LT3791IFE#PBF - 60V 4-Switch Sync Buck-Boost LED Driver | ADI
料号： LT3791IFE#PBF ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $6.51 | $6.51 |
| 10 | $5.95 | $59.50 |
| 100 | $5.2 | $520.00 |
| 500 | $4.8 | $2,400.00 |
| 1,000 | $4.5 | $4,500.00 |
LT3791IFE#PBF 概述
A buck-boost LED driver controller is a power management IC that regulates current through an LED string by stepping up or stepping down the input voltage as needed. Unlike a simple buck or boost converter, the 4-switch topology allows seamless transition between modes, ensuring stable LED current even when the input voltage fluctuates around the output voltage. This makes it ideal for automotive, industrial, and architectural lighting where input voltage variations are common.
Key features include a wide 4.7V to 60V input range, output voltage up to 52V, and the ability to drive high-power LEDs with efficiency exceeding 95%. The controller integrates four external MOSFET drivers, supports spread spectrum for low EMI, and includes protection features such as overvoltage, overcurrent, and thermal shutdown. Its constant-frequency operation simplifies EMI filtering and allows synchronization to an external clock.
The LT3791 uses a current mode control architecture with a precision reference, enabling accurate LED current regulation. The forced-continuous mode ensures low output ripple and predictable operation across all load conditions. The device also features a low supply current of 4000uA, making it efficient for battery-powered applications.
Typical applications include automotive LED headlights, industrial high-bay lighting, architectural lighting, and general-purpose constant-current LED drivers. Its wide input range and buck-boost capability make it versatile for systems with varying supply voltages, such as those powered by batteries or solar panels.
When designing with the LT3791, ensure proper PCB layout with short, low-inductance paths for the switching nodes and adequate thermal management for the external MOSFETs. The exposed pad on the TSSOP-EP package should be soldered to a large copper area for heat dissipation.
直接替换替代料： LT3791IFE#PBF ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： LT3791IFE#PBF （相同外形与封装尺寸） ——差异在于 Dimming, Switching Frequency, Input Voltage Range, Operating Temperature Range.
快速对比工具——选择替代料号进行并排对比：
LT3791EFE#PBF
✅ 直接替换✓ 有现货
$10.76 / 个
查看数据手册 →LT3791HFE#PBF
✅ 直接替换📋 参考替代料（不在目录中）
LT3791IFE-1#PBF
✅ 直接替换📋 参考替代料（不在目录中）
LT3791EFE#TRPBF
✅ 直接替换✓ 有现货
$5.5 / 个
查看数据手册 →TPS92630
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
NCL30051
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
MAX16832
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LT3791IFE#PBF 最大额定值与电气特性
| 拓扑 | Buck-Boost |
| 输出数量 | 1 |
| 输入电压范围 | 4.7 V to 60 V |
| 输出电压范围 | Up to 52 V |
| 开关频率 | 200 kHz to 700 kHz |
| Dimming | Analog, PWM |
| 电源电流 | 4000 uA |
| 封装 | 38-TSSOP-EP |
| 安装方式 | SMD/SMT |
| 工作温度范围 | -40C to +125C |
| RoHS | Compliant |
| Series | LT3791 |
| Product Category | LED Lighting Drivers |
| Control Architecture | Current Mode |
| 同步整流 | Yes |
LT3791IFE#PBF 引脚配置
| 引脚 1 | BOOST1 — Bootstrap for top FET 1 |
| 引脚 2 | TG1 — Top gate drive 1 |
| 引脚 3 | SW1 — Switch node 1 |
| 引脚 4 | BG1 — Bottom gate drive 1 |
| 引脚 5 | VIN — Input supply |
| 引脚 6 | VIN — Input supply |
| 引脚 7 | BG2 — Bottom gate drive 2 |
| 引脚 8 | SW2 — Switch node 2 |
| 引脚 9 | TG2 — Top gate drive 2 |
| 引脚 10 | BOOST2 — Bootstrap for top FET 2 |
| 引脚 11 | VOUT — Output voltage sense |
| 引脚 12 | VOUT — Output voltage sense |
| 引脚 13 | SENSE+ — Positive current sense |
| 引脚 14 | SENSE- — Negative current sense |
| 引脚 15 | CTRL — Current control input |
| 引脚 16 | PWM — PWM dimming input |
| 引脚 17 | SS — Soft-start |
| 引脚 18 | FREQ — Frequency set |
| 引脚 19 | SYNC — Synchronization input |
| 引脚 20 | MODE — Mode select |
| 引脚 21 | VREF — Reference output |
| 引脚 22 | FB — Feedback |
| 引脚 23 | VC — Compensation |
| 引脚 24 | OVP — Overvoltage protection |
| 引脚 25 | UVLO — Under-voltage lockout |
| 引脚 26 | RUN — Enable |
| 引脚 27 | GND — Ground |
| 引脚 28 | GND — Ground |
| 引脚 29 | GND — Ground |
| 引脚 30 | GND — Ground |
| 引脚 31 | GND — Ground |
| 引脚 32 | GND — Ground |
| 引脚 33 | GND — Ground |
| 引脚 34 | GND — Ground |
| 引脚 35 | GND — Ground |
| 引脚 36 | GND — Ground |
| 引脚 37 | GND — Ground |
| 引脚 38 | GND — Ground |
典型应用
LT3791IFE#PBF 适用于 6 应用s: Automotive LED Headlights, Industrial High-Bay Lighting, Architectural Lighting, Battery-Powered LED Lighting, Solar-Powered Street Lighting, General-Purpose Constant-Current LED Driver.
