MAX6628MTA+T - ±1°C Remote Digital Temp Sensor SPI/TDFN-8 | ADI
料号： MAX6628MTA+T ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $6.5 | $6.50 |
| 10 | $5.85 | $58.50 |
| 100 | $5.2 | $520.00 |
| 500 | $4.65 | $2,325.00 |
| 1,000 | $4.1 | $4,100.00 |
MAX6628MTA+T 概述
A digital temperature sensor IC is a mixed-signal device that uses an on-chip ADC to digitize a thermal-proportional signal (bandgap voltage, Vbe, or forward-diode Vf) and exposes the result over a serial bus such as SPI, I²C/SMBus, or 1-Wire. In the broader hierarchy, the MAX6628 sits in the temperature-sensor family, which is part of the sensor IC class, which itself belongs to the broader power management and analog signal chain category. Using an external diode as the sensing element decouples the hot spot from the ADC die, enabling accurate measurement of CPUs, FPGAs, ASICs, or power-stage heat sinks that the IC itself cannot physically reach.
Key features include ±1°C remote accuracy from 0°C to +125°C, ±3°C remote accuracy from -55°C to +150°C, a 12-bit (0.0625°C LSB) temperature resolution, a 2200 pF-3300 pF recommended EMI filter capacitor between DXP and DXN, and a read-only SPI interface that simplifies firmware on microcontrollers that only need temperature data. The TDFN-8 (3×3) package is thermally efficient and footprint-compatible with standard 8-pin DFN/QFN land patterns. Typical supply current is in the hundreds of microamps, and the device includes a power-on-reset circuit that forces the first conversion to begin after supply stabilization.
Architecturally, the device combines a precision current source that drives the external diode, an on-chip sigma-delta ADC that digitizes ΔVbe, a bandgap reference, calibration logic, and an SPI peripheral. The diode measurement is ratiometric and automatically compensates for series resistance and ideality factor variations when the recommended 2N3904 NPN is used.
Typical applications include CPU/FPGA thermal monitoring in servers and workstations, laptop and notebook thermal management, industrial control cabinet temperature sensing, telecom base-station equipment health monitoring, and battery-pack temperature monitoring for portable and handheld systems.
When designing with the MAX6628, place the 2N3904 (or equivalent) as physically close to the desired hot spot as possible, keep the PCB trace length to DXP/DXN short and matched, and add a 2200 pF capacitor between DXP and DXN to reject high-frequency EMI. Always add a local 0.1 µF decoupling capacitor adjacent to VDD.
This page synthesizes distributor pricing, SPI-compatible drop-in alternatives, and practical layout notes for the MAX6628MTA+T that go beyond the manufacturer datasheet to help engineers select and qualify the part quickly.
直接替换替代料： MAX6628MTA+T ——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：
MAX6628MTA
✅ 直接替换📋 参考替代料（不在目录中）
MAX6627MTA+T
✅ 直接替换📋 参考替代料（不在目录中）
MAX6628MTA+T 最大额定值与电气特性
| 传感器类型 | Digital temperature sensor with remote-diode input |
| Number of Channels | 1 remote + 1 local die |
| Remote Accuracy (0°C to +125°C) | ±1°C |
| Remote Accuracy (-55°C to +150°C) | ±3°C |
| Temperature Resolution | 12 bit (0.0625°C LSB) |
| Supply Voltage Range | +3.0 V to +5.5 V |
| 接口 | SPI-compatible, 3-wire serial, read-only |
| Remote Sensor | External diode-connected NPN (e.g., 2N3904) or substrate diode of CPU/ASIC |
| EMI Filter Capacitor (DXP–DXN) | 2200 pF typical, 3300 pF max (incl. cable capacitance) |
| 封装 | 8-pin TDFN-EP (3 mm × 3 mm) |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant |
MAX6628MTA+T 引脚配置
| 引脚 1 | GND — Ground |
| 引脚 2 | SCK — Serial clock input (SPI) |
| 引脚 3 | /CS — Chip select, active low |
| 引脚 4 | DO — Serial data output (MISO) |
| 引脚 5 | VDD — Positive supply input (+3.0 V to +5.5 V) |
| 引脚 6 | DXN — Remote-diode cathode connection |
| 引脚 7 | DXP — Remote-diode anode connection |
| 引脚 8 | EP — Exposed thermal pad (connect to GND) |
典型应用
MAX6628MTA+T 适用于 7 应用s: CPU / FPGA Thermal Monitoring in Servers, Laptop / Notebook Thermal Management, Industrial Control Cabinet Sensing, Telecom Base-Station Equipment Health Monitoring, Battery-Pack Temperature Monitoring for Portable Systems, Router / Switch Board Thermal Monitoring, LED Driver Heat-Sink Monitoring.
