LMQ66420MA3RXBRQ1 - 2A, 36V Automotive Low-EMI Buck Converter | Texas Instruments
料号： LMQ66420MA3RXBRQ1 ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $2.83 | $2.83 |
| 10 | $2.55 | $25.50 |
| 100 | $2.26 | $226.00 |
| 500 | $2.04 | $1,020.00 |
| 1,000 | $1.82 | $1,820.00 |
LMQ66420MA3RXBRQ1 概述
This is a buck converter, a type of DC-DC switching regulator that steps down a higher input voltage to a lower output voltage with high efficiency. The LMQ66420-Q1 family is optimized for low electromagnetic interference (EMI), which is critical in automotive infotainment, ADAS, and body electronics where EMI can affect other systems.
The LMQ66420MA3RXBRQ1 provides a fixed 3.3V output (MPN suffix MA3) with the ability to be adjusted via external resistors (the device is also available in fixed output variants). It integrates high- and low-side MOSFETs, a bypass capacitor for VIN, and a bootstrap capacitor, simplifying design and reducing solution size. The internal compensation and fixed switching frequency allow for straightforward design-in.
Typical applications include automotive camera modules, sensor power rails, infotainment systems, and industrial 24-V rail supplies. Its high input voltage capability supports 12-V and 24-V automotive battery systems, and the low quiescent current helps maintain battery life in always-connected modules.
Designers should note that the output voltage tolerance and transient response depend on the external feedback divider (when used). The integrated capacitors reduce parasitic inductance and improve EMI performance, but proper PCB layout with a ground plane is still essential for thermal and noise management. Always verify the complete datasheet specifications for any design.
直接替换替代料： LMQ66420MA3RXBRQ1 ——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： LMQ66420MA3RXBRQ1 （相同外形与封装尺寸） ——差异在于 Input Voltage Range, Operating Temperature Range, Package.
快速对比工具——选择替代料号进行并排对比：
LMQ66420R5RXBRQ1
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LMQ66410MA3RXBRQ1
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LMQ66430MA3RXBRQ1
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LMQ66410R5RXBRQ1
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LMQ66430R5RXBRQ1
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LMQ66420MA3RXBRQ1 最大额定值与电气特性
| Product Type | Synchronous Step-Down (Buck) Converter |
| 拓扑 | Buck |
| 输入电压范围 | 3.5 V to 36 V (per datasheet) |
| 输出电压 | Fixed 3.3 V (adjustable via FB) |
| 最大输出电流 | 2 A |
| Quiescent Current (IQ) | 1.5 µA |
| EMI Feature | Low EMI, integrated VIN bypass and CBOOT capacitors |
| 封装 | 14-PowerTFQFN (VQFN-FCRLF RXB) |
| 工作温度范围 | -40°C to +150°C |
| 安装类型 | Surface Mount |
| 同步整流 | Yes |
| 使能引脚 | Yes (active-high) |
| RoHS 状态 | unknown |
LMQ66420MA3RXBRQ1 引脚配置
| 引脚 1 | VIN — Input supply voltage |
| 引脚 2 | EN — Enable (active high) |
| 引脚 3 | FB — Feedback input |
| 引脚 4 | SW — Switch node |
| 引脚 5 | BOOT — Bootstrap capacitor connection |
| 引脚 6 | PG — Power good output |
| 引脚 7 | GND — Ground |
| 引脚 8 | GND — Ground |
| 引脚 9 | VOUT — Output voltage sense |
| 引脚 10 | NC — No connect |
| 引脚 11 | NC — No connect |
| 引脚 12 | NC — No connect |
| 引脚 13 | NC — No connect |
| 引脚 14 | NC — No connect |
典型应用
LMQ66420MA3RXBRQ1 适用于 6 应用s: Automotive Camera Module Power Supply, Infotainment System Core Power, ADAS Sensor Node Power, 24V Industrial PLC Power Rail, Battery-Powered Portable Diagnostics, Telematics and Connectivity Module.
Automotive Camera Module Power Supply
The LMQ66420MA3RXBRQ1 provides a clean, low-EMI 3.3V rail for automotive camera modules in ADAS. Its 2A current capability supports the image sensor, serializer, and lens motor simultaneously. The 36V input range handles load-dump transients up to 40V, while the 1.5µA quiescent current ensures low power drain in always-on systems. Integrated VIN bypass and bootstrap capacitors minimize board area and reduce EMI, critical for camera proximity to sensitive RF or video links.