Automotive LED Headlights
The LT3791IFE#PBF is ideal for automotive LED headlights due to its wide 4.7V to 60V input range, which accommodates load-dump and cold-crank conditions. Its 4-switch buck-boost topology maintains constant LED current even when battery voltage fluctuates above or below the LED string voltage. The controller supports PWM dimming for adaptive driving beams and has a low 4000uA supply current for efficiency. With output up to 52V, it can drive multiple high-power LEDs in series, ensuring uniform brightness. Its robust protection features, including overvoltage and thermal shutdown, enhance reliability in harsh automotive environments.
推荐
Industrial High-Bay Lighting
For industrial high-bay lighting, the LT3791IFE#PBF provides efficient constant-current regulation for LED arrays with input voltages from 24V to 48V. Its buck-boost capability ensures stable light output even with long cable runs causing voltage drops. The adjustable 200kHz-700kHz switching frequency allows optimization for EMI and efficiency, crucial in industrial environments. The controller's analog dimming enables simple 0-10V dimming interfaces, while PWM dimming supports high-frequency dimming for advanced lighting control. Its wide temperature range (-40C to +125C) suits unheated warehouses and outdoor installations.
推荐
Architectural Lighting
The LT3791IFE#PBF excels in architectural lighting where precise current control and dimming are essential. Its 4-switch buck-boost topology allows operation from a wide range of supply voltages, accommodating both 12V and 24V systems. The controller supports both analog and PWM dimming, enabling smooth dimming curves for aesthetic lighting effects. With output voltage up to 52V, it can drive long LED strips or multiple fixtures in series. The constant-frequency operation ensures predictable EMI, simplifying compliance with lighting standards. Its small 38-TSSOP-EP package fits compact luminaire designs.
推荐
Battery-Powered LED Lighting
In battery-powered LED lighting, the LT3791IFE#PBF's wide input range (4.7V to 60V) allows operation from various battery chemistries, including Li-ion and lead-acid. Its buck-boost topology maintains constant LED current as the battery discharges, ensuring consistent brightness. The low 4000uA supply current minimizes battery drain, extending runtime. The controller's high efficiency (up to 95%) reduces heat generation, important for portable designs. PWM dimming allows brightness control without wasting power, making it suitable for flashlights, lanterns, and portable work lights.
推荐
Solar-Powered Street Lighting
The LT3791IFE#PBF is well-suited for solar-powered street lighting, where input voltage from solar panels varies widely with sunlight intensity. Its 4.7V to 60V input range handles the output of solar panels, and the buck-boost topology ensures constant LED current regardless of panel voltage. The controller's high efficiency maximizes energy harvest from the solar panel, and its low supply current reduces standby power. With output up to 52V, it can drive high-power LEDs used in streetlights. The wide temperature range and robust protection make it reliable for outdoor installations.
推荐
General-Purpose Constant-Current LED Driver
As a general-purpose constant-current LED driver, the LT3791IFE#PBF offers flexibility for a wide range of LED applications, from signage to decorative lighting. Its adjustable frequency and dimming options allow designers to tailor performance to specific needs. The 4-switch buck-boost topology eliminates the need for separate buck and boost converters, simplifying design and reducing component count. The controller's current mode architecture provides stable operation and fast transient response. Its 38-TSSOP-EP package is suitable for space-constrained designs, and the wide input range makes it adaptable to various power sources.
推荐
推荐产品汇总
工程参考数据： LT3791IFE#PBF ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | LT3791EFE#PBF | LT3791HFE#PBF | LT3791IFE-1#PBF | TPS92630 |
|---|---|---|---|---|---|
| Package | 38-TSSOP-EP | 38-TSSOP-EP | 38-TSSOP-EP | 38-TSSOP-EP | 38-TSSOP-EP |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Texas Instruments |
关键差异点
- Wide input voltage range of 4.7V to 60V （对比 TPS92630)
- 4-switch synchronous buck-boost topology （对比 MAX16832)
- Adjustable frequency up to 700kHz （对比 NCL30051)
设计说明
For the LT3791IFE#PBF, ensure the switching nodes (SW1, SW2) have minimal trace length and area to reduce parasitic inductance and EMI. Use a solid ground plane and place the input and output capacitors close to the VIN and VOUT pins. The exposed pad (pin 38) should be soldered to a large copper area for thermal dissipation. Follow the layout guidelines in the datasheet for optimal performance.
The LT3791IFE#PBF itself dissipates minimal power, but the external MOSFETs and inductor generate significant heat in high-power LED applications. Ensure adequate heatsinking for the MOSFETs and use a PCB with sufficient copper weight (2oz or more) for the power path. The TSSOP-EP package's exposed pad should be connected to a thermal via array to the ground plane to keep the controller cool.
A common pitfall is improper bootstrap capacitor selection for the top FETs. Use a 0.1uF ceramic capacitor with low ESR for BOOST1 and BOOST2. Also, ensure the sense resistor is placed correctly between SENSE+ and SENSE- to avoid ground noise. Do not exceed the absolute maximum ratings on any pin, and verify the UVLO resistor divider to prevent unintended shutdown.
合规信息
RoHS compliant per Analog Devices product page. AEC-Q100 qualification not specified; for automotive, consider LT3791HFE#PBF or verify with manufacturer.
