LM5085QMYE/ - 75V PFET Buck Controller | Texas Instruments
料号： LM5085QMYE/ ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $2.7137 | $2.71 |
| 10 | $2.7137 | $27.14 |
| 100 | $2.7137 | $271.37 |
| 500 | $2.7137 | $1,356.85 |
| 1,000 | $2.7137 | $2,713.70 |
LM5085QMYE/ 概述
A buck switching controller is a type of DC-DC converter controller that drives an external switching element to reduce a higher input voltage to a regulated lower voltage. The LM5085 belongs to the power-management hierarchy: buck regulator controller, DC-DC switching controller, and power-management IC. Its PFET gate driver and constant-on-time control principle enable high-voltage operation without the complexity of an actively driven high-side N-channel MOSFET.
Key features include a wide 4.5 V to 75 V operating input range, 100% maximum duty-cycle capability, adjustable current limiting using either the PFET RDS(ON) or a current-sense resistor, and cycle-by-cycle current limiting. The controller includes a built-in high-voltage bias regulator and PFET gate driver. According to the Texas Instruments LM5085 product information, the device offers nearly constant operating frequency with line and load variation.
The constant-on-time architecture avoids loop compensation and is intended to provide an ultrafast transient response. Switching frequency can be programmed up to 1 MHz, allowing designers to select between smaller magnetics, higher switching rates, or lower switching losses. The PFET drive arrangement supports simplified gate-drive requirements and extends regulation range through 100% duty-cycle operation at low input voltage.
Typical applications include industrial 24 V or 48 V bus step-down supplies, automotive electrical-control units, telecom and networking equipment, test and measurement instruments, and high-voltage battery-derived power rails. The controller operates with external power components, so final output current, efficiency, ripple, and thermal performance depend on the selected PFET, inductor, capacitors, and PCB layout.
For robust implementation, place the controller and high-current switching loop tightly, maintain a compact high-dv/dt gate-drive path, use adequate input and output capacitance, and verify current-limit behavior across VIN, load, and temperature. This page combines manufacturer information, distributor availability, application guidance, and design-focused considerations for engineers evaluating the LM5085-Q1 family.
直接替换替代料： LM5085QMYE/ ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
LM5085MYE/NOPB
✅ 直接替换📋 参考替代料（不在目录中）
LM5085QMYE
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LM5085MM
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LM5085MME
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LM5085MMX
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LM5085QMYE/ 最大额定值与电气特性
| Product Type | PFET buck switching controller |
| 输入电压范围 | 4.5 V to 75 V |
| 输出类型 | Positive step-down |
| Control Topology | Constant on-time (COT) |
| 输出数量 | 1 |
| Maximum Duty Cycle | 100% |
| 开关频率 | Programmable up to 1 MHz |
| Gate Driver | PFET gate driver |
| Current Limiting | Adjustable using PFET RDS(ON) or current-sense resistor |
| Current-Limiting Mode | Cycle-by-cycle current limiting |
| Bias Supply | Built-in high-voltage bias regulator |
| Transient Response | Ultrafast; no loop compensation required |
| Operating Frequency Behavior | Nearly constant with line and load variation |
| Automotive Qualification | AEC-Q100 Grade 1 qualified for LM5085-Q1 |
| Automotive Junction Temperature | -40°C to 125°C |
| 封装 | 8-HVSSOP exposed pad |
| Surface Mount | Yes |
| RoHS 状态 | Not stated in provided data |
| REACH Status | Not stated in provided data |
LM5085QMYE/ 8-hvssop exposed pad 引脚配置指南
LM5085QMYE/（8-hvssop exposed pad 封装）的引脚配置。 该功率器件具有栅极、漏极和源极端子。对于无极性封装，请参阅制造商数据手册以了解确切的引脚 1 方向和封装尺寸细节。常见应用包括电源设计、电机驱动和负载开关。
暂无详细引脚数据： LM5085QMYE/.
请参阅 数据手册 以查看完整引脚配置。
典型应用
LM5085QMYE/ 适用于 6 应用s: Industrial 24 V Bus Step-Down Supply, Automotive Electrical-Control Unit, 48 V Telecom and Networking Power Rail, High-Voltage Battery-Derived Auxiliary Rail, Test and Measurement Instrument Supply, Industrial Sensor and Gateway Node.
Industrial 24 V Bus Step-Down Supply
LM5085QMYE/ fits 24 V industrial input buses because its 4.5 V to 75 V operating range covers nominal 24 V systems while retaining margin for industrial transients. The constant-on-time PFET control supports high-efficiency conversion with external magnetics. Designers can select the switching frequency up to 1 MHz to balance inductor size, ripple, switching loss, and EMI control. The exposed-pad package helps transfer heat from the controller, while the high-voltage bias regulator supplies the internal gate-drive circuitry.
