LT8645SIV#PBF - 65V 8A Silent Switcher 2 Buck | Analog Devices
N.º de pieza: LT8645SIV#PBF ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $6.9098 | $6,91 |
| 10 | $0 | $0,00 |
| 100 | $0 | $0,00 |
| 500 | $0 | $0,00 |
| 1.000 | $0 | $0,00 |
LT8645SIV#PBF Descripción general
A synchronous buck converter is a DC-DC voltage regulator that uses high-side and low-side switching transistors to transfer energy from an input rail to a lower output rail through an inductor. The LT8645S belongs to the power-management hierarchy: DC-DC converter, synchronous buck regulator, switching regulator, and semiconductor. Its Silent Switcher 2 architecture integrates features intended to suppress switching-node energy and radiated emissions while supporting operation at high switching frequencies.
The LT8645S delivers up to 8A of continuous output current, accepts a broad input range reported by distributors as 3.4V to 65V, and provides an adjustable output beginning at 0.97V. Newark identifies the adjustable output capability and 3.4V-to-65V input range, while DigiKey describes the device as a positive, single-output, 8A synchronous buck regulator. These values make it suitable for reducing higher-voltage buses to lower rails for processors, communications equipment, sensors, and industrial control electronics.
The family is specifically engineered to minimize EMI emissions without sacrificing high-frequency operation. Distributed bypass-capacitor integration can simplify high-current layout and improve switching-node behavior compared with conventional layouts that rely entirely on external input bypass arrangements. The result is useful when the power supply must operate beside sensitive analog, RF, measurement, or communications circuitry while maintaining a compact 32-lead TQFN footprint.
Typical applications include 48V industrial power distribution, automotive and transportation power systems, GSM and communications infrastructure, and high-current embedded computing. The wide input range allows the regulator to sit directly behind a protected higher-voltage bus, while the adjustable output supports multiple point-of-load rails when paired with appropriate external components.
Designers should follow the manufacturer datasheet for the exact pinout, compensation settings, exposed-pad layout, switching-frequency selection, and recommended capacitor and inductor values. Thermal design is especially important at 8A because regulator efficiency and voltage conversion ratio determine dissipation even though the package provides an exposed pad for board-level heat spreading.
This page combines verified distributor specifications, package details, sourcing information, application guidance, and engineering design notes. It highlights the LT8645S as a high-current, low-EMI, wide-input buck regulator while avoiding unverified details that should be confirmed against the current Analog Devices datasheet before layout or production release.
Alternativas directas para LT8645SIV#PBF — 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 LT8645SIV#PBF (mismo factor de forma y huella) — difiere en Architecture, Operating Temperature Range, Package, Maximum Output Current, Output Voltage Range.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
LT8645SEV#PBF
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$5.18 / unidad
Ver hoja de datos →LT8645SJV-2#PBF
✅ Sustitución directa✓ En stock
$6.6 / unidad
Ver hoja de datos →LT8645S-2IV#PBF
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
LT8645SIV#PBF-TR
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
LT8645SEV#W
✅ Sustitución directa ⚠️ Especificaciones sin verificar📋 Alternativa de referencia (no en el catálogo)
LT8645SIV#PBF Valores máximos y características eléctricas
| Regulator Topology | Synchronous step-down buck regulator |
| Rango de tensión de entrada | 3.4V to 65V |
| Corriente de salida máxima | 8A |
| Minimum Adjustable Output Voltage | 0.97V |
| Configuración de salida | Single positive adjustable output |
| Frecuencia de conmutación | 1.95MHz |
| Architecture | Second-generation Silent Switcher 2 |
| Integrated Bypass Capability | Yes, integrated bypass capacitor |
| Encapsulado | 32-lead TQFN exposed pad |
| Package Footprint | 6mm x 4mm QFN-class footprint |
| Tipo de montaje | Surface mount |
| Rango de temperatura de funcionamiento | -40C to +125C |
| RoHS Compliance | Compliant for PBF-terminated versions |
| WEEE Compliance | Compliant for PBF-terminated versions |
| Automotive Controlled Manufacturing | Available in #W-suffix versions |
| Switching Node | SW |
Guía de configuración de pines de LT8645SIV#PBF 6mm x 4mm qfn-class footprint
Configuración de pines para LT8645SIV#PBF (encapsulado 6mm x 4mm qfn-class footprint). Este dispositivo de potencia presenta terminales de puerta, drenador y fuente. Para encapsulados no polarizados, consulte la hoja de datos del fabricante para conocer la orientación exacta del pin 1 y los detalles del footprint. Las aplicaciones habituales incluyen el diseño de fuentes de alimentación, el accionamiento de motores y la conmutación de cargas.
