Analog Devices Inc. LT3483IDC#TRMPBF

Overview

LT3483IDC#TRMPBF from Analog Devices (formerly Linear Technology) is a micropower inverting DC/DC converter with integrated 40V Schottky diode and one-resistor feedback, delivering regulated negative outputs up to –38V from 2.5V–16V input. It features 40µA quiescent current, 300ns fixed off-time control, and operates across –40°C to 125°C in an 8-lead 2mm × 2mm DFN package. Used in OLED bias, handheld computers, and battery backup systems.

For engineers reviewing the LT3483IDC#TRMPBF datasheet, LT3483IDC#TRMPBF pinout, LT3483IDC#TRMPBF application, or LT3483IDC#TRMPBF equivalent, key selection criteria include its 200mA switch current limit, 200mV V_CE(SAT), internal Schottky integration, shutdown current <1µA, and compatibility with low-profile inductors for space-constrained portable designs.

Technical Context

The LT3483IDC#TRMPBF employs a constant off-time (COT) control architecture with a precisely trimmed 10µA feedback current reference, enabling single-resistor output programming and eliminating feedback loading. Its internal 40V/200mA NPN power switch and integrated Schottky diode support inverting charge pump and flyback topologies without external diodes.

Operation relies on FB pin hysteresis (10mV), 300ns minimum off-time, and proprietary current limiting that protects the switch during output short-circuit events-even at 16V input. The device enters ultra-low-power shutdown (<1µA) when SHDN is pulled low, and resumes regulation with minimal startup delay.

Key Specifications

Pinout & Package

LT3483IDC#TRMPBF is housed in an 8-lead plastic DFN package (2mm × 2mm × 0.75mm) with exposed thermal pad (Pin 9, GND). The package supports high-density PCB layouts and efficient heat dissipation when the exposed pad is soldered to a ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar inverting DC/DC converter applications.

Compared with LT3483IDC#TRMPBF, LT3483AIDC#TRPBF offers double the switch current for higher output capability without layout change, while LT1931EDE#TRPBF trades 145× higher quiescent current for faster switching and smaller magnetics-making each optimal for distinct power vs. size vs. efficiency trade-offs.

Availability

LT3483IDC#TRMPBF is available at Aetrix Electronics and suitable for OLED bias, handheld computing power management, and battery backup systems requiring stable component supply across extended temperature ranges.

Supply support for LT3483IDC#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 acquired Linear Technology in 2017 and continues to manufacture and support its high-performance analog and power management portfolio.

The LT3483 series belongs to Linear's micropower inverting DC/DC converter product line, designed specifically for space- and power-constrained portable electronics needing compact, transformerless negative voltage generation.

FAQ

What is the maximum negative output voltage achievable with the LT3483IDC#TRMPBF?

The LT3483IDC#TRMPBF supports regulated negative outputs up to –38V, enabled by its 40V internal switch rating and robust inverting charge pump topology. This capability eliminates the need for external transformers in high-voltage bias applications such as OLED displays and CCD imaging sensors. Output voltage is set by a single feedback resistor (R₁ = –V_OUT/10µA), and stability is maintained across the full –40°C to 125°C operating range.

Does the LT3483IDC#TRMPBF require an external Schottky diode?

No, the LT3483IDC#TRMPBF integrates a 40V Schottky diode internally-its anode is accessible at the D pin. This integration reduces component count, PCB area, and reverse-recovery losses compared to discrete solutions. The internal diode is rated for 350mA peak current and exhibits 0.64V forward drop at 150mA, making it suitable for typical inverting charge pump and flyback configurations without external diode supplementation.

How does the LT3483IDC#TRMPBF achieve ultra-low quiescent current?

The LT3483IDC#TRMPBF achieves 40µA quiescent current in active mode and <1µA in shutdown through a combination of optimized bias circuitry, low-leakage process technology, and intelligent functional gating. During light-load operation, the constant off-time controller minimizes switching activity, and internal comparators disable non-essential blocks when FB voltage falls below hysteresis threshold. In shutdown mode, the entire control loop and power switch are disabled, leaving only leakage paths active-enabling multi-year battery life in backup applications.

Can the LT3483IDC#TRMPBF be used in inverting flyback configuration?

Yes, the LT3483IDC#TRMPBF supports both inverting charge pump and inverting flyback topologies. In flyback mode, it uses a coupled inductor (e.g., SDQ12 or LPD3015) between SW and D pins, enabling efficient –5V generation from 2.5V–6V inputs. The device's 300ns minimum off-time and 200mA switch current limit are well-matched to this configuration, and its proprietary short-circuit protection remains fully active-preventing damage even during sustained output faults at 16V input.

What is the recommended PCB layout practice for the LT3483IDC#TRMPBF DFN package?

For the LT3483IDC#TRMPBF DFN package, the exposed thermal pad (Pin 9) must be soldered to a solid PCB ground plane to ensure θ_JA = 88.5°C/W thermal performance. High-di/dt traces (SW and D) must be kept short and wide, with the flying capacitor placed adjacent to the D and SW pins. A continuous ground plane beneath the IC minimizes EMI and provides low-impedance return paths. Avoid routing sensitive signals (e.g., FB) near SW/D nodes, and place the 1µF VIN bypass capacitor within 2mm of the VIN pin using short, direct traces.