Analog Devices Inc. LTC3620EDC-1#TRPBF

Overview

LTC3620EDC-1#TRPBF from Analog Devices (formerly Linear Technology) is an ultralow-power, synchronous step-down DC/DC converter optimized for single Li-Ion battery-powered systems requiring 1.1V output at up to 15mA. It integrates P-channel and N-channel MOSFETs, features a 0.6V internal reference, 18μA quiescent current, and operates from 2.9V to 5.5V input. It is used in hearing aids and wireless headsets where minimal footprint and battery longevity are critical.

For engineers reviewing the LTC3620EDC-1#TRPBF datasheet, LTC3620EDC-1#TRPBF pinout, LTC3620EDC-1#TRPBF application, or LTC3620EDC-1#TRPBF equivalent, key selection criteria include its fixed 1.1V output, 50kHz internal frequency clamp, 2mm × 2mm DFN package, low-battery detection (LOBATB), and shutdown current <1μA - all essential for ultra-low-power wearable and medical micro-power designs.

Technical Context

The LTC3620EDC-1#TRPBF employs a variable-frequency, constant-on-time control architecture that dynamically adjusts switching frequency with load current to maximize efficiency across 0.1–15mA. Its internal 0.6V reference enables precise 1.1V regulation via integrated resistive divider, eliminating external feedback components.

It integrates synchronous power switches (R_DS(ON) = 2.0Ω P-FET / 1.0Ω N-FET at 3.6V), features programmable minimum frequency clamping via FMIN/MODE pin (50kHz default), and includes undervoltage lockout (2.8V) and low-battery status (3.0V threshold) with hysteresis.

Key Specifications

Pinout & Package

The LTC3620EDC-1#TRPBF is housed in a thermally enhanced, lead-free 8-lead 2mm × 2mm DFN package (exposed pad = GND). The exposed pad must be soldered to PCB for thermal and electrical grounding.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down regulator applications.

Compared with LTC3620EDC-1#TRPBF, TPS62740DRYR offers dramatically lower IQ but lacks battery monitoring, while MAX17222ETA+ provides higher current and lower IQ yet omits both LOBATB and frequency-noise control - making LTC3620EDC-1#TRPBF uniquely suited for audio-sensitive, battery-aware micro-power systems.

Availability

LTC3620EDC-1#TRPBF is available at Aetrix Electronics and suitable for hearing aids, wireless headsets, and Li-Ion micro-power applications requiring stable component supply, full traceability, and long-term lifecycle support.

Supply support for LTC3620EDC-1#TRPBF 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. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets.

The LTC3620 product line was designed by Linear Technology (acquired by ADI in 2017) specifically for ultralow-power, space-constrained battery-operated devices - emphasizing minimal IQ, small footprint, and intelligent battery interface features like LOBATB and UVLO.

FAQ

What is the output voltage of the LTC3620EDC-1#TRPBF?

The LTC3620EDC-1#TRPBF provides a fixed 1.1V output voltage with ±1.1% tolerance over temperature and line. This is achieved via an internal precision resistor divider referenced to the 0.6V feedback node, eliminating the need for external resistors. The LTC3620EDC-1#TRPBF datasheet specifies V_FB = 1.089V to 1.122V at 25°C, confirming its role as a factory-programmed variant distinct from the adjustable LTC3620.

Does the LTC3620EDC-1#TRPBF require external feedback resistors?

No, the LTC3620EDC-1#TRPBF does not require external feedback resistors. It integrates an internal resistive divider that sets V_FB to 1.1V, and the VFB pin must be connected directly to VOUT per the datasheet. This simplifies design, reduces component count, and improves reliability in space-constrained applications such as hearing aids where the LTC3620EDC-1#TRPBF is commonly deployed.

What is the function of the LOBATB pin on the LTC3620EDC-1#TRPBF?

The LOBATB pin on the LTC3620EDC-1#TRPBF is an open-drain low-battery status output that pulls low when VIN falls below 3.0V (typical), with 100mV hysteresis. It enables host microcontrollers to monitor battery health and initiate graceful shutdown before undervoltage lockout (UVLO at 2.8V) occurs. This feature is critical in wearable medical devices powered by the LTC3620EDC-1#TRPBF, where battery state awareness directly impacts user safety and data integrity.

How does the FMIN/MODE pin affect the LTC3620EDC-1#TRPBF's operation?

The FMIN/MODE pin on the LTC3620EDC-1#TRPBF controls the minimum switching frequency: pulling it low sets a 50kHz clamp to suppress audio-band noise; applying a 20–300kHz external clock overrides the internal clamp; pulling it high disables clamping entirely. This flexibility allows designers to optimize EMI performance in noise-sensitive applications like wireless headsets using the LTC3620EDC-1#TRPBF, without altering the core regulation behavior or output accuracy.

What package type and thermal requirements apply to the LTC3620EDC-1#TRPBF?

The LTC3620EDC-1#TRPBF uses an 8-lead 2mm × 2mm plastic DFN package with an exposed thermal pad (Pin 9) that must be soldered to the PCB ground plane. This pad is electrically GND and critical for thermal dissipation and noise immunity. With θ_JA = 88.5°C/W, proper pad soldering ensures junction temperature remains within –40°C to 125°C limits even at full 15mA load - a requirement explicitly stated in the LTC3620EDC-1#TRPBF datasheet layout guidelines.