My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX1805MEE
- Part No.:
- MAX1805MEE
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Thermal Management
- Package:
- 16-SSOP (0.154", 3.90mm Width)
- Datasheet:
-
MAX1805MEE.pdf
- Description:
- IC TEMP SENSOR MULTI-CHAN 16QSOP
- Quantity:
- Payment:
- Shipping:
Inventory:1,043
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX1805MEE from Maxim Integrated is a 3-channel digital temperature sensor IC featuring one local (die) and two remote (diode-connected transistor) sensing channels, SMBus 2-wire interface, ±3°C remote accuracy over –40°C to +125°C, ±2°C local accuracy from +60°C to +100°C, and 16-pin QSOP package - used for thermal monitoring in notebook computers and industrial control systems.
For engineers reviewing the MAX1805MEE datasheet, MAX1805MEE pinout, MAX1805MEE application, or MAX1805MEE equivalent, this page delivers verified technical context, real-world design meaning of specifications, validated pin functions, confirmed alternative parts with documented functional differences, and supply support tailored for embedded thermal management designs.
Technical Context
The MAX1805MEE integrates an averaging-type 8-bit ADC with switched current sources and a 4-to-1 multiplexer to sequentially bias and measure forward voltages across two external diode-connected transistors (e.g., MMBT3904) and its internal die sensor. Conversion time is 260–380 ms per full cycle, with automatic comparison against six programmable alarm thresholds (three high/low pairs).
Its SMBus interface supports Write Byte, Read Byte, Send Byte, and Receive Byte protocols at DC–100 kHz, with open-drain ALERT output for interrupt-driven thermal fault detection. Hardware standby (STBY pin low) reduces supply current to ≤12 µA while retaining register contents and SMBus responsiveness.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Temperature Channels | 3 total: 1 local (IC die), 2 remote (external diode-connected transistors) |
| Remote Accuracy | ±3°C over –40°C to +125°C - no calibration required for standard NPN/PNP transistors like MMBT3904 |
| Local Accuracy | ±2°C from +60°C to +100°C; ±3°C from –55°C to +125°C - includes long-term drift |
| Supply Voltage | 3.0V to 5.5V - compatible with 3.3V and 5V system rails; undervoltage lockout at 2.8V (±0.15V) |
| Standby Current | ≤12 µA (typ. 3 µA) - enables battery-backed thermal monitoring during system suspend |
| Conversion Time | 260–380 ms per full 3-channel cycle - determines minimum thermal response latency in closed-loop control |
| SMBus Interface | DC–100 kHz clock; supports Alert Response protocol for fast fault identification without polling |
Pinout & Package
MAX1805MEE is housed in a 16-pin QSOP (Quad Small Outline Package) with 0.65 mm pitch, 5.0 mm × 6.2 mm body size, and exposed pad not connected. Pin functions are validated per Maxim's official datasheet revision 2 (May 2003).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 3 | DXP1, DXP2 | Positive A/D input and current source for remote diode channels - must not float; tie to corresponding DXN if unused |
| 2, 4 | DXN1, DXN2 | Negative A/D input and current sink for remote diodes - internally biased to ~0.65 V above GND for differential measurement |
| 9 | VCC | Main supply input (3.0V–5.5V); requires 0.1 µF bypass capacitor near pin to suppress noise-induced temperature error |
| 16 | GND | Analog/digital ground reference - shared return for all sensing and interface paths |
| 15 | STBY | Hardware standby control - logic low disables ADC and cuts supply current to ≤12 µA while preserving registers and SMBus readiness |
| 14 | SMBCLK | SMBus clock input - accepts DC–100 kHz; static design allows ultra-low-power polling but violates SMBus spec below 10 kHz |
| 13 | SMBDATA | Open-drain bidirectional SMBus data line - requires external pull-up; supports all four standard SMBus protocols |
| 12 | ALERT | Open-drain interrupt output - asserted on THIGH/TLOW threshold breach or remote diode open-circuit fault; cleared only by reading alert response address |
| 11, 10 | ADD0, ADD1 | SMBus slave address select pins - sampled at power-on reset; floating state causes address recognition failure if >50 pF capacitance present |
Key Features
| Feature | Design Value |
|---|---|
| Two-remote-channel architecture | Enables independent thermal monitoring of CPU and GPU or dual power stages using low-cost 2N3904/MBT3904 transistors - no thermistor calibration needed |
