LT3758EMSE - 100V Boost/Flyback/SEPIC Controller | ADI
N.º de pieza: LT3758EMSE ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $6.42 | $6,42 |
| 10 | $5.78 | $57,80 |
| 100 | $5.15 | $515,00 |
| 500 | $4.61 | $2.305,00 |
| 1.000 | $4.1 | $4.100,00 |
LT3758EMSE Descripción general
A DC/DC controller (also called a switching controller or SMPS controller) is an IC that drives an external power MOSFET or switch to convert one DC voltage to another using high-frequency switching and magnetic components. It sits in the power management hierarchy between a switching regulator (which integrates the power switch) and a fully integrated point-of-load (PoL) module. Unlike a linear regulator, a switching controller achieves high efficiency across wide VIN/VOUT ratios by storing energy in an inductor and releasing it at a different voltage, but requires careful PCB layout and external component selection.
Key features of the LT3758EMSE include a 5.5V to 100V input voltage range, programmable operating frequency from 100kHz to 1MHz set by an external resistor, optional external clock synchronization via the SYNC pin, 1µA typical shutdown quiescent current for battery-powered systems, and an internal 7.2V gate driver capable of driving standard N-channel MOSFETs. The novel FBX pin accepts feedback directly from a positive or negative output divider, eliminating the need for level-shifting circuitry in inverting converter topologies.
The LT3758EMSE uses current-mode control with a precision internal reference, providing excellent line and load regulation, cycle-by-cycle current limiting, and simple loop compensation. Demonstration circuit DC1342A from Analog Devices showcases the part in a 300kHz flyback converter delivering 3.3V/3A from an 18V to 75V input, validating its suitability for telecom and industrial bus voltage conversion.
Typical applications include 24V to 48V telecom bus converters, automotive 12V/24V battery-powered systems, isolated flyback power supplies for industrial sensors, and SEPIC converters for battery charging. The wide VIN range also makes it ideal for distributed power architectures fed from rectified 110V/220V AC lines.
When designing with the LT3758EMSE, ensure the input capacitor, power inductor, and current-sense resistor are sized for the worst-case VIN and load transients. The exposed pad must be soldered to a sufficiently large copper pour to keep junction temperature within the -40°C to +125°C operating range.
This page synthesizes distributor pricing, drop-in alternatives from the same Linear Technology/Analog Devices controller family, and practical design notes that go beyond the manufacturer datasheet to accelerate your evaluation.
Alternativas directas para LT3758EMSE — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con LT3758EMSE (mismo factor de forma y huella) — difiere en Package, RoHS Status, Topology, Control Mode, Input Voltage Range.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
LT3758IMSE#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LT3758HMSE#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LT3758EMSE#PBF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
LT3758AEMSE#PBF
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
LT3571EMSE#PBF
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
LT3758EMSE Valores máximos y características eléctricas
| Topología | Boost, Flyback, SEPIC, Inverting |
| Rango de tensión de entrada | 5.5 V to 100 V |
| Tensión de salida | Positive or Negative (isolation capable) |
| Número de salidas | 1 |
| Switching Frequency Range | 100 kHz to 1 MHz |
| Synchronization | Yes (SYNC pin, external clock) |
| Shutdown Quiescent Current | 1 µA typical |
| Control Method | Current-mode |
| Gate Driver Voltage | 7.2 V internal regulator |
| Encapsulado | MSOP-10 (EP) |
| Rango de temperatura de funcionamiento | -40 °C to +125 °C (E grade) |
| Tipo de montaje | Surface Mount |
| Nivel MSL | 1 |
| Lead Finish | Matte Tin (Pb-free) |
| Estado RoHS | Compliant (#PBF suffix) |
Configuración de pines de LT3758EMSE
| Pin 1 | RT — Timing resistor (sets switching frequency) |
| Pin 2 | SYNC — Synchronization input to external clock |
| Pin 3 | SHDN — Shutdown (active low) |
| Pin 4 | FBX — Feedback from positive or negative output divider |
| Pin 5 | VREF — Internal reference voltage output |
| Pin 6 | VIN — Input supply voltage |
| Pin 7 | GND — Ground |
| Pin 8 | SENSE — Current-sense input (inductor current) |
| Pin 9 | GATE — External MOSFET gate drive |
| Pin 10 | VC — Compensation node for error amplifier |
Aplicaciones típicas
LT3758EMSE es adecuado para 6 aplicacións: Telecom 48V Bus Converter, Automotive 12V/24V Battery-Powered Systems, Isolated Industrial Sensor Supply, Battery Charging Systems, Inverting Converter for LCD Bias, Distributed Power Architecture (DPA) Bus Converter.
Telecom 48V Bus Converter
The LT3758EMSE's 100V absolute maximum VIN comfortably accepts the 48V telecom bus (-36V to -75V when measured as positive-to-ground). In a typical flyback configuration, the LT3758EMSE drives an external 100V MOSFET to deliver isolated 12V/3A rails for base-station RF power amplifiers and line cards. The 1µA shutdown quiescent current preserves battery hold-up during AC mains loss, and the SYNC pin allows multiple converters to operate at a common clock to avoid beat-frequency noise.
Recomendado
Automotive 12V/24V Battery-Powered Systems
The 5.5V to 100V VIN range covers cold-cranking (down to 6V), nominal 12V, and load-dump transients (up to 80V) typical of automotive electrical environments. The LT3758EMSE in a boost topology can generate the 24V rail required for audio amplifiers from a 12V battery, while a SEPIC configuration charges 12V lead-acid backup batteries from a 24V truck bus. Its 1µA shutdown quiescent current is critical for body-control modules that must meet <100µA quiescent drain in key-off state.