CPU / FPGA Thermal Monitoring in Servers
The MAX6628MTA+T monitors the substrate diode of a CPU, FPGA, or ASIC in 1U/2U servers and workstations where the 2N3904 or on-die thermal diode sits within millimeters of the hot spot. The 12-bit (0.0625°C LSB) resolution and ±1°C accuracy from 0°C to +125°C let the BMC throttle fans or trigger shutdown long before silicon limits are exceeded. The 3-wire SPI interface shares bus pins cleanly with SPI NOR flash or other slaves, saving GPIO. Because the part is read-only, firmware on the management controller is a single SPI read transaction per polling cycle, leaving headroom for telemetry logging.
推荐
Laptop / Notebook Thermal Management
Inside a laptop, the MAX6628MTA+T can monitor a remote NPN placed on the heat sink of the CPU or discrete GPU, giving the embedded controller an accurate die-temperature reading without using a chassis-mounted thermistor. The TDFN-8 (3×3) package occupies less than 9 mm² of board area and uses an exposed pad to dissipate the minimal self-heating from the analog front end. The +3.0 V to +5.5 V supply range covers both the 3.3 V system rail and any 5 V pre-regulated rail. The SPI interface allows the EC to poll temperature in a single 16-bit transaction, keeping firmware interrupt load low during heavy I/O.
推荐
Industrial Control Cabinet Sensing
In factory automation cabinets, the MAX6628MTA+T can monitor the temperature of a remote 2N3904 mounted on a heat sink, motor-drive module, or contactor, providing ±1°C feedback from 0°C to +125°C for PLCs and HMIs. The TDFN-8 package is small enough to fit inside dense I/O blocks, and the SPI interface can be daisy-chained via chip-select if multiple sensors are needed. The wide -55°C to +150°C remote range covers extreme factory-floor environments. Industrial designers benefit from the absence of calibration routines in firmware - the on-chip ADC and reference handle conversion autonomously.
推荐
Telecom Base-Station Equipment Health Monitoring
Telecom base stations require continuous thermal surveillance of PA modules, BBU boards, and outdoor enclosures. The MAX6628MTA+T connects to a remote NPN placed adjacent to the RF power amplifier or ASIC substrate diode and reports a 12-bit temperature word over SPI every conversion cycle. The device's ±3°C accuracy from -55°C to +150°C accommodates outdoor weather extremes, and the +3.0 V to +5.5 V supply integrates cleanly with -48 V → 5 V or 12 V intermediate buses. The read-only interface means baseband processors can poll temperature without risking accidental configuration writes, which is critical in carrier-grade firmware.
推荐
Battery-Pack Temperature Monitoring for Portable Systems
In handheld instruments, portable medical devices, and battery packs, the MAX6628MTA+T monitors the temperature of a remote NPN placed against a Li-ion cell stack or power-MOSFET heat spreader. The ±1°C accuracy over 0°C to +125°C is sufficient for charge-management firmware to enforce cell-temperature safety limits. The TDFN-8 (3×3) footprint is friendly to high-density BMS layouts, and the low active supply current keeps quiescent drain on the battery minimal. The SPI interface is straightforward for small Cortex-M0 class MCUs that lack I²C peripherals.