No hay datos detallados de patillaje disponibles para LT8645SIV#PBF.
Consulte la hoja de datos para ver la configuración completa de patillas.
Aplicaciones típicas
LT8645SIV#PBF es adecuado para 6 aplicacións: 48V Industrial Power Rails, Automotive Electrical Control Units, Communications Infrastructure Equipment, High-Current Embedded Processing Rails, Precision Measurement and Test Equipment, Low-EMI Point-of-Load Conversion.
48V Industrial Power Rails
The LT8645SIV#PBF suits 48V industrial systems that need a compact, high-current rail with reduced EMI. Its verified 3.4V-to-65V input range and 8A output capability provide the required voltage and current envelope for many controller, sensor, actuator, and communications loads. Place the regulator near the protected bus with low-inductance input routing, and use the exposed pad as a controlled thermal spreader. Silent Switcher 2 architecture helps simplify adjacent analog and communications circuitry, while the adjustable output down to 0.97V supports multiple rail requirements with appropriate feedback components.
Recomendado
Automotive Electrical Control Units
The LT8645SIV#PBF is appropriate for evaluating automotive ECU power conversion when the input transients remain within the verified 65V limit and the exact ordering variant meets program requirements. The 8A rating supports mixed digital loads, while Silent Switcher 2 targets electromagnetic-emission control in compact electronics. The verified Mouser datasheet notes that controlled-manufacturing versions carry a #W suffix; therefore, engineers should not assume the standard LT8645SIV#PBF is automatically automotive-qualified. Prototype with careful input protection, exposed-pad thermal management, and conducted-versus-radiated emissions testing.
Recomendado
Communications Infrastructure Equipment
The LT8645SIV#PBF fits communications infrastructure that converts a higher-voltage bus into a lower current-intensive rail for line cards, radios, and signal-processing electronics. Its 8A capability provides useful load margin, while the 1.95MHz switching architecture and integrated bypass functionality support compact layouts with controlled EMI. Keep the switching loop small and provide local high-frequency and bulk capacitance to preserve control-loop performance. For RF-adjacent systems, validate radiated emissions across operating states because compliance depends on board layout, filtering, shielding, and cable configuration as well as the regulator itself.
Recomendado
High-Current Embedded Processing Rails
The LT8645SIV#PBF can generate an adjustable low-voltage rail for processors, modules, and high-speed digital subsystems that require up to 8A from a higher-voltage supply. Its output begins at 0.97V, allowing configuration for low core voltages when external feedback and compensation support the target rail. The regulator's high-current switching design demands short copper paths, low-ESR input/output capacitors, and correct inductor selection. Treat the exposed pad as part of the thermal design rather than an optional copper feature, and verify startup, load transient, and dropout behavior across the complete input range.
Recomendado
Precision Measurement and Test Equipment
The LT8645SIV#PBF is useful in measurement and test electronics when a subsystem requires substantial current but must avoid adding significant EMI to sensitive analog channels. Silent Switcher 2 architecture is designed to reduce switching emissions, and the integrated bypass capability can support a compact implementation. Keep analog and digital return currents separated carefully, use star-point grounding where appropriate, and maintain short high-current switching paths. Emphasize thermal verification because noise performance and stability alone do not guarantee safe junction temperature at 8A. Validate the final board with conducted-emissions measurements rather than relying only on schematic simulation.
