Analog Devices Inc. LTC3124EDHC#PBF

Overview

LTC3124EDHC#PBF from Analog Devices (formerly Linear Technology) is a dual-phase, synchronous step-up DC/DC converter with true output disconnect and inrush current limiting, delivering up to 15V output from inputs as low as 1.8V start-up and sustaining operation down to 500mV after startup. It features programmable switching frequency (100kHz–3MHz), 2.5A per-phase peak current limit, and Burst Mode® operation achieving 25µA quiescent current - optimized for powering RF power amplifiers, piezo actuators, and 12V analog rails from single-cell Li-ion or backup capacitors.

For engineers reviewing the LTC3124EDHC#PBF datasheet, LTC3124EDHC#PBF pinout, LTC3124EDHC#PBF application, or LTC3124EDHC#PBF equivalent, key selection considerations include its dual-phase ripple reduction, true output disconnect during shutdown, <1µA shutdown current, adjustable 2.5V–15V output, and thermally enhanced 3mm × 5mm DFN package with exposed PGND pad.

Technical Context

The LTC3124EDHC#PBF employs current-mode PWM control with adaptive slope compensation and dual-phase interleaving at 180° phase shift, enabling reduced output voltage ripple and lower peak inductor current versus single-phase boost topologies. Its internal N-channel MOSFET switches (0.13Ω R_DS(ON)) and P-channel synchronous rectifiers support up to 95% efficiency across load ranges.

Operation includes integrated soft-start (10ms), output overvoltage protection (16.5V clamp), thermal shutdown (170°C), and robust fault handling for short-circuit, overtemperature, and overvoltage conditions. The device supports external clock synchronization and selectable Burst Mode® to maintain high light-load efficiency without audible noise.

Key Specifications

Pinout & Package

Package: 16-lead plastic DFN (DHC), 3mm × 5mm × 0.75mm, thermally enhanced with exposed PGND pad (Pin 17) requiring soldering to PCB ground plane for rated thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous boost converter applications.

Compared with LT8337EDD#PBF and TPS61088RHLR, the LTC3124EDHC#PBF uniquely delivers dual-phase ripple suppression, true output disconnect, and 15V programmable output - making it the only option among the three qualified for precision 12V+ analog rails and RF bias where backfeed prevention and low-noise operation are mandatory.

Availability

LTC3124EDHC#PBF is available at Aetrix Electronics and suitable for RF power amplifier biasing, piezo actuator drive, and 12V analog rail generation requiring stable component supply, long-term lifecycle support, and traceable sourcing for industrial and medical designs.

Supply support for LTC3124EDHC#PBF 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, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC3124EDHC#PBF belongs to Linear's high-efficiency, low-voltage boost converter product line, designed specifically for space-constrained, battery-powered systems demanding wide input range, true output isolation, and ultra-low quiescent current.

FAQ

What is the minimum input voltage required to start up the LTC3124EDHC#PBF?

The LTC3124EDHC#PBF requires a minimum input voltage of 1.6V (typical 1.8V) to initiate startup. Once operating, it sustains regulation with input voltages as low as 500mV - provided the output voltage is set to ≥2.5V. This ultra-low sustain voltage enables maximum energy recovery from deeply discharged batteries or backup capacitors, a key differentiator of the LTC3124EDHC#PBF in portable power applications.

Does the LTC3124EDHC#PBF provide true output disconnect, and how is it implemented?

Yes, the LTC3124EDHC#PBF provides true output disconnect: when the SD pin is pulled low (<0.25V), both internal P-channel synchronous rectifiers are fully turned off, physically isolating VOUT from VIN. This prevents backfeed into the input source and enables safe power sequencing in multi-rail systems - a feature confirmed in the datasheet's "Output Disconnects from Input When Shut Down" specification and functional block diagram.

How is the switching frequency programmed on the LTC3124EDHC#PBF?

The LTC3124EDHC#PBF switching frequency is programmed using an external resistor (R_T) from Pin 8 (RT) to SGND. The relationship is f_SW ≈ 28 / R_T(kΩ) MHz - for example, 28kΩ yields ~1MHz per phase. The oscillator runs at 2× f_SW, and the device supports synchronization to an external clock applied to the PWM/SYNC pin at twice the desired f_SW. This precise programmability is documented in the Electrical Characteristics table and Figure 17.

What thermal performance can be expected from the LTC3124EDHC#PBF in its DFN package?

The LTC3124EDHC#PBF in the 3mm × 5mm DFN (DHC) package has θ_JA = 43°C/W and θ_JC = 5°C/W when the exposed PGND pad (Pin 17) is properly soldered to the PCB ground plane. Junction temperature rise is calculated as T_J = T_A + (P_D × 43°C/W). Failure to solder the exposed pad results in significantly degraded thermal performance - a requirement explicitly stated in the datasheet's package drawings and thermal notes.

Can the LTC3124EDHC#PBF operate with output voltages above 12V, and what is the maximum supported?

Yes, the LTC3124EDHC#PBF supports output voltages up to 15V, adjustable via the FB resistor divider (V_OUT = 1.2V × (1 + R1/R2)). The Absolute Maximum Ratings confirm VOUTA/VOUTB withstand up to 18V, and typical applications demonstrate stable 15V operation. This capability is essential for driving high-voltage piezo actuators and RF power amplifiers - distinguishing the LTC3124EDHC#PBF from many competing boost converters capped at 12.6V or lower.