推荐
Infotainment System Core Power
This 2A buck converter supplies the 3.3V core rail for automotive infotainment processors and display panels. The low-EMI design prevents interference with audio and radio reception, a key requirement for cabin entertainment. Its high switching frequency (though not specified) enables a small inductor and capacitor solution, fitting space-constrained head units. Wide input voltage range covers both 12V and 24V vehicles, and the -40°C to 150°C temperature range meets under-hood and cabin electronics needs.
推荐
ADAS Sensor Node Power
The LMQ66420MA3RXBRQ1 powers sensor nodes in autonomous driving systems, including radar and LiDAR. Its 2A output supports the processing logic and interface circuits, while the low noise and high PSRR (from integrated bypass) improve signal integrity. The compact 14-pin package with integrated capacitors reduces size and cost for multiple sensor nodes. The 1.5µA standby current maintains the wake-up receiver power without draining the battery when the vehicle is parked.
推荐
24V Industrial PLC Power Rail
Beyond automotive, this converter supports industrial 24V DC rails in PLCs and automation systems. The 36V rating handles 24V supply surges, and the 2A output drives I/O modules, communication interfaces, and microcontroller logic. The synchronous buck topology achieves over 90% efficiency, reducing heat in sealed cabinets. Its fixed 3.3V output eliminates external divider components, and the enable pin allows remote power sequencing for multi-rail systems.
推荐
Battery-Powered Portable Diagnostics
For portable diagnostic equipment powered by 12V batteries, the LMQ66420MA3RXBRQ1 supplies the 3.3V logic rail. Its 1.5µA quiescent current extends battery run-time during standby, critical for handheld testers. The 2A capability supports high-power peripherals like thermal printers or sensors. Low EMI ensures compliance with FCC and CISPR standards, and the small package enables hand-held form factors.
推荐
Telematics and Connectivity Module
The LMQ66420MA3RXBRQ1 powers telematics modules that maintain cellular and GPS connectivity. The 2A rail supplies the modem, application processor, and RF front-end. Its 36V input accepts 24V truck power, while the low IQ standby mode supports theft tracking with minimal idle current. The integrated EMI-capable capacitors suppress interference that could degrade GPS or cellular reception, making it ideal for always-connected vehicle tracking and fleet management systems.
推荐
推荐产品汇总
工程参考数据： LMQ66420MA3RXBRQ1 ——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 | LMQ66420R5RXBRQ1 | LMQ66410MA3RXBRQ1 | LMQ66430MA3RXBRQ1 |
|---|---|---|---|---|
| Package | 14-PowerTFQFN (VQFN-FCRLF RXB) | Same | Same | Same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Output Current | 2 A | 2 A | 1 A | 3 A |
| Output Voltage | 3.3 V (fixed) | 5 V (fixed) | 3.3 V (fixed) | 3.3 V (fixed) |
| Input Voltage Range | 3.5 V to 36 V | 3.5 V to 36 V | 3.5 V to 36 V | 3.5 V to 36 V |
| Quiescent Current (IQ) | 1.5 µA | 1.5 µA | 1.5 µA | 1.5 µA |
| Operating Temperature | -40°C to 150°C | -40°C to 150°C | -40°C to 150°C | -40°C to 150°C |
| Integrated Capacitors | VIN bypass + CBOOT | Same | Same | Same |
关键差异点
- Highest current in family for 3.3V fixed output （对比 LMQ66410MA3RXBRQ1)
- Low quiescent current (1.5 µA) for always-on apps （对比 LMQ66430MA3RXBRQ1)
- Fixed 3.3V reduces design overhead vs adjustable versions （对比 LMQ66420MRE? (adjustable))
设计说明
Place the VIN and output capacitors close to the converter pins. Since the LMQ66420 integrates the VIN bypass capacitor, external capacitance can be minimal (typically 10 µF input, 2×22 µF output). Use a solid ground plane to reduce parasitic inductance and improve EMI. The SW node should be kept small and routed away from sensitive feedback traces.
For 2 A output at 36 V input and 3.3 V output, the power dissipation is approximately 3.6 W (calculated as (36-3.3)*2 A - output power). The 14-pin VQFN package has a thermal resistance around 40°C/W (estimate), so junction temperature rise is about 144°C at 25°C ambient. Ensure a copper pour of at least 1 square inch under the device to keep the junction below 150°C.
Do not exceed the 36 V input rating; use a TVS diode for load-dump protection. Ensure the enable pin is pulled up through a resistor to VIN for automatic start-up. The FB divider, if used, must use 1% tolerance resistors to maintain accuracy. Connect the BOOT pin capacitor between BOOT and SW (100 nF) as per the datasheet.
合规信息
Automotive qualified (AEC-Q100) per TI product page. RoHS/REACH status not explicitly confirmed in provided data; verify manufacturer documentation.
