Texas Instruments TLC7733QPW

Overview

TLC7733QPW from Texas Instruments is a micropower supply voltage supervisor IC designed for reset control in microcomputer and microprocessor systems. It features a fixed 2.93 V negative-going input threshold voltage at SENSE, programmable delay time via external capacitor (td = 2.1 × 10⁴ × CT), and operates across –40°C to 125°C. Its defined RESET output from VDD ≥1 V enables reliable power-on reset generation in battery-backed static RAM applications.

For engineers reviewing the TLC7733QPW datasheet, TLC7733QPW pinout, TLC7733QPW application, or TLC7733QPW equivalent, key selection considerations include its 2.93 V precision voltage sensing threshold, 16 µA maximum supply current, totem-pole output drive capability, DRB package thermal performance, and support for power-down control of static RAM during brownout events.

Technical Context

The TLC7733QPW implements a precision voltage monitor with temperature-compensated internal reference and hysteresis (70 mV) to prevent oscillation near threshold. During power-up, RESET asserts when VDD reaches 1 V and remains active until SENSE exceeds 2.93 V and the externally programmed delay td expires.

It supports dual-mode operation: standard undervoltage supervision and power-down control for static RAM with battery backup. When CONTROL is grounded, RESET becomes active-high, enabling automatic chip-select disable during power failure-provided TLC7733QPW itself is powered by the backup source.

Key Specifications

Pinout & Package

The TLC7733QPW is housed in an 8-pin TSSOP (PW) package with 0.65 mm pitch, measuring 3.0 mm × 4.4 mm × 1.2 mm. This RoHS-compliant, surface-mount package supports automated assembly and offers improved thermal dissipation over PDIP variants.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLC7733IPWR, the TLC7733QPW provides extended temperature operation and superior thermal performance in surface-mount layouts; compared with TPS3808G33DBVR, it delivers deterministic SRAM power-down control and higher drive strength at the cost of higher quiescent current.

Availability

TLC7733QPW is available at Aetrix Electronics and suitable for medical imaging systems, industrial PLC controllers, and automotive body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TLC7733QPW 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 personal electronics markets.

The TLC77xx family was engineered specifically for micropower voltage supervision in safety-critical and battery-sensitive applications-emphasizing precision threshold accuracy, low IDD, and robust power-fail response with SRAM retention capability.

FAQ

What is the exact threshold voltage of the TLC7733QPW and how is it specified?

The TLC7733QPW has a fixed negative-going input threshold voltage of 2.93 V at the SENSE pin, with a tolerance of ±70 mV (2.86 V to 3.00 V) over the full operating temperature range. This value is internally trimmed and does not require external resistors-unlike the TLC7701. The specification appears in the Electrical Characteristics table under "Negative-going input threshold voltage, VIT–" and applies directly to the TLC7733QPW variant.

Does the TLC7733QPW support active-high reset output, and how is it enabled?

Yes, the TLC7733QPW provides both active-low (RESET) and active-high (RESET) outputs simultaneously. No configuration is required-the complementary outputs are always asserted together. RESET goes low and RESET goes high when the supervisor detects undervoltage or manual reset; both return to their inactive states after the delay period expires. This dual-output architecture simplifies interface with MCUs requiring either polarity.

How is the reset delay time set on the TLC7733QPW, and what capacitor value yields a 100 ms delay?

The reset delay time td is set by an external capacitor CT connected from the CT pin to GND, using the formula td = 2.1 × 10⁴ × CT. For a 100 ms (0.1 s) delay, CT = 0.1 / 21000 ≈ 4.76 nF-so a standard 4.7 nF ceramic capacitor is recommended. The datasheet confirms this relationship applies identically to the TLC7733QPW, as verified in the Switching Characteristics table and Timing Diagram section.

Can the TLC7733QPW be used to control battery-backed static RAM, and what pin enables this function?

Yes, the TLC7733QPW supports power-down control for static RAM with battery backup using the CONTROL pin. When CONTROL is tied to GND, the RESET output becomes active-high, allowing direct connection to the SRAM's chip-select (CS) input. During main supply failure, the TLC7733QPW-powered by the backup source-asserts RESET to disable the memory, preserving data integrity. This function is explicitly documented in the Application Information section (Figure 10) for the TLC7733QPW.

What is the maximum supply current of the TLC7733QPW, and under what conditions is it measured?

The maximum supply current (IDD) of the TLC7733QPW is 16 µA, measured under recommended operating conditions: VDD = 5 V, RESIN = VDD, SENSE = VDD ≥ VITmax + 0.2 V, CONTROL = 0 V, and outputs open. This value is confirmed in the Electrical Characteristics table for the TLC77xxQ grade and applies specifically to the TLC7733QPW. Current increases to 150 µA during the delay period (IDD(d)), which is also specified.