Recomendado
Low-EMI Point-of-Load Conversion
The LT8645SIV#PBF is effective as a point-of-load converter where a wide-input bus is present and the resulting rail must combine 8A capability with controlled switching emissions. Its adjustable output down to 0.97V permits programmed rails from low digital voltages to higher intermediate supplies. Designers should use the datasheet's recommended compensation, switching-frequency, and capacitor arrangements to preserve loop stability and Silent Switcher 2 behavior. The 32-lead TQFN exposed pad improves heat flow only when connected to a properly sized thermal plane, so power-loss calculations and copper area remain part of the selection process.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para LT8645SIV#PBF — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | LT8645SEV#PBF | LT8645SJV-2#PBF | LT8645S-2IV#PBF | LT8645SIV#PBF-TR | LT8645SEV#W |
|---|---|---|---|---|---|---|
| Package | 32-lead TQFN exposed pad | 32-lead TQFN exposed pad | 32-lead TQFN exposed pad | 32-lead TQFN exposed pad | 32-lead TQFN exposed pad | 32-lead TQFN exposed pad |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Regulator Topology | Synchronous step-down regulator | Synchronous step-down regulator | Synchronous step-down regulator | Synchronous step-down regulator | Synchronous step-down regulator | Synchronous step-down regulator |
| Maximum Output Current | 8A | 8A | 8A | 8A | 8A | 8A |
| Output Configuration | Adjustable, minimum 0.97V | Fixed-output variant | Fixed -2 output variant | Fixed -2 output variant | Adjustable, minimum 0.97V | Fixed-output automotive variant |
| EMI Architecture | Second-generation Silent Switcher 2 | Silent Switcher 2 family | Silent Switcher 2 family; bypass details differ | Silent Switcher 2 family | Second-generation Silent Switcher 2 | Silent Switcher 2 automotive version |
| Automotive Manufacturing | Not identified as #W automotive version | Not identified as #W | Not identified as #W | Not identified as #W | Not identified as #W | Controlled manufacturing for automotive applications |
Diferenciadores clave
- Higher verified switching frequency (frente a Generic 8A synchronous buck regulators)
- Integrated low-EMI architecture (frente a Generic 8A synchronous buck regulators)
- Wide input range with high output current (frente a Low-voltage-only 8A buck regulators)
- Compact exposed-pad thermal implementation (frente a Leaded high-current regulators)
Notas de diseño
Use the manufacturer's Silent Switcher 2 layout and follow the current LT8645S datasheet exactly; the supplied search data does not include individual pin names. Keep the high-current input loop, SW node, and exposed-pad connection exceptionally short to preserve the low-EMI behavior. The verified package uses a 6mm by 4mm QFN-class footprint, so confirm land pattern and thermal-via recommendations against the official mechanical drawing rather than relying on a generic QFN footprint.
Estimated thermal design requirement: use PD = (VIN - VOUT) × IOUT for an ideal first-order regulator-loss estimate before accounting for switching and conduction losses. For example, 12V input, 5V output, and 8A load implies approximately 56W, so an 8A rail does not necessarily mean every operating point is practical. Copper under the exposed pad, thermal vias, board area, ambient temperature, and copper weight must be evaluated using the package thermal data.
Do not assume that every LT8645S suffix is a drop-in substitute. The cross-reference discussion for LT8645SJV-2#PBF raises concerns about INTVCC and BST bypass capacitors, while IV, EV, and JV suffixes can represent adjustable or fixed-output choices. Before replacing an existing LT8645SIV#PBF, compare the exact pinout, bias-network requirements, switching frequency, output configuration, thermal limits, and PCB footprint.
Silent Switcher 2 reduces EMI but does not eliminate board-level compliance testing. Keep the converter away from sensitive analog inputs, use the smallest practical switching loop, maintain a continuous return path, and avoid routing SW copper beneath sensitive nodes. Validate radiated emissions, conducted emissions, load-transient behavior, and output ripple on final hardware because enclosure, cables, filtering, and grounding can materially change system-level results.
Información de cumplimiento
The verified Mouser datasheet states that parts ending in PBF are RoHS and WEEE compliant. It also states that controlled-manufacturing versions are designated with a #W suffix for automotive quality and reliability requirements; LT8645SIV#PBF itself is not explicitly identified as that automotive variant. REACH, halogen-free, and conflict-minerals evidence were not supplied.