推荐
Router / Switch Board Thermal Monitoring
In enterprise switches and routers, the MAX6628MTA+T provides per-port or per-ASIC thermal telemetry by connecting to remote substrate diodes on the switch ASIC and PHY transceivers. The SPI interface can be multiplexed across multiple MAX6628 devices via individual chip-select lines, letting a single BMC read up to dozens of temperature zones. The 2200 pF EMI filter capacitor between DXP and DXN rejects the high-frequency noise typical in switching power-supply environments. The small TDFN-8 footprint allows the sensor to be placed within a few millimeters of the ASIC, minimizing trace-induced offset.
推荐
LED Driver Heat-Sink Monitoring
High-brightness LED arrays and stage-lighting fixtures use the MAX6628MTA+T to monitor a remote NPN attached to the LED heat sink, allowing the driver MCU to fold back current when the junction temperature rises. The ±1°C accuracy from 0°C to +125°C matches the thermal derating curves of most high-power LEDs. The read-only SPI interface simplifies safety firmware - the MCU cannot accidentally reconfigure the sensor. The 8-pin TDFN-EP (3×3) footprint mounts directly to the metal-core PCB ground plane, using the exposed pad for thermal grounding.
推荐
推荐产品汇总
工程参考数据： MAX6628MTA+T ——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 | MAX6628MTA | MAX6627MTA+T | MAX6628MKA-T |
|---|---|---|---|---|
| Brand | Analog Devices (Maxim Integrated) | Analog Devices | Analog Devices | Analog Devices |
| Package | TDFN-8 (3x3 mm) | TDFN-8 (3x3 mm) - same | TDFN-8 (3x3 mm) - same | SO-8 - different land pattern |
| Interface | SPI (3-wire, read-only) | SPI (3-wire, read-only) | I2C/SMBus | SPI (3-wire, read-only) |
| Remote Accuracy (0-125°C) | ±1°C | ±1°C | ±1°C | ±1°C |
| Resolution | 12 bit (0.0625°C LSB) | 12 bit (0.0625°C LSB) | 12 bit (0.0625°C LSB) | 12 bit (0.0625°C LSB) |
| Supply Voltage Range | +3.0 V to +5.5 V | +3.0 V to +5.5 V | +3.0 V to +5.5 V | +3.0 V to +5.5 V |
| Remote Sensor Type | External 2N3904 NPN | External 2N3904 NPN | External 2N3904 NPN | External 2N3904 NPN |
| Approx. Unit Price (qty 1) | ~$6.50 | ~$6.50 | ~$6.50 | ~$6.00 |
| Packaging Format | Tape & Reel | Cut tape / tube | Tape & Reel | Tape & Reel |
关键差异点
- Pin-compatible same-package alternative across SPI/I2C variants （对比 MAX6627MTA+T)
- Same die, production-ready packaging format （对比 MAX6628MTA)
- Compact TDFN-8 (3x3) saves board area vs SO-8 （对比 MAX6628MKA-T)
设计说明
Place a 2200 pF ceramic capacitor between DXP and DXN as close as possible to the IC pins to filter high-frequency EMI. The capacitor can be increased to ~3300 pF maximum including cable capacitance. Keep DXP and DXN traces short, matched in length, and routed away from switching nodes; route them over a continuous ground plane and avoid vias in the differential pair.
Connect the exposed thermal pad (EP) of the TDFN-8 package to a low-impedance ground pour with multiple vias to the inner ground plane. This both improves thermal performance and provides a stable reference for the analog front end. Place a 0.1 µF decoupling capacitor as close as possible to VDD (pin 5) with a short trace to ground.
Do not substitute the remote-sensor transistor with arbitrary small-signal NPNs without verifying ideality factor. The MAX6628MTA+T is trimmed for 2N3904 characteristics; using parts like 2N2222 may shift accuracy by 1-2°C. Do not exceed 3300 pF total capacitance between DXP and DXN - larger values will attenuate the ΔVbe signal and degrade conversion accuracy. Do not drive DXP/DXN traces near switching converter switching nodes.
合规信息
RoHS and REACH compliance per Analog Devices product page. Not AEC-Q100 qualified - this part targets commercial/industrial, not automotive. Lead-free reflow-compatible per MSL rating on datasheet packaging information.
