My Inquiry
My Account
Texas Instruments TMP422AIDCNT
- Part No.:
- TMP422AIDCNT
- Manufacturer:
- Texas Instruments
- Category:
- Analog and Digital Output
- Package:
- SOT-23-8
- Datasheet:
-
TMP422AIDCNT.pdf
- Description:
- SENSOR DIGITAL -40C-125C SOT23-8
- Quantity:
- Payment:
- Shipping:
Inventory:5,404
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
TMP422AIDCNT from Texas Instruments is a dual-channel remote/local temperature sensor IC in SOT23-8 package, featuring ±1°C remote diode accuracy (max), 12-bit resolution per channel, and SMBus™/two-wire interface. It monitors one local die temperature and two remote junctions (e.g., CPU/FPGA thermal diodes) for precision thermal management in high-density computing systems.
For engineers reviewing the TMP422AIDCNT datasheet, TMP422AIDCNT pinout, TMP422AIDCNT application, or TMP422AIDCNT equivalent, key selection criteria include remote channel count (2), SMBus address configurability via DX pins, series resistance cancellation up to 3 kΩ, and operation across –40°C to +125°C ambient range with 0.0625°C fractional resolution.
Technical Context
The TMP422AIDCNT integrates a local ADC and two independent remote ADCs with dedicated current sources (120 μA/60 μA/12 μA/6 μA selectable) for diode-connected transistors. It implements hardware-based series resistance cancellation and programmable n-factor correction (η = 1.008) to compensate for non-ideal transistor behavior.
Its SMBus interface supports write byte, read byte, send byte, and receive byte commands with timeout (25–35 ms), hysteresis (500 mV), and clock frequency up to 3.4 MHz. The device uses a pointer-register architecture to access 16+ registers including local/remote temperature, configuration, status, and N-factor correction.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Remote Accuracy | ±1°C max over –40°C to +125°C ambient, enabling direct replacement of lower-accuracy sensors without calibration. |
| Local Accuracy | ±1.5°C max over –40°C to +125°C, sufficient for on-die thermal monitoring of host ICs. |
| Resolution | 12-bit (1°C integer + 0.0625°C fractional), allowing precise thermal trending and alarm thresholding. |
| Supply Range | 2.7 V to 5.5 V - compatible with 3.3 V and 5 V system rails without level-shifting. |
| Quiescent Current | 32–38 μA at 0.0625 conversions/sec - optimized for always-on thermal monitoring in power-constrained systems. |
| Conversion Time | 100–130 ms per channel - deterministic timing for synchronized multi-sensor polling. |
| SMBus Clock Max | 3.4 MHz - supports high-speed bus arbitration in dense multi-device configurations. |
Pinout & Package
SOT23-8 package (DCN designation), 2.9 mm × 1.6 mm × 1.0 mm body, surface-mount, lead-free and RoHS compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (DX1) | Remote Channel 1 positive input | Connects to emitter/base of PNP or collector/base of NPN remote diode; also sets SMBus address bit A1. |
| 2 (DX2) | Remote Channel 1 negative input | Completes remote diode bias path for Channel 1; also sets SMBus address bit A0. |
| 3 (DX3) | Remote Channel 2 positive input | Connects to emitter/base of second PNP or collector/base of second NPN; enables dual-remote sensing. |
| 4 (DX4) | Remote Channel 2 negative input | Completes bias path for Channel 2; unused channels must be tied to GND per TI design guidance. |
| 5 (GND) | Analog/digital ground reference | Single ground pin shared by all analog and digital circuits; requires low-impedance PCB connection. |
| 6 (SDA) | SMBus data line (open-drain) | Requires external pull-up to V+; supports bidirectional communication with standard SMBus timing. |
| 7 (SCL) | SMBus clock line (open-drain) | Drives synchronous data transfer; tolerates 3.4 MHz clock with 1 μs falling-edge-to-SDA-valid timing. |
| 8 (V+) | Positive supply input | Accepts 2.7–5.5 V; includes undervoltage lockout (2.3–2.6 V) and power-on reset (1.6–2.3 V). |
Key Features
| Feature | Design Value |
|---|---|
| Two remote + one local temperature channels | Enables simultaneous monitoring of CPU core, GPU junction, and SoC die temperature in single IC footprint. |
| Hardware series resistance cancellation | Compensates up to 3 kΩPCB trace resistance automatically-eliminates need for software offset calibration. |
| Programmable n-factor correction | Adjusts ideality factor (η) to match actual transistor characteristics, improving remote accuracy across vendors. |
| Diode fault detection | Flags open-circuit, short-circuit, or reverse-biased conditions on DX pins-prevents false thermal shutdowns. |
| Multiple SMBus addresses | Four unique slave addresses (1001100b to 1001111b) set via DX1–DX4 pin states-supports up to four TMP422 devices on same bus. |
Applications
| Processor/FPGA Thermal Monitoring | Server Blade Thermal Management |
|---|---|
Use Scenario: Real-time junction temperature tracking of multi-core CPUs and FPGAs during dynamic workload scaling. IC Role / Device Role / Timing Role: Local sensor measures SoC die temperature; remote channels monitor discrete thermal diodes embedded in processor packages. Use Value: Enables adaptive clock throttling and fan control with ±1°C remote accuracy-reducing thermal margin overhead by ≥2°C vs. ±3°C alternatives. |
Use Scenario: Distributed thermal sensing across compute, memory, and I/O modules in 1U/2U rack-mounted servers. IC Role / Device Role / Timing Role: One TMP422AIDCNT per blade monitors CPU, VRM, and DIMM slot temperatures via dedicated remote diodes. Use Value: Dual remote channels reduce component count by 50% versus single-channel solutions-cutting BOM cost and PCB area. |
| LCD/DLP Projector Lamp Control | Central Office Telecom Equipment |
Use Scenario: Closed-loop thermal regulation of high-power UHP lamps and DMD cooling in professional projectors. IC Role / Device Role / Timing Role: Local sensor tracks projector chassis ambient; remote channels monitor lamp arc tube and DMD heatsink diodes. Use Value: 0.0625°C resolution enables predictive lamp life estimation and prevents thermal runaway before catastrophic failure. |
Use Scenario: Hot-spot monitoring of line cards, power supplies, and optical transceivers in carrier-grade telecom chassis. IC Role / Device Role / Timing Role: Mounted directly on line card PCBs; remote channels track ASIC junctions and DC-DC converter MOSFETs. Use Value: SMBus compatibility allows integration into existing shelf management controllers-no firmware changes required. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-channel remote/local temperature sensing applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TMP421AIDCNT | Single remote channel only; identical SMBus interface, accuracy, and package. | Insufficient for dual-remote use cases (e.g., CPU + GPU); requires two devices for same functionality. | Select when only one remote diode needs monitoring-reduces cost and layout complexity. |
| LM95235CIMMX/NOPB | 2-channel remote + 1 local, but uses SPI interface; ±1.5°C remote accuracy; no series resistance cancellation. | Requires SPI bus allocation and additional GPIOs; lacks hardware compensation for PCB trace resistance. | Choose if system already uses SPI infrastructure and can tolerate higher remote error budget. |
Compared with TMP421AIDCNT, the TMP422AIDCNT adds a second remote channel without increasing package size or supply current-enabling consolidation in space-constrained designs. Versus LM95235CIMMX/NOPB, it delivers superior remote accuracy and automatic series resistance compensation via SMBus-compatible interface.
Availability
TMP422AIDCNT is available at Aetrix Electronics and suitable for processor thermal monitoring, server blade management, and telecom equipment requiring stable component supply across extended industrial temperature ranges.
Supply support for TMP422AIDCNT 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
Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision sensing and industrial-grade IC design.
The TMP422AIDCNT belongs to TI's precision temperature sensor family, engineered specifically for high-accuracy remote junction monitoring in computing, communications, and projection systems where thermal reliability is critical.
FAQ
What is the maximum remote diode series resistance the TMP422AIDCNT can cancel?
The TMP422AIDCNT cancels up to 3 kΩof series resistance in the remote diode path-covering typical PCB trace lengths and connector resistances without requiring external calibration. This capability is implemented in hardware and active across the full operating temperature range of –40°C to +125°C. The cancellation algorithm is transparent to firmware and does not affect conversion time or SMBus latency. For optimal performance, TI recommends keeping differential capacitance below 1000 pF.
How many SMBus addresses does the TMP422AIDCNT support?
The TMP422AIDCNT supports four unique SMBus slave addresses (1001100b through 1001111b), determined by the logic states of its DX1–DX4 pins. Unlike fixed-address sensors, this pin-strapping method allows multiple TMP422AIDCNT devices to coexist on the same SMBus without address conflicts. Each address maps to a specific combination of DX1/DX2 (Channel 1) and DX3/DX4 (Channel 2) connections-no external address pins or jumpers are needed.
Does the TMP422AIDCNT require external components for basic operation?
Yes-the TMP422AIDCNT requires two external 10-kΩpull-up resistors (to V+) on SCL and SDA lines for SMBus compliance, plus a 0.1-μF ceramic bypass capacitor between V+ and GND. Remote diodes must be connected between DX1–DX2 (Channel 1) and DX3–DX4 (Channel 2); unused channels must be tied to GND. No external resistors are needed for series resistance cancellation or n-factor correction-they are handled internally.
What is the temperature resolution of the TMP422AIDCNT?
The TMP422AIDCNT provides 12-bit temperature data: the high byte delivers 1°C integer resolution, and the low byte provides 0.0625°C fractional resolution (1/16°C). Both local and remote channels share this resolution. Data is stored in two's complement format for negative values and unsigned with –64°C offset in extended mode. The resolution is fixed and not user-programmable-ensuring consistent quantization across all operating conditions.
Can the TMP422AIDCNT measure temperatures below –40°C or above +125°C?
The TMP422AIDCNT is specified for ambient operation from –40°C to +125°C, but its remote and local temperature measurement range extends to –55°C to +150°C when configured for extended binary mode (RANGE bit = 1 