推荐
Automotive Electrical-Control Unit
LM5085QMYE/ is appropriate when the production design requires the LM5085-Q1 automotive qualification path. Texas Instruments identifies the Q1 family as AEC-Q100 Grade 1 qualified for -40°C to 125°C junction operation. Its 4.5 V to 75 V input range can support vehicle power systems after upstream protection, filtering, and transient control are added. Cycle-by-cycle current limiting and programmable frequency help protect the external power stage during load steps, faults, and startup.
推荐
48 V Telecom and Networking Power Rail
The LM5085QMYE/ input range is well suited to 48 V telecom and networking infrastructure where a local buck stage must produce a lower voltage rail for processors, communications ICs, or storage. Constant-on-time operation provides fast transient response without loop-compensation components, while programmable frequency allows optimization for the chosen inductor and output-capacitor network. The external PFET architecture provides flexibility for current and thermal requirements that cannot be met by a fully integrated regulator.
推荐
High-Voltage Battery-Derived Auxiliary Rail
LM5085QMYE/ can be used in battery-derived systems where the available input may vary across a broad range and a regulated auxiliary rail is required. The 4.5 V minimum operating voltage supports lower input conditions, while the 75 V maximum supports higher transient headroom when upstream clamping is specified. Its 100% duty-cycle capability helps extend regulation at low input voltage. Designers must still validate battery chemistry, maximum transient, reverse polarity, and load-dump protection separately.
推荐
Test and Measurement Instrument Supply
LM5085QMYE/ is useful for high-voltage front-end supplies in test and measurement equipment where the controller must operate above conventional low-voltage regulator ranges. The adjustable switching frequency permits optimization for a compact instrument enclosure, and the no-loop-compensation architecture can simplify control design. External filtering, current limiting, and precise feedback components should be selected to meet the instrument’s noise and regulation requirements. The 8-HVSSOP package also supports compact PCB placement beside the power stage.
推荐
Industrial Sensor and Gateway Node
LM5085QMYE/ can generate a lower local rail for industrial sensor gateways or remote monitoring nodes that receive power from a 24 V or 48 V bus. The controller’s high-voltage tolerance reduces the need for a separate pre-regulator, while constant-on-time control can improve response to changing sensor and radio loads. A practical design should include input surge protection, output bulk capacitance, and careful separation between the switching node and sensitive measurement circuits to maintain signal integrity.
推荐
推荐产品汇总
工程参考数据： LM5085QMYE/ ——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 | LM5085MYE/NOPB | LM5085QMYE | LM5085MM | LM5085MME | LM5085MMX |
|---|---|---|---|---|---|---|
| Package | 8-HVSSOP exposed pad | 8-HVSSOP exposed pad | 8-HVSSOP exposed pad | 8-HVSSOP family; verify exact variant | 8-HVSSOP family; verify exact variant | 8-HVSSOP family; verify exact variant |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
关键差异点
- Wide high-voltage operating range （对比 LM5085MYE/NOPB)
- Automotive-grade family qualification （对比 LM5085MYE/NOPB)
- Constant-on-time control without loop compensation （对比 LM5085MM)
设计说明
Size the external PFET, inductor, and current-sense network for the maximum input voltage, output current, duty cycle, and thermal condition rather than nominal conditions alone. Constant-on-time control can support 100% duty-cycle operation at low input voltage, so verify dropout behavior at the lowest expected input and the highest load. Confirm the selected current-limit method against RDS(ON) tolerance and fault-current requirements.
Keep the PFET, switching node, inductor, and high-current input/output capacitor loop compact to reduce parasitic inductance and switching-node ringing. Route the gate-drive and feedback paths away from the power loop, use a quiet ground reference for feedback, and place the controller close to the bias and compensation components specified by Texas Instruments. Proper exposed-pad soldering and copper heat spreading are important for reliable thermal performance.
Do not assume that the controller datasheet’s 4.5 V to 75 V operating range removes the need for input surge, reverse-polarity, or fault protection. Check the exact package pinout and exposed-pad connection in the official datasheet, verify the production ordering suffix, and validate current limiting across temperature and PFET tolerance. Distributor snippets confirm the family and package but do not replace design-level electrical review.
合规信息
Texas Instruments identifies the LM5085-Q1 family as AEC-Q100 Grade 1 qualified with -40°C to 125°C operating junction temperature. RoHS, REACH, lead-free, halogen-free, and conflict-minerals status are not stated in the provided data.
