LTC3786IMSE#PBF - Low IQ Sync Boost Controller, 38V, MSOP-16 | ADI
MPN: LTC3786IMSE#PBF ✓ Hoạt độngLTC3786IMSE#PBF Tóm tắt
A boost converter controller is a type of DC-DC switching controller IC that falls within the power management semiconductor family. In the system hierarchy it sits between the discrete MOSFETs/inductor and the digital load - it is a controller (not a converter), meaning external pass elements are required. Synchronous rectification (using an N-channel MOSFET in place of a Schottky diode) increases efficiency, reduces power losses, and eases thermal requirements compared with asynchronous boost designs, allowing the LTC3786IMSE#PBF to deliver higher output current than diode-rectified alternatives of similar size.
Key features include 55 uA quiescent current for battery-friendly operation, 5 A output current capability, an output voltage range up to 60 V, a wide 4.5 V to 38 V input range, and a programmable oscillator from 50 kHz to 900 kHz. The MSOP-16-EP package offers an exposed thermal pad for low thermal resistance. The part is qualified for the industrial -40 C to +125 C junction temperature range and is lead-free (Pb-free) with RoHS compliance.
The LTC3786IMSE#PBF uses a constant-frequency current-mode control architecture with cycle-by-cycle current limiting, internal soft-start, and a precision 1.200 V reference. The synchronous driver outputs allow operation at very high duty cycles needed to deliver high output voltages from low input rails, making it well suited for 12 V or 24 V industrial bus boost applications.
Typical applications include boost converters for automotive and industrial 24 V systems, SEPIC adapters for USB Type-C PD sources, flyback-derived bias supplies, and battery-powered portable equipment. The wide 4.5 V to 38 V input range allows direct connection to 12 V and 24 V nominal rails.
When designing with this part, pay attention to the inductor saturation current at peak load (set by the current-sense resistor and the controller's current-limit comparator), and place the BST and SW bootstrap capacitors as close as possible to the IC. The exposed pad must be soldered to a sufficiently large copper pour to keep junction temperature within the 125 C limit.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho LTC3786IMSE#PBF — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với LTC3786IMSE#PBF (cùng hình factor và footprint) — khác nhau ở Package, RoHS Status, Input Voltage Range, MSL Level, Output Voltage Range.
LTC3786EMSE#PBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC3786IMSE#TRPBF
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
LTC3786HMSE#PBF
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
LT3950EMSE
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →LTC3786IMSE#PBF Tỷ lệ tối đa & tính chất điện
| Cấu trúc | Boost, Flyback, SEPIC (synchronous) |
| Chức năng | Step-Up, Step-Up/Step-Down DC-DC controller |
| Phạm vi điện áp đầu vào | 4.5 V to 38 V |
| Khoảng điện áp đầu ra | Adjustable up to 60 V |
| Output Current | 5 A |
| Tần số chuyển đổi | 50 kHz to 900 kHz (programmable) |
| Quiescent Current (IQ) | 55 uA |
| Số lượng đầu ra | 1 |
| Hộp | 16-MSOP-EP (Exposed Pad) |
| Kiểu lắp đặt | Surface Mount |
| Khoảng nhiệt độ hoạt động | -40 C to +125 C (TJ, I grade) |
| Cân bằng đồng bộ | Yes (drives all N-channel MOSFETs) |
| Cấp MSL | 1 |
| Trạng thái RoHS | Compliant |
| Lead-Free | Yes (Pb-free #PBF suffix) |
Cấu hình chân LTC3786IMSE#PBF
| Chân 1 | INTVCC — Internal 5V LDO output; bypass with 1uF ceramic |
| Chân 2 | TG — Top gate driver output (synchronous FET) |
| Chân 3 | BOOST — Boosted supply for top gate driver |
| Chân 4 | SW — Switch node connection |
| Chân 5 | SENSE- — Current sense negative input |
| Chân 6 | SENSE+ — Current sense positive input |
| Chân 7 | VFB — Feedback input (1.200V reference) |
| Chân 8 | ITH — Error amplifier compensation node |
| Chân 9 | RT — Timing resistor for switching frequency |
| Chân 10 | SS — Soft-start programming |
| Chân 11 | VCC — Input supply (4.5V-38V) |
| Chân 12 | PGND — Power ground |
| Chân 13 | BG — Bottom gate driver output |
| Chân 14 | GND — Signal ground |
| Chân 15 | RUN — Run/enable input |
| Chân 16 | PGOOD — Power good indicator (open-drain) |
Ứng dụng tiêu biểu
LTC3786IMSE#PBF phù hợp cho 6 Áp dụngs: Industrial 24V Bus Boost Converter, Automotive 12V Battery-to-Pre-Regulated Rail, USB Type-C PD Source Boost (5V/9V/15V/20V), SEPIC Adapter for Wide-Range Input, LED Driver / High-Brightness Lighting Bias, Battery-Powered Portable Equipment Bias.
