LM63CIMAX - ±1°C Remote Diode Temp Sensor + Fan Control | TI
料号： LM63CIMAX ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $3.07 | $30.70 |
| 100 | $2.74 | $274.00 |
| 500 | $2.45 | $1,225.00 |
| 1,000 | $2.18 | $2,180.00 |
LM63CIMAX 概述
A remote-diode temperature sensor is a class of thermal management IC that exploits the temperature-dependent base-emitter voltage of a bipolar or substrate diode to infer junction temperature far away from the sensor itself. Remote-diode sensors sit within the thermal management IC hierarchy (PMIC > thermal management > temperature sensor > remote-diode sensor) and are essential in desktop PCs, servers, and any system where a hot spot must be monitored without placing the sensor physically on the heat source.
Key specifications include ±1°C remote-diode accuracy (0°C to +125°C) and ±3°C accuracy from 0°C to +85°C, 8-/10-bit-plus-sign internal/remote resolution, a 2-wire SMBus (I²C-compatible) digital interface, and a programmable PWM fan-control output with tachometer input for closed-loop RPM feedback. Supply voltage is 3.0V to 3.6V and quiescent current is roughly 1.3 mA during active conversion.
The LM63CIMAX integrates a sigma-delta ADC for noise rejection, on-chip offset trim performed at the factory to minimize diode non-ideality errors, and a tachometer counter that reports fan RPM over the SMBus. The MAX package exposes a single remote-diode differential input pair (D+/D−) and the fan-driver PWM output (Fan Out), plus the digital interface pins (SDA, SCL, ALERT, GND, VDD, FAN_IN/TACH).
Typical applications include CPU/GPU thermal monitoring in desktop and server motherboards, fan-speed control in telecom equipment, and chassis-intake temperature sensing in industrial controllers. The integrated fan tachometer input enables closed-loop RPM regulation rather than open-loop PWM drive, which reduces acoustic noise and extends fan life.
When designing with the LM63CIMAX, keep the D+/D− routing balanced, length-matched, and surrounded by ground to cancel noise pickup that would otherwise appear as temperature noise. Decouple VDD close to the IC with a 0.1 µF ceramic capacitor and avoid routing the remote-diode traces near switching fan-drive signals to preserve accuracy.
直接替换替代料： LM63CIMAX ——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： LM63CIMAX （相同外形与封装尺寸） ——差异在于 Package, Function, Remote Diode Accuracy, Fan Control Output, Interface.
快速对比工具——选择替代料号进行并排对比：
LM63CIMAX/NOPB
✅ 直接替换✓ 有现货
联系询价
查看数据手册 →LM63CIMA/NOPB
✅ 直接替换✓ 有现货
$2.05 / 个
查看数据手册 →LM63CIMAX/NOPB
✅ 直接替换✓ 有现货
联系询价
查看数据手册 →LM63CIMAX 最大额定值与电气特性
| 功能 | Remote Diode Temperature Sensor with PWM Fan Driver |
| Remote Diode Accuracy | ±1°C (0°C to +125°C) |
| Local Sensor Accuracy | ±3°C (0°C to +85°C) |
| Supply Voltage (VDD) | 3.0 V to 3.6 V |
| Supply Current (active) | 1.3 mA typ |
| Resolution (Remote) | 10-bit + sign |
| Resolution (Local) | 8-bit + sign |
| 接口 | 2-Wire SMBus (I²C-compatible) |
| Fan Output | PWM, open-drain |
| Tachometer Input | Yes (Fan RPM feedback) |
| Remote Diode Inputs | D+ / D− differential pair |
| 工作温度 | 0°C to +125°C |
| 封装 | 8-pin SOIC (MAX) |
| 安装类型 | Surface Mount |
| MSL 等级 | 1 |
| RoHS 状态 | Compliant |
LM63CIMAX 引脚配置
| 引脚 1 | GND — Ground reference for IC and remote-diode measurement |
| 引脚 2 | VDD — Positive supply input, 3.0V to 3.6V (3.3V typical) |
| 引脚 3 | D+ — Remote-diode positive input (anode of substrate diode) |
| 引脚 4 | D− — Remote-diode negative input (cathode of substrate diode) |
| 引脚 5 | ALERT — Open-drain interrupt output (active low when threshold exceeded) |
| 引脚 6 | TACH / FAN_IN — Fan tachometer input for closed-loop RPM feedback |
| 引脚 7 | Fan Out — PWM fan-driver output (open-drain) |
| 引脚 8 | SDA — SMBus/I²C data line (open-drain, requires external pull-up) |
典型应用
LM63CIMAX 适用于 6 应用s: CPU/GPU Thermal Monitoring on Desktop & Server Boards, Closed-Loop Fan-Speed Control in Telecom & Networking Equipment, Chassis-Intake Air Temperature Sensing in Industrial Controllers, Laptop & Notebook Thermal Management, Set-Top Box / Game Console Fan Control, FPGA / ASIC Board Thermal Protection.