Recomendado
Isolated Industrial Sensor Supply
In factory-floor sensor nodes requiring galvanic isolation (4-20mA loops, isolated RS-485, isolated gate drivers), the LT3758EMSE in flyback configuration provides the isolation barrier and primary-side regulation in a single IC. The novel FBX pin accepts feedback from a TL431 reference on the secondary side through an optocoupler, eliminating the level-shift circuitry that older controllers required. Industrial design wins include 24V-to-5V/1A isolated supplies for PLC digital inputs.
Recomendado
Battery Charging Systems
The LT3758EMSE in SEPIC topology accepts a wide input range (12V-72V from automotive or solar sources) and charges a stack of Li-ion cells with constant-current/constant-voltage (CC/CV) regulation. The low shutdown quiescent current (1µA) is essential for solar charge controllers that must preserve energy overnight, while the SYNC pin synchronizes the converter to an external clock to avoid interference with RF or audio circuits. Charge currents up to 5A are practical with a properly sized external MOSFET.
Recomendado
Inverting Converter for LCD Bias
The LT3758EMSE's FBX pin accepts a feedback divider directly from a negative output, eliminating the level-shift network required by older controllers for inverting topologies. This makes it ideal for generating the -5V to -15V bias rails required by TFT LCD panels from a single positive input supply. The 100kHz to 1MHz switching frequency allows designers to balance efficiency against audible noise requirements in display applications.
Recomendado
Distributed Power Architecture (DPA) Bus Converter
In intermediate bus architectures (IBA), the LT3758EMSE converts a 24V or 48V DC distribution bus to an intermediate voltage (typically 5V-12V) feeding multiple downstream point-of-load converters. Its 5.5V to 100V input range accepts rectified 110V/220V AC rails after PFC, eliminating the need for separate front-end converters. Wide frequency programming (100kHz to 1MHz) lets designers tune for the best efficiency/size trade-off in compact DPA modules.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para LT3758EMSE — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | LT3758IMSE#PBF | LT3758HMSE#PBF | LT3758EMSE#PBF | LT3758AEMSE#PBF | LT3571EMSE#PBF |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | MSOP-10 (EP) | MSOP-10 (EP) - same | MSOP-10 (EP) - same | MSOP-10 (EP) - same | MSOP-10 (EP) - same | MSOP-10 (EP) - same |
| Input Voltage Range | 5.5 V to 100 V | 5.5 V to 100 V | 5.5 V to 100 V | 5.5 V to 100 V | 5.5 V to 100 V | 2.5 V to 6 V |
| Switching Frequency Range | 100 kHz to 1 MHz | 100 kHz to 1 MHz | 100 kHz to 1 MHz | 100 kHz to 1 MHz | 100 kHz to 1 MHz | 500 kHz to 2 MHz |
| Topology | Boost, Flyback, SEPIC, Inverting | Boost, Flyback, SEPIC, Inverting | Boost, Flyback, SEPIC, Inverting | Boost, Flyback, SEPIC, Inverting | Boost, Flyback, SEPIC, Inverting | Boost, SEPIC (limited) |
| Shutdown Quiescent Current | 1 µA typical | 1 µA | 1 µA | 1 µA | 1 µA | 10 µA |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C | -40 °C to +125 °C |
| Sync Pin | Yes (external clock) | Yes | Yes | Yes | Yes | No |
Diferenciadores clave
- Wide 5.5V to 100V input range (frente a LT3571EMSE#PBF)
- Novel FBX pin supports positive and negative outputs (frente a LT3753IFE)
- 1 µA shutdown quiescent current (frente a LT3571EMSE#PBF)
Notas de diseño
The LT3758EMSE's MSOP-10 EP package dissipates gate-drive losses plus quiescent current through the exposed pad, which must be soldered to a continuous ground copper pour. For high-frequency (1 MHz) operation driving large MOSFET gates (Qg > 30 nC), size the copper pour to at least 1 square inch to keep junction-to-ambient thermal resistance around 40 °C/W. At 1 MHz with a 30 nC MOSFET at 7.2V gate drive, gate-drive losses alone reach ~220 mW; size the pour accordingly.
Keep the high-current loop (VIN capacitor → inductor → SENSE resistor → GND → back to VIN cap) as small and tight as physically possible. The SENSE resistor should be a low-inductance (Kelvin-connected) type placed directly at pin 8 with the gate trace routed away to avoid dv/dt coupling. Place the VREF bypass capacitor (typically 0.1 µF) immediately adjacent to pin 5 to filter switching noise on the reference.
Do not exceed the SENSE pin's absolute maximum rating (typically ±2V); transients during MOSFET turn-off can ring above the DC sense voltage. Add an RC snubber (typically 100 Ω + 1 nF) across the sense resistor if ringing exceeds 1.5× the programmed current-limit threshold. Also, ensure the FBX divider impedance is between 5 kΩ and 50 kΩ - higher values pick up switching noise, lower values load the reference excessively.
Información de cumplimiento
RoHS compliance and lead-free status apply to the LT3758EMSE#PBF suffix variant. The base LT3758EMSE without #PBF suffix is the older leaded variant; Analog Devices recommends migration to #PBF for new designs.
