Microchip Technology TC1173-3.3VUA

Overview

TC1173-3.3VUA from Microchip Technology Inc. is a fixed-output CMOS low dropout (LDO) voltage regulator delivering 3.3 V ±0.5% at up to 300 mA, with ultra-low 50 µA typical supply current and 240 mV typical dropout voltage at full load. It features an open-drain ERROR output for out-of-regulation detection, shutdown control (SHDN), and Bypass input for noise reduction-designed for battery-powered medical instruments and portable computing systems.

For engineers reviewing the TC1173-3.3VUA datasheet, TC1173-3.3VUA pinout, TC1173-3.3VUA application, or TC1173-3.3VUA equivalent, key selection criteria include its 300 mA output capability, 0.05 µA shutdown current, ±0.5% output accuracy, 240 mV dropout at 300 mA, and MSOP-8 package compatibility with space-constrained PCB layouts.

Technical Context

The TC1173-3.3VUA employs CMOS pass transistor architecture enabling stable regulation across 0–300 mA load range without supply current increase-unlike bipolar LDOs. Its internal feed-forward compensation ensures fast transient response to step-load changes, while thermal shutdown (150°C trip) and overcurrent protection operate independently of external components.

ERROR output asserts low when VOUT drops >5% below nominal (e.g., <3.135 V for 3.3 V version), with 50 mV hysteresis referenced to VR. The Bypass pin accepts a 470 pF capacitor to reduce reference noise, lowering output noise to 260 nV/√Hz at 1 kHz-critical for analog-sensor and RTC backup power rails.

Key Specifications

Pinout & Package

TC1173-3.3VUA is housed in an 8-pin MSOP package (3.0 mm × 3.0 mm × 1.1 mm), optimized for high-density portable designs. Thermal resistance θ_JA is 200°C/W, requiring minimal copper pour for 155 mW dissipation at 55°C ambient.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with MCP1700-3302E/TO and TPS76333QDBVRQ1, TC1173-3.3VUA uniquely combines 300 mA output, ERROR flag, Bypass noise reduction, and 50 µA IQ in an MSOP-8 footprint-making it optimal for battery-critical, noise-sensitive portable instrumentation where integrated diagnostics are essential.

Availability

TC1173-3.3VUA is available at Aetrix Electronics and suitable for portable medical sensors, RTC/SRAM backup power, and handheld test equipment requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TC1173-3.3VUA 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

Microchip Technology Inc. is a U.S.-based semiconductor manufacturer specializing in microcontrollers, analog devices, and power management ICs, with ISO/TS-16949 certified wafer fabrication and design centers globally.

The TC1173 product line was designed specifically for ultra-low-power, high-accuracy linear regulation in battery-operated systems-emphasizing extended runtime, precise voltage control, and integrated system monitoring via ERROR and SHDN pins.

FAQ

What is the minimum input voltage required for TC1173-3.3VUA to maintain regulation?

The TC1173-3.3VUA requires VIN ≥ VOUT + dropout voltage. With a typical 240 mV dropout at 300 mA, the minimum VIN is 3.54 V. However, per datasheet Note 8, absolute minimum VIN is 2.7 V-so regulation is guaranteed only when VIN ≥ 3.54 V. Below that, TC1173-3.3VUA enters dropout and VOUT declines linearly with VIN.

Can TC1173-3.3VUA be used without the Bypass capacitor?

Yes, TC1173-3.3VUA operates fully functional without the Bypass capacitor. The 470 pF capacitor on the Bypass pin is optional and serves only to reduce output noise from 260 nV/√Hz to lower levels-critical for noise-sensitive analog circuits. If noise performance is not required, the Bypass pin may be left unconnected with no impact on regulation or stability of TC1173-3.3VUA.

How does the ERROR output of TC1173-3.3VUA behave during shutdown?

During shutdown (SHDN pin low), the TC1173-3.3VUA disables its internal regulator, causing VOUT to fall to 0 V and the ERROR output to become inactive (high-impedance). ERROR does not assert low during shutdown-it only signals out-of-regulation events while the device is enabled. Thus, TC1173-3.3VUA's ERROR output is valid only when SHDN is high and VIN is sufficient for regulation.

Is TC1173-3.3VUA stable with ceramic output capacitors?

Yes, TC1173-3.3VUA is stable with ceramic output capacitors ≥1 µF, provided their effective series resistance (ESR) is between 0.1 Ω and 5.0 Ω. Unlike older LDOs, TC1173-3.3VUA does not require high-ESR tantalum or aluminum electrolytic capacitors. Standard X5R/X7R ceramics meet this requirement and are recommended for compact, high-reliability designs using TC1173-3.3VUA.

What is the thermal shutdown behavior of TC1173-3.3VUA?

TC1173-3.3VUA activates thermal shutdown when junction temperature exceeds 150°C, disabling the output until die temperature falls to ~140°C. During shutdown, VOUT drops to 0 V and supply current remains at 0.05 µA. This protection is fully internal-no external components needed-and resets automatically once cooling occurs, ensuring robust operation under sustained overload or poor heatsinking in TC1173-3.3VUA applications.