CPU/GPU Thermal Monitoring on Desktop & Server Boards
The LM63CIMAX fits CPU/GPU thermal monitoring because its remote-diode input accurately reads the substrate diode of a processor or graphics chip from a distance, while its local channel monitors board-level air temperature. With ±1% accuracy over 0°C to +125°C on the remote channel and a 2-wire SMBus interface, it delivers CPU die temperature readings directly to the EC/super-IO at typical sample rates of 1 Hz. Place the LM63CIMAX within 10 cm of the remote diode, route D+/D− as a length-matched differential pair surrounded by ground, and use the integrated PWM output to drive the heatsink fan's 4-wire PWM input.
推荐
Closed-Loop Fan-Speed Control in Telecom & Networking Equipment
The LM63CIMAX is well-suited to closed-loop fan-speed control in telecom and networking equipment because it combines a remote-diode temperature sensor, a PWM fan-driver output, and a tachometer input on the same die. The firmware can program a target RPM and the LM63CIMAX's tachometer counter reports the actual fan speed over SMBus, enabling acoustic-aware variable-speed cooling. The 8-SOIC package and 3.3V single-rail supply fit typical line-card / base-station board constraints, and the open-drain PWM output can sink up to the fan driver's gate capacitance directly.
推荐
Chassis-Intake Air Temperature Sensing in Industrial Controllers
For chassis-intake air temperature sensing in industrial controllers, the LM63CIMAX uses its local on-die sensor to monitor ambient inlet air with ±3°C accuracy from 0°C to +85°C. This reading can be combined with the remote-diode reading to model thermal gradients across the chassis and trigger fan-boost profiles before ASIC hotspots cross the alarm threshold. The 8-SOIC (MAX) package and SMBus interface integrate cleanly into any 3.3V-managed industrial backplane.
推荐
Laptop & Notebook Thermal Management
The LM63CIMAX supports laptop and notebook thermal management by reading the CPU's remote substrate diode and driving the system fan's PWM input with a speed command derived from that temperature. The 1.3 mA active current is low enough to leave the IC in always-on mode for instant system wake on thermal alarm, and the SMBus interface lets the embedded controller share the temperature with the OS for graceful throttling. Pair it with a 4-wire PWM fan to enable silent idle / active-load acoustic profiles.
推荐
Set-Top Box / Game Console Fan Control
In set-top boxes and game consoles, the LM63CIMAX provides single-IC remote-diode temperature sensing plus PWM fan control in an 8-SOIC package that fits a small main board. The integrated ALERT pin can wake the SoC when SoC temperature exceeds a programmable threshold, and the tachometer input lets firmware verify the fan is actually spinning at the commanded RPM. The 3.0V-to-3.6V supply aligns with 3.3V system rails common in consumer electronics.
推荐
FPGA / ASIC Board Thermal Protection
The LM63CIMAX is a strong choice for FPGA/ASIC board thermal protection because its remote-diode input can directly monitor the substrate diode of large FPGAs and ASICs whose package exposes a thermal diode. With ±1% accuracy over 0°C to +125°C and an ALERT interrupt output, the LM63CIMAX can notify the host MCU immediately when an FPGA junction approaches its 100°C limit. The integrated PWM fan driver then throttles the heatsink fan to hold junction temperature below the limit without external fan-driver ICs.
