Analog Devices Inc. LT8570IMS8E-1#TRPBF

Overview

LT8570IMS8E-1#TRPBF from Analog Devices (formerly Linear Technology) is a 0.25A, 65V monolithic PWM DC/DC converter IC optimized for boost, SEPIC, and inverting topologies in space-constrained industrial and portable power supplies. It features adjustable 200kHz–1.5MHz switching frequency, integrated soft-start, synchronization capability, and user-configurable undervoltage lockout - enabling reliable bias generation for TFT-LCD and VFD displays operating from 2.55V–40V input rails.

For engineers reviewing the LT8570IMS8E-1#TRPBF datasheet, LT8570IMS8E-1#TRPBF pinout, LT8570IMS8E-1#TRPBF application, or LT8570IMS8E-1#TRPBF equivalent, this page delivers verified technical context, exact pin functions, real-world topology configurations, thermal performance data, and validated alternative options - all grounded in the official Linear Technology LTC8570-1 datasheet (Rev. FA) and Analog Devices product documentation.

Technical Context

The LT8570IMS8E-1#TRPBF implements constant-frequency current-mode control with internal slope compensation to prevent subharmonic oscillation above 50% duty cycle. Its dual-path feedback architecture supports both noninverting (1.204V reference) and inverting (3mV reference) configurations via the FBX pin, eliminating external op-amps in polarity-reversal designs.

It integrates a 65V NPN power switch with 250mV V_CE(SAT) at 0.2A, frequency foldback during soft-start (1/6 nominal f_OSC), and high-gain SHDN pin circuitry accepting slowly ramping enable signals. The device operates across –40°C to +125°C junction temperature and supports thermal shutdown at ~165°C with automatic restart below ~160°C.

Key Specifications

Pinout & Package

LT8570IMS8E-1#TRPBF is housed in an 8-lead plastic MSOP package (MS8E) with exposed pad (Pin 9 = GND). The thermally enhanced design achieves θ_JA = 35–40°C/W and requires soldering the exposed pad directly to the PCB ground plane for optimal thermal performance and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC3531EMS8E#TRPBF and MAX17504ATP+T, the LT8570IMS8E-1#TRPBF uniquely combines 65V switch rating, inverting/SEPIC/boost configurability, programmable UVLO, and synchronization in an MSOP-8 package - making it optimal for compact, multi-topology bias supplies where input voltage range and startup control are critical.

Availability

LT8570IMS8E-1#TRPBF is available at Aetrix Electronics and suitable for TFT-LCD bias supplies, VFD display power, and GPS receiver local power requiring stable component supply, long-term lifecycle support, and guaranteed RoHS-compliant sourcing.

Supply support for LT8570IMS8E-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 full technical and manufacturing continuity for the LT® product family. Linear Technology pioneered high-performance analog ICs with emphasis on power management innovation.

The LT8570/LT8570-1 product line was designed specifically for compact, high-voltage DC/DC bias generation in display, telecom, and instrumentation systems - emphasizing topology flexibility, robust protection, and ease of use in thermally constrained layouts.

FAQ

What topology configurations does the LT8570IMS8E-1#TRPBF support?

The LT8570IMS8E-1#TRPBF supports three distinct DC/DC topologies: boost (step-up), SEPIC (input can be above, equal to, or below output), and inverting (negative output). Configuration is determined solely by external component connections - no mode-select pins or internal registers are required. The FBX pin automatically adapts its reference (1.204V for noninverting, 3mV for inverting) based on external resistor biasing, enabling seamless reconfiguration without changing the LT8570IMS8E-1#TRPBF itself.

How is the output voltage set on the LT8570IMS8E-1#TRPBF?

The LT8570IMS8E-1#TRPBF uses a single feedback resistor (R_FBX) from V_OUT to the FBX pin to set output voltage. For boost or SEPIC (noninverting) operation, R_FBX = (V_OUT − 1.204V) / 83.3µA. For inverting operation, R_FBX = (V_OUT + 3mV) / 83.3µA. This eliminates traditional resistor dividers and reduces component count. The LT8570IMS8E-1#TRPBF's internal current-source-based feedback ensures accuracy independent of supply voltage variations.

What is the purpose of the SYNC pin on the LT8570IMS8E-1#TRPBF?

The SYNC pin on the LT8570IMS8E-1#TRPBF allows external clock synchronization to eliminate beat frequencies and reduce EMI in multi-converter systems. When driven with a logic-level clock (high >1.3V, low <0.4V), the LT8570IMS8E-1#TRPBF locks its switching frequency to the external source. If SYNC is pulled below 0.4V, the device reverts to its internal free-running oscillator set by the RT resistor. This feature is essential for noise-sensitive applications like GPS receivers or audio subsystems where uncorrelated switching noise must be avoided.

Does the LT8570IMS8E-1#TRPBF include thermal protection?

Yes, the LT8570IMS8E-1#TRPBF includes fully integrated thermal shutdown protection that activates at approximately 165°C junction temperature. When triggered, the internal SR2 latch disables switching and holds the device in shutdown until the die cools to ~160°C, at which point a full soft-start sequence is initiated. This protection safeguards both the LT8570IMS8E-1#TRPBF and external components during overload, poor heatsinking, or ambient temperature excursions - without requiring external thermal sensors or circuitry.

Can the LT8570IMS8E-1#TRPBF operate from a 2.55V input?

Yes, the LT8570IMS8E-1#TRPBF is fully specified to operate from 2.55V up to 40V input, making it suitable for single-cell Li-ion (2.7–4.2V), 3.3V logic rails, and wide-range industrial inputs. Its internal bias circuitry remains functional at 2.55V, and the 0.25A current limit and 65V switch ensure reliable operation even at minimum VIN. This capability is critical for cold-crank automotive or battery-backed applications where input may dip below 3V - a key differentiator of the LT8570IMS8E-1#TRPBF versus many competing 3V-minimum converters.