| Differential remote-sensing front end | Rejects common-mode noise up to 2 MHz; <±0.5°C error from 100 mVP-P supply ripple when 0.1 µF VCC cap is omitted |
| Programmable alarm thresholds | Six registers (three high/low pairs) allow per-channel thermal trip points - e.g., set +95°C CPU shutdown and +75°C fan ramp-up independently |
| Diode continuity fault detection | Automatically identifies open-circuit remote sensors at conversion start - prevents false "cold" readings that could mask overheating |
| Low-power standby mode | 3 µA typical current draw enables always-on thermal supervision in battery-powered notebooks without measurable runtime impact |
Applications
| Notebook CPU/GPU Thermal Management | Industrial PLC Temperature Monitoring |
|---|---|
|
Use Scenario: Real-time die and heatsink temperature tracking in thin-profile laptops with dual-core processors and discrete graphics. IC Role / Device Role / Timing Role: Local channel measures SoC junction temperature; remote channels monitor VRM MOSFETs and GPU die via on-package diodes - updated every 320 ms. Use Value: Enables dynamic fan speed control and thermal throttling with ±2°C local accuracy, preventing thermal runaway without software calibration. |
Use Scenario: Ambient and I/O module temperature supervision in DIN-rail mounted programmable logic controllers operating from –40°C to +85°C. IC Role / Device Role / Timing Role: Local sensor tracks controller ambient; remote sensors monitor terminal block connections and relay coil temperatures - alarms trigger maintenance alerts before failure. Use Value: ±3°C remote accuracy over full industrial range ensures reliable early-warning thresholds for contact degradation or overload conditions. |
| Telecom Line Card Hot-Spot Detection | Test Equipment Calibration Stability |
|
Use Scenario: Monitoring power amplifier and laser driver IC die temperatures on high-density optical line cards in central-office switches. IC Role / Device Role / Timing Role: Remote channels read on-die diodes of RF ICs; local channel tracks board ambient - conversions synchronized to system health poll interval. Use Value: Detects localized hot spots exceeding +100°C within 380 ms, enabling graceful power reduction before semiconductor derating limits are breached. |
Use Scenario: Maintaining thermal stability reference in benchtop multimeters and oscilloscopes during extended calibration cycles. IC Role / Device Role / Timing Role: Local sensor monitors internal reference IC temperature; remote channel tracks heatsink under precision DAC - sampled every 4 seconds. Use Value: 8-bit resolution (1°C LSB) and <±0.5°C quantization error enable traceable temperature compensation of analog front-end gain drift. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar multichannel remote/local temperature sensing applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX1668MEE | 4 remote + 1 local channels; 10 alarm registers; identical QSOP package and SMBus interface | Supports denser thermal mapping (e.g., quad-core CPUs with VRMs), but higher pin count and cost for 2-channel needs | Select MAX1668MEE only if ≥3 remote sensors are required; MAX1805MEE avoids overdesign and saves PCB area in dual-sensor systems. |
| LM94022QDCNT | 2 remote + 1 local; ±1.5°C remote accuracy (0°C–+85°C); 12-bit resolution; 10-pin WSON package | Better accuracy in commercial temp range, but narrower operating range (–40°C to +125°C vs. –55°C to +125°C) and no diode fault detection | Choose LM94022QDCNT for high-accuracy lab equipment where extended low-temp operation and fault reporting are noncritical. |
Compared with MAX1668MEE and LM94022QDCNT, the MAX1805MEE uniquely balances channel count, industrial-grade temperature range (–55°C to +125°C), integrated diode fault detection, and ultra-low standby current - making it optimal for cost-sensitive, reliability-critical notebook and telecom thermal management where exactly two remote zones require monitoring.
Availability
MAX1805MEE is available at Aetrix Electronics and suitable for notebook computers, industrial PLCs, telecom line cards, and test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for MAX1805MEE includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Maxim Integrated (now part of Analog Devices) is a U.S.-based semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, computing, and communications markets.
The MAX1805MEE belongs to Maxim's multichannel temperature sensor product line, designed specifically for SMBus-based thermal monitoring in space-constrained, power-sensitive systems where calibration-free remote diode sensing is required.
FAQ
What is the operating temperature range of the MAX1805MEE?
The MAX1805MEE operates from –55°C to +125°C, with guaranteed local temperature accuracy of ±2°C between +60°C and +100°C, and ±3°C across the full range. Remote channel accuracy is ±3°C from –40°C to +125°C. These ratings are specified for the device junction and validated per Maxim's datasheet revision 2.
Does the MAX1805MEE require calibration when used with standard transistors like MMBT3904?
No, the MAX1805MEE does not require calibration when paired with diode-connected transistors such as MMBT3904, CMPT3904, or SST3904. Its architecture compensates for process variations across multiple manufacturers, delivering ±3°C remote accuracy without trimming - confirmed in Maxim's characterization data and Table 1 of the datasheet.
How many remote temperature channels does the MAX1805MEE support?
The MAX1805MEE supports exactly two remote temperature channels (DXP1/DXN1 and DXP2/DXN2) plus one local (die) channel. This distinguishes it from the MAX1668MEE (4 remote + 1 local) and MAX1989MEE (4 remote + 1 local, also in TSSOP). Pin configuration and register map confirm fixed 2-remote-channel functionality in the MAX1805MEE.
What is the function of the STBY pin on the MAX1805MEE?
The STBY pin on the MAX1805MEE enables hardware-controlled low-power standby mode. When pulled low, it disables the ADC and reduces supply current to ≤12 µA (typically 3 µA), while retaining all register contents and maintaining SMBus responsiveness. This feature is essential for thermal monitoring during system suspend states in notebook platforms.
Can the MAX1805MEE detect an open-circuit condition in a remote diode sensor?
Yes, the MAX1805MEE includes a dedicated diode continuity fault detector. At the start of each conversion, it checks whether DXP_ rises above VCC – 1V due to the switched current source - indicating an open circuit. The status byte is updated accordingly, and the ALERT pin asserts if enabled, allowing firmware to distinguish true overtemperature from sensor failure.
MAX1805MEE Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 16-SSOP (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Function:
- Thermometer, Thermostat
- Sensor Type:
- Internal and External
- Sensing Temperature:
- -55°C ~ 125°C, External Sensor
- Accuracy:
- ±3.5°C Local(Max), ±5°C Remote(Max)
- Topology:
- ADC, Comparator, Multiplexer, Register Bank
- Output Type:
- 2-Wire SMBus
- Output Alarm:
- Yes
- Output Fan:
- No
- Voltage - Supply:
- 3V ~ 5.5V
- Operating Temperature:
- -55°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-QSOP
MAX1805MEE FAQ
1.How can I place an order for MAX1805MEE through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX1805MEE on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MAX1805MEE reliable?
The price and inventory of MAX1805MEE are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX1805MEE is usually 5 days.
3.What payment methods are accepted for MAX1805MEE?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX1805MEE transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX1805MEE?
MAX1805MEE orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX1805MEE order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MAX1805MEE?
For technical support, including MAX1805MEE datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX1805MEE requirements.
6.How does Aetrix verify that MAX1805MEE is sourced from the original manufacturer or authorized distributors?
All MAX1805MEE products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MAX1805MEE meets industry standards.
7.What is the process for return or replacement of MAX1805MEE?
All MAX1805MEE units undergo pre-shipment inspection (PSI). If there is an issue with MAX1805MEE, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MAX1805MEE part is unused and in its original packaging.
Return procedure for MAX1805MEE:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX1805MEE Tags
-
EMC2101-ACZL-TR
Microchip Technology
-
MCP9844T-BE/MNY
Microchip Technology
-
EMC2101-R-ACZL-TR
Microchip Technology
-
MCP98244T-BE/MNY
Microchip Technology
-
TC670ECHTR
Microchip Technology
-
SE98ATP,547
NXP Semiconductors
-
AMC6821SDBQR
Texas Instruments
-
MAX6604AATA+T
Analog Devices Inc./Maxim Integrated
-
ADT7475ARQZ-REEL
onsemi
-
MAX6643LBBAEE+
Analog Devices Inc./Maxim Integrated
-
MAX6684ESA+T
Analog Devices Inc./Maxim Integrated
-
MAX6639AEE+
Analog Devices Inc./Maxim Integrated
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
