Analog Devices Inc. LT3048IDC-3.3#TRMPBF

Overview

LT3048IDC-3.3#TRMPBF from Analog Devices is a dual-stage low-noise bias generator integrating a 2.2MHz fixed-frequency boost regulator and a low-dropout linear regulator in an 8-lead 2mm × 2mm DFN package. It delivers a precise 3.3V output at up to 40mA from 2.7V–4.8V single-cell Li-ion input, achieving <120µVRMS (10Hz–100kHz) noise and <500µVP-P ripple for sensor bias and op amp supply applications.

For engineers reviewing the LT3048IDC-3.3#TRMPBF datasheet, LT3048IDC-3.3#TRMPBF pinout, LT3048IDC-3.3#TRMPBF application, or LT3048IDC-3.3#TRMPBF equivalent, key selection criteria include guaranteed 3.3V ±1.5% output accuracy over load (100µA–40mA) and temperature (–40°C to 125°C), integrated Schottky diode, load disconnect in shutdown, and 1nF BYP capacitor support for noise reduction.

Technical Context

The LT3048IDC-3.3#TRMPBF employs peak current-mode control in its boost stage, operating at 2.2MHz with 86% maximum duty cycle and 400mA typical switch current limit. Its LDO input (LDOIN) is regulated to 1.1V above LDOOUT, enabling optimized ripple rejection and transient response while minimizing power dissipation during overload.

Unlike the adjustable LT3048 variant, this fixed-output version eliminates external feedback resistors and uses internal regulation to maintain 3.300V nominal output with 9mV load regulation (∆I_LOAD = 100µA to 40mA) and 1.235V reference voltage tolerance of ±1.5% over full temperature range.

Key Specifications

Pinout & Package

LT3048IDC-3.3#TRMPBF is housed in an 8-lead 2mm × 2mm plastic DFN package with exposed thermal pad (Pin 9, GND). The package features 0.45mm pitch, 0.23mm lead thickness, and requires soldering of the exposed pad to PCB ground for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise bias generator applications.

Compared with LT3048EDC-3.3#TRPBF, the LT3048IDC-3.3#TRMPBF guarantees full –40°C to 125°C operation, making it suitable for harsh environments; compared with LT3095EDD#TRPBF, it offers smaller size and lower IQ but lacks dual outputs and sub-5µVRMS noise performance.

Availability

LT3048IDC-3.3#TRMPBF is available at Aetrix Electronics and suitable for portable instrumentation, sensor biasing, op amp supply, and low-power IoT node designs requiring stable component supply, guaranteed industrial temperature range, and low-noise DC/DC conversion.

Supply support for LT3048IDC-3.3#TRMPBF 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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, communications, automotive, and consumer markets.

The LT3048 series was designed specifically for ultra-low-noise bias generation in precision analog systems, combining boost and LDO regulation to overcome input voltage limitations while preserving signal integrity.

FAQ

What is the guaranteed output voltage accuracy of the LT3048IDC-3.3#TRMPBF over temperature and load?

The LT3048IDC-3.3#TRMPBF delivers 3.300V ±1.5% over the full –40°C to 125°C junction temperature range and for load currents from 100µA to 40mA. This is confirmed by the Electrical Characteristics table specifying min/max values of 3.217V to 3.383V under those conditions, ensuring reliable biasing for precision analog circuits without external trimming.

Does the LT3048IDC-3.3#TRMPBF require external feedback resistors?

No, the LT3048IDC-3.3#TRMPBF does not require external feedback resistors. As a fixed-output variant, it integrates internal resistor networks to regulate LDOOUT to 3.3V. Unlike the adjustable LT3048, it omits the FB pin and uses Pin 5 exclusively as LDOOUT, simplifying layout and eliminating resistor tolerance errors.

What is the purpose of the BYP pin on the LT3048IDC-3.3#TRMPBF?

The BYP pin on the LT3048IDC-3.3#TRMPBF accepts an optional 1nF capacitor connected between LDOOUT and BYP to reduce output voltage noise and improve transient response. This capacitor also provides soft-start functionality for the LDO stage, limiting inrush current during power-up without requiring external circuitry.

Can the LT3048IDC-3.3#TRMPBF operate from a 2.7V input source?

Yes, the LT3048IDC-3.3#TRMPBF is fully specified to operate from 2.7V input, the minimum of its 2.7V–4.8V range. At 2.7V input and 40mA load, typical efficiency is ~40% (per TA06b curve), and output remains within 3.217V–3.383V tolerance, making it suitable for end-of-life single-cell Li-ion battery operation.

How does the LT3048IDC-3.3#TRMPBF achieve low output noise despite using a switching boost stage?

The LT3048IDC-3.3#TRMPBF achieves low output noise by cascading a switching boost regulator with a high-PSRR LDO stage, where BSTOUT is regulated to 1.1V above LDOOUT. This architecture leverages the LDO's inherent ripple rejection (>60dB at 1MHz) while minimizing thermal noise via low-noise reference design, resulting in <120µVRMS (10Hz–100kHz) at LDOOUT.