage conditions, provides true and complement active-high/active-low RESET outputs, features an externally adjustable reset pulse duration via CT capacitor, and maintains defined RESET behavior down to VCC ≥ 1 V. It is used in industrial control and embedded computing where reliable power-on and brownout reset is required.

For engineers reviewing the TL7705BIDR datasheet, TL7705BIDR pinout, TL7705BIDR application, or TL7705BIDR equivalent, this page delivers verified electrical characteristics, thermal metrics, timing behavior, functional modes, and real-world implementation guidance - all specific to the TL7705BIDR SOIC-8 variant with –40°C to 85°C operating range.

Technical Context

The TL7705BIDR implements a dual-threshold voltage-sensing architecture with hysteresis (30 mV typical) and temperature-compensated internal reference (2.53 V typical at REF). Its reset assertion is triggered when SENSE falls below 4.55 V (VIT–), and deassertion occurs after a user-defined delay determined by external CT capacitor (td ≈ 26 ms per µF).

It supports independent reset control via RESIN input: pulling RESIN low forces RESET high and RESET low regardless of SENSE state, enabling manual or system-initiated reset override. Both RESET outputs are open-collector, requiring external pullup/pulldown resistors (TI recommends 10 kΩ) to ensure clean logic transitions and prevent waveform plateauing.

Key Specifications

Pinout & Package

TL7705BIDR 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-2 (260°C peak reflow, 1-year floor life).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G33DBVR and MAX6816EUT+T, the TL7705BIDR uniquely delivers both true/complement outputs, a usable reference voltage, RESIN override, and precise 4.55-V threshold - making it optimal for robust 5-V microprocessor reset where hardware-level control and signal flexibility are required.

Availability

TL7705BIDR is available at Aetrix Electronics and suitable for industrial automation, building management systems, and embedded computing applications requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for TL7705BIDR 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 control ICs.

The TL77xxB family was engineered specifically for reliable reset control in microprocessor-based systems, emphasizing precision threshold accuracy, temperature stability, and flexible timing - targeting industrial, computing, and communications infrastructure.

FAQ

What is the exact undervoltage detection threshold of the TL7705BIDR?

The TL7705BIDR has a nominal negative-going input threshold (VIT–) of 4.55 V at 25°C, with a full-temperature-range specification of 4.45 V to 4.65 V. This threshold is optimized for supervising standard 5-V power rails and is internally trimmed for accuracy. The device also provides 30 mV typical hysteresis to prevent oscillation during slow supply recovery. All values are confirmed in Section 6.5 of the official TI SLVS037O datasheet for TL7705BIDR.

How does the CT pin on the TL7705BIDR determine reset pulse duration?

The CT pin on the TL7705BIDR connects to an external capacitor that sets the reset pulse width using an internal current source. The relationship is td ≈ 2.6 × 10⁴ × CT, where CT is in farads and td is in seconds - meaning a 0.1 µF capacitor yields ~2.6 ms. TI confirms this formula applies across the full operating temperature range and accounts for ±15% current-source variation. The TL7705BIDR datasheet Figure 6-1 and Section 8.3.2 validate this behavior.

Can the TL7705BIDR operate with a supply voltage below 3.6 V?

No - the TL7705BIDR is specified for recommended operation only from 3.6 V to 18 V (Section 6.3). While its RESET output is defined down to VCC ≥ 1 V for power-fail indication, the device does not guarantee correct internal comparator, reference, or timing function below 3.6 V. Operating outside the recommended range may result in undefined reset behavior or failure to assert/deassert reliably. This limitation is explicitly stated in TI's SLVS037O datasheet.

Why does the TL7705BIDR require both pullup and pulldown resistors on its RESET outputs?

The TL7705BIDR features open-collector RESET (active-high) and RESET (active-low) outputs. RESET requires a pullup resistor to establish a valid HIGH level for the host MCU, while RESET requires a pulldown resistor to define a stable LOW state. TI mandates matched resistor values (e.g., 10 kΩ each) even when only one output is used - to prevent waveform plateauing during switching that could cause undefined logic states or delayed system reset. This requirement is documented in Sections 9.2.1 and 11.1 of the TL7705BIDR datasheet.

Is the TL7705BIDR pin-compatible with other TL77xxB variants like TL7702BIDR or TL7733BIDR?

Yes - the TL7705BIDR shares identical SOIC-8 pinout, electrical interface, and functional block diagram with TL7702BIDR and TL7733BIDR. The only differences are threshold voltages (2.53 V, 4.55 V, and 3.08 V respectively) and minor hysteresis values. All three variants use the same REF, RESIN, CT, SENSE, RESET, RESET, GND, and VCC pin assignments and timing behavior. This compatibility is confirmed in TI's functional block diagram (Figure 8-2) and Pin Functions table (Section 5) for TL7705BIDR.