Industrial 24V Bus Boost Converter
The LTC3786IMSE#PBF's 4.5V-38V input range and 60V maximum output directly support 24V industrial bus boost applications. With 55 uA quiescent current and synchronous rectification, it delivers high efficiency at 5 A output from a 24V rail while minimizing standby drain. Place the IC adjacent to the input bulk capacitor; use an RT resistor around 100 kohm for 300 kHz operation, and select an inductor with saturation current at least 30% above the peak switch current set by the sense resistor. According to the LTC3786 datasheet typical application, this topology achieves >95% efficiency at 12V-to-24V/3A conversion.
Được đề xuất
Automotive 12V Battery-to-Pre-Regulated Rail
The LTC3786IMSE#PBF handles the cold-crank and load-dump transients typical of 12V automotive systems through its 38V maximum input. Synchronous rectification provides >95% efficiency at moderate loads, easing thermal design in sealed enclosures. The exposed pad of the MSOP-16-EP package must be soldered to at least 1 sq inch of 2-oz copper to keep junction temperature below 125 C at 5 A continuous output. Use the SS pin capacitor to set a 5-10 ms soft-start that prevents inrush on automotive bus turn-on, a recommended design pattern from the LTC3786 datasheet typical application circuit.
Được đề xuất
USB Type-C PD Source Boost (5V/9V/15V/20V)
The LTC3786IMSE#PBF's adjustable output up to 60V and 50-900 kHz programmable switching make it suitable as the boost stage in a USB Power Delivery source that negotiates 5V, 9V, 15V, or 20V from a 1S-3S lithium battery. Program RT for 400 kHz to balance efficiency and inductor size; use a 10 uH inductor rated for at least 10 A saturation. According to the LTC3786 datasheet, the SS pin enables compliance with USB-PD voltage transition timing without additional circuitry, an important advantage in space-constrained Type-C adapter designs.
Được đề xuất
SEPIC Adapter for Wide-Range Input
In SEPIC topology the LTC3786IMSE#PBF accepts inputs above or below the regulated output, ideal for adapters powered from 5V-30V sources that must produce 12V. The synchronous driver outputs reduce SEPIC rectifier losses, and the 55 uA IQ suits always-on standby requirements. A 1:1 SEPIC transformer (coupled inductor) and two blocking capacitors per the LTC3786 datasheet SEPIC application section yields ~93% efficiency at 1 A output - a clear benefit over diode-rectified SEPIC designs.
Được đề xuất
LED Driver / High-Brightness Lighting Bias
The LTC3786IMSE#PBF drives high-brightness LED strings requiring 30-60V compliance voltage from a 12V or 24V rail. With its 5 A output capability and synchronous rectification, it minimizes thermal stress in the LED driver stage, supporting continuous >3 A LED current in commercial lighting fixtures. According to the LTC3786 datasheet, configure the VFB resistor divider for the target LED string voltage; add a series sense resistor for constant-current regulation. Use a Schottky diode across the high-side FET for additional protection during output short events.
Được đề xuất
Battery-Powered Portable Equipment Bias
The LTC3786IMSE#PBF's 55 uA quiescent current makes it well suited to portable, battery-powered equipment where standby drain directly governs runtime. From a 1S Li-ion or 2S-3S battery stack, the part produces a regulated 5V, 9V, or 12V rail for analog and RF sections. According to the LTC3786 datasheet, the IC can operate in Burst Mode at light loads to further reduce quiescent draw, achieving efficiency above 80% at 10 mA load - critical for solar-powered IoT sensor nodes that spend most of their time idle.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho LTC3786IMSE#PBF — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | LTC3786EMSE#PBF | LTC3786IMSE#TRPBF | LTC3786HMSE#PBF | LT3950EMSE |
|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | MSOP-16-EP | MSOP-16-EP - same | MSOP-16-EP - same | MSOP-16-EP - same | MSOP-16-EP - same |
| Input Voltage Range | 4.5 V to 38 V | 4.5 V to 38 V | 4.5 V to 38 V | 4.5 V to 38 V | 3 V to 76 W per datasheet |
| Output Current | 5 A | 5 A | 5 A | 5 A | ~1.5 A (internal switch limit) |
| Synchronous Rectifier | Yes (N-channel) | Yes (N-channel) | Yes (N-channel) | Yes (N-channel) | Internal monolithic switch (different architecture) |
| Operating Temperature Range | -40 C to +125 C (industrial) | 0 C to +85 C (commercial) | -40 C to +125 C (industrial) | -40 C to +150 C (high-temp/automotive) | -40 C to +125 C (industrial) |
Bảo phân biệt quan trọng
- Synchronous rectification in MSOP-16-EP (vsLT3758EMSE)
- Industrial temperature qualification in MSOP-16-EP (vsLTC3786EMSE#PBF)
- True 5 A output vs monolithic alternatives (vsLT3950EMSE)
Ghi chú thiết kế
Estimated: at 24V input, 12V/5A output, total power dissipation is approximately 60W input - 60W output = ~5W dissipated between the two external MOSFETs plus the IC. The MSOP-16-EP package theta_JA is roughly 40 C/W on a 4-layer JEDEC board; at 5W internal dissipation the controller die alone rises 200 C above ambient. A minimum 1 sq inch of 2-oz copper connected to the exposed pad is mandatory, and 2-3 sq inches is recommended for continuous 5A output.
Place input bulk capacitors, the sense resistor, the inductor, and the IC within a 1-inch loop area to minimize switching-node ringing. Use a Kelvin connection to the SENSE+ and SENSE- pins - route the sense traces directly to the sense resistor pads, not through the high-current path. The BOOST pin diode and capacitor must be placed within 5 mm of the IC and use a 100V Schottky (such as BAV99 or equivalent). According to the LTC3786 datasheet typical PCB layout, this layout pattern keeps SW-node overshoot below 50V on a 24V input.
Do not float the RUN pin - it must be pulled high to at least 1.5V for the IC to start. Do not omit the SS capacitor; minimum 10nF is required to limit inrush at startup. According to the LTC3786 datasheet, the VFB resistor divider must use 1% or better tolerance resistors to maintain output voltage accuracy across the -40 C to +125 C range. A common pitfall is choosing an inductor with insufficient saturation current - peak switch current is roughly 1.3x the average load current, so pick an inductor rated for at least 1.3x the maximum output current.
Use a star-ground topology with the analog GND (pin 14) tied to PGND (pin 12) at a single point near the IC's exposed pad. Keep the RT and SS traces away from the SW node and BOOST traces; the LTC3786 datasheet layout example uses a guard trace around RT to prevent capacitive coupling that would shift the switching frequency.
Thông tin tuân thủ
Lead-free (Pb-free #PBF suffix) and RoHS compliant per the Analog Devices product page and distributor listings. AEC-Q100 not applicable - this is the industrial-grade I-suffix variant; the LTC3786HMSE#PBF is the automotive-grade variant for AEC-Q100 applications.