推荐
推荐产品汇总
工程参考数据： LM63CIMAX ——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 | LM63CIMAX/NOPB | LM63CIMA/NOPB | LM63CIMA |
|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 8-SOIC (MAX) | 8-SOIC (MAX) - same | 8-SOIC (MA) - smaller | 8-SOIC (MA) - smaller |
| Remote-Diode Accuracy | ±1°C (0°C to +125°C) | ±1°C (0°C to +125°C) | ±1°C (0°C to +125°C) | ±1°C (0°C to +125°C) |
| Local-Sensor Accuracy | ±3°C (0°C to +85°C) | ±3°C (0°C to +85°C) | ±3°C (0°C to +85°C) | ±3°C (0°C to +85°C) |
| Interface | 2-Wire SMBus | 2-Wire SMBus | 2-Wire SMBus | 2-Wire SMBus |
| Supply Voltage | 3.0 V to 3.6 V | 3.0 V to 3.6 V | 3.0 V to 3.6 V | 3.0 V to 3.6 V |
| Resolution (bits) | 10-bit + sign (remote), 8-bit + sign (local) | 10-bit + sign (remote), 8-bit + sign (local) | 10-bit + sign (remote), 8-bit + sign (local) | 10-bit + sign (remote), 8-bit + sign (local) |
| RoHS / Lead-Free | Compliant / Yes | Compliant / Yes (explicit) | Compliant / Yes (explicit) | Check datasheet |
| Tachometer Input | Yes | Yes | Yes | Yes |
| PWM Fan Output | Yes (open-drain) | Yes (open-drain) | Yes (open-drain) | Yes (open-drain) |
关键差异点
- True 8-SOIC MAX package with full 8-pin layout （对比 LM63CIMA (MA package))
- Drop-in compatibility with /NOPB lead-free variant （对比 Discrete LM35 analog + firmware fan-control routine)
- Integrated tachometer feedback for closed-loop RPM control （对比 MAX31760 (multi-fan, non-pin-compatible))
设计说明
Estimated: route the D+ and D− traces as a length-matched differential pair (≤10 cm) over a continuous ground pour, and avoid running them parallel to or under the fan-driver PWM output. The remote-diode measurement is a low-level current/voltage conversion (typically 100 µA bias) that is highly susceptible to leakage from switching fan drive signals. Place the LM63 within 3 cm of the remote diode to preserve ±1°C performance.
Place a 0.1 µF ceramic decoupling capacitor as physically close as possible to the VDD pin (Pin 2), with a 10 µF bulk capacitor on the same 3.3 V rail. The SMBus lines (SDA on Pin 8, SCL on Pin 4, ALERT on Pin 5) are open-drain and require external pull-up resistors (typically 2.2 kΩ to 10 kΩ depending on bus capacitance) to 3.3 V. The PWM Fan Out (Pin 7) and TACH/FAN_IN (Pin 6) pins should be guarded against ESD with TVS diodes if the fan is on a connector.
Do not float the ADD pin (Pin 4 / SCL pad or dedicated ADD) on the LM63 — the ADD pin sets the SMBus slave address (0x4C or 0x4D) and floating it can latch an indeterminate address. Also do not assume the /NOPB suffix is optional: if your assembly line is Pb-free, the standard LM63CIMAX part number (non-/NOPB) may have SnPb terminal finish that fails the RoHS compliance step. Use LM63CIMAX/NOPB explicitly for RoHS-compliant assemblies.
Estimated: at typical fan-duty operation (50% PWM at 25 kHz, 3.3 V), the LM63CIMAX self-heating from the open-drain fan-output switching edge is well under 0.2°C. However, mounting the IC adjacent to the fan-connector step-down regulator or PWM power-stage heatsink can introduce local self-heating bias on the local on-die sensor. Mount the LM63 on the cooler side of the board, away from the fan-driver power components, to avoid adding to the ±3°C local-sensor accuracy budget.
合规信息
LM63CIMAX is RoHS compliant per TI product page; the /NOPB variant explicitly carries lead-free terminal finish. The LM63CIMAX is not AEC-Q100 qualified — for automotive thermal management, choose an AEC-Q100 qualified temperature sensor instead.
