Analog Devices Inc. LT1763CS8-3.3#TRPBF

Product Summary

The Analog Devices LT1763CS8-3.3#TRPBF is a member of the LT1763 series of low dropout (LDO) linear regulators, designed to deliver high performance in noise-sensitive and battery-powered systems. This IC provides a fixed 3.3V output at up to 500mA, delivered in a compact 8-lead SOIC package suitable for surface-mount applications and temperatures ranging from -40°C to +125°C. It offers a blend of low output noise, minimal quiescent current, and robust protection features, making it an optimal choice for engineers looking to balance efficiency and signal integrity in their designs.

Main Functional Attributes of the LT1763CS8-3.3#TRPBF

The LT1763CS8-3.3#TRPBF distinguishes itself as a micropower, low-noise, low-dropout regulator. Its architecture enables an impressively low dropout voltage—only 300mV at 500mA load—which is essential for maximizing usable battery life and supporting applications where input voltage headroom is limited. The regulator's intrinsic output noise is just 20μV RMS (10Hz to 100kHz) with a suitable bypass capacitor, addressing the stringent requirements of instrumentation and RF systems.

The device draws an exceptionally low quiescent current of 30μA (typical), with a shutdown current of less than 1μA—key for extending battery life in portable electronics. The LT1763CS8-3.3#TRPBF is inherently stable with output capacitors as small as 3.3μF, supporting a variety of types (ceramic, tantalum, aluminum) without the need for additional series resistance or special considerations. No protection diodes are required during normal operation.

Electrical Specifications and Performance

The LT1763CS8-3.3#TRPBF is engineered to maintain reliable regulation and well-controlled noise across a wide input voltage range of 1.8V to 20V. It delivers a guaranteed 3.3V output with tight tolerance (typically ±1%) over variations in input voltage and load currents up to 500mA. Its line regulation is rated at 1mV typ over the full input voltage span, ensuring robust supply performance in dynamic conditions. Load regulation figures are equally competitive, with only 7mV typical deviation from 1mA to 500mA.

Dropout voltage—a critical metric for power-sensitive designs—is just 300mV typical at 500mA load, with a guaranteed maximum of 450mV over temperature (TJ ≤ 125°C). Ground pin current (quiescent plus load-dependent) is only 20μA at no load, increasing moderately under maximum load, supporting efficient operation across the entire supply current range.

The LT1763CS8-3.3#TRPBF's power supply rejection ratio (PSRR) reaches 65dB at 120Hz, crucial for attenuating supply ripple and noise from upstream converters. The device is specified for indefinite short-circuit duration.

Safeguard Mechanisms and Reliability

The LT1763CS8-3.3#TRPBF integrates robust protection circuitry to safeguard both IC and system integrity. Its built-in features include overcurrent limitation, thermal shutdown for overtemperature events, as well as reverse battery and reverse output current protection. These measures ensure survivability in unpredictable system environments and simplify power subsystem design by reducing the need for external protection components.

Packaging Types and Environmental Standards

Supplied in an 8-lead SOIC package (3.90mm width, surface-mount), the LT1763CS8-3.3#TRPBF is interchangeable with standard SO8 footprints common in low-profile designs. The package's thermal properties (θJA = 70°C/W, θJC = 35°C/W) allow reliable operation within the full industrial temperature range. For broader design compatibility, the LT1763 series also features DFN packaging and different fixed output voltages and temperature-qualified grades (C, I, MP).

Environmental and regulatory compliance are met with ROHS3 and REACH unaffected status. The component is moisture sensitivity level 1 (unlimited floor life), ensuring straightforward handling and assembly.

Possible Alternative or Substitute Parts

When selecting a linear regulator for low noise, high-reliability applications, the LT1763 series offers a comprehensive product family. For 3.3V, 500mA applications where the LT1763CS8-3.3#TRPBF is specified, the following direct variants may serve as alternatives:

LT1763IS8-3.3#TRPBF: Identical electrical characteristics, rated for the same operation and package, with an industrial temperature grade.

LT1763MPDE-3.3#TRPBF: Same electrical core, available in a 12-lead DFN package and qualified to -55°C operation for military/harsh environments.

LT1763CS8-3.3#PBF: Lead-free finish, otherwise electrically identical.

If alternative output voltages are required, the LT1763 family supports fixed values (1.5V, 1.8V, 2.5V, 3V, 5V), as well as an adjustable version with output from 1.22V to 20V via external resisters. These options provide flexibility in standardization across product lines.

Use Cases for the LT1763CS8-3.3#TRPBF

The LT1763CS8-3.3#TRPBF excels in environments where quiet, efficient regulation is paramount. Engineers will find it particularly suitable in:

Battery-powered industrial modules: Low quiescent current and low dropout characteristics maximize battery life.

Noise-sensitive instrumentation: Ultra-low output noise and high PSRR directly benefit measurement resolution and system accuracy.

Cellular and RF circuits: Clean supply rails support analog front ends and transceiver blocks, mitigating unwanted spur and intermodulation.

General power conditioning: Use as a post-regulator to “clean up” switch-mode supplies for sensitive analog or mixed-signal subsystems.

Given its output stability with small ceramic capacitors, the LT1763CS8-3.3#TRPBF fits space-constrained layouts and high-density assemblies.

Conclusion

The Analog Devices LT1763CS8-3.3#TRPBF offers a blend of low noise, low dropout, and rugged protection that addresses the critical needs of modern, battery-powered, and noise-sensitive electronic designs. With flexible package options, robust reliability, and family variants to suit a wide range of voltage and environmental requirements, it supports engineers in achieving optimal performance—while maintaining design cycle efficiency and long-term supply assurance. The LT1763CS8-3.3#TRPBF stands out as a ready solution for challenging precision and portable power applications.