Analog Devices Inc. LT1615IS5-1#TRPBF

Overview

LT1615IS5-1#TRPBF from Analog Devices (formerly Linear Technology) is a micropower step-up DC/DC converter in a 5-lead ThinSOT package, designed for single-cell battery applications with 1V to 15V input, 100mA switch current limit, and 34V maximum output voltage. It delivers regulated bias for LCDs, powers low-current sensors, and enables compact portable electronics requiring ultra-low quiescent current.

For engineers reviewing the LT1615IS5-1#TRPBF datasheet, LT1615IS5-1#TRPBF pinout, LT1615IS5-1#TRPBF application, or LT1615IS5-1#TRPBF equivalent, key selection criteria include its 1V minimum input, 20µA active quiescent current, 400ns fixed off-time control, 1.23V feedback reference, and ThinSOT-23 thermal performance at –40°C to 85°C.

Technical Context

The LT1615IS5-1#TRPBF implements a constant off-time, current-limited boost topology using an internal NPN power switch with 250mV V_CE(SAT) at 70mA. Its 1.23V ±25mV feedback comparator features 8mV hysteresis and <80nA bias current, enabling precise output regulation across temperature.

Startup and short-circuit protection are handled by adaptive timing: when FB falls below ~600mV, off-time extends to 1.5µs and current limit reduces to ~70mA-reducing average inductor current without external circuitry.

Key Specifications

Pinout & Package

LT1615IS5-1#TRPBF is housed in a 5-lead ThinSOT (SOT-23 variant), 1mm profile, JEDEC SC-74A-compliant package with 0.95mm pitch and exposed pad not connected internally.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-up DC/DC converter applications.

Compared with LT1615IS5-1#TRPBF, LT1307ES5#TRPBF trades shutdown functionality and 100mA capability for deterministic 600kHz operation, while TPS61200DRCR offers higher current and integration at the cost of 1V start-up support - making LT1615IS5-1#TRPBF uniquely suited for deep-discharge single-cell applications.

Availability

LT1615IS5-1#TRPBF is available at Aetrix Electronics and suitable for LCD bias generation, PIN diode driver circuits, and low-power sensor node supplies requiring stable component supply across industrial, medical, and portable electronics programs.

Supply support for LT1615IS5-1#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 acquired Linear Technology in 2017 and maintains its precision analog and power management portfolio with rigorous qualification standards.

The LT1615 family was developed specifically for space-constrained, battery-powered systems demanding micropower efficiency and wide-input-voltage flexibility - especially where 1V start-up and minimal external components are critical.

FAQ

What is the minimum input voltage required for LT1615IS5-1#TRPBF to start switching?

The LT1615IS5-1#TRPBF starts switching at 1.0V nominal input voltage, verified over temperature and process variation. This enables direct operation from deeply discharged single-cell batteries, including 1.0V–1.5V alkaline, NiMH, or zinc-air cells. Startup behavior is guaranteed per the Absolute Maximum Ratings table and confirmed in Typical Performance Characteristics graphs showing functional operation down to 1V across –40°C to 85°C.

Does LT1615IS5-1#TRPBF include built-in overvoltage or overtemperature protection?

The LT1615IS5-1#TRPBF does not integrate overvoltage or overtemperature shutdown circuitry. It relies on external feedback network design for output voltage limiting and thermal management via PCB copper area and ambient airflow. The device includes internal current-limit and adaptive off-time reduction under low-FB conditions to mitigate thermal stress during overload, but no dedicated thermal shutdown or output clamp is present.

Can LT1615IS5-1#TRPBF be used in SEPIC topology, and what external components are required?

Yes, LT1615IS5-1#TRPBF supports SEPIC operation, as documented in the Typical Applications section (Figure TA07). Required external components include two matched inductors (e.g., Murata LQH3C100K24), a Schottky diode (e.g., MBR0520), input/output ceramic capacitors (4.7µF and 10µF), and a feedback resistor divider. No additional ICs or compensation networks are needed - the same 400ns off-time control scheme applies.

What is the typical efficiency of LT1615IS5-1#TRPBF at 10mA load with 1.2V input and 3.3V output?

At 10mA load, 1.2V input, and 3.3V output, LT1615IS5-1#TRPBF achieves approximately 72% efficiency, based on the "2-Cell to 3.3V Converter Efficiency" curve (TA03a) scaled to 1.2V input per the device's characteristic curves. Efficiency remains above 70% from 1mA to 30mA under these conditions, enabled by 20µA quiescent current and low-loss 250mV V_CE(SAT).

Is LT1615IS5-1#TRPBF pin-compatible with LT1615IS5#TRPBF?

Yes, LT1615IS5-1#TRPBF is pin-compatible with LT1615IS5#TRPBF - both share identical ThinSOT-23 pinout (SW, GND, FB, SHDN, VIN), package dimensions, and footprint. The only functional difference is current limit (100mA vs. 350mA) and minimum input voltage (1.0V vs. 1.2V); no PCB redesign is needed when substituting between them in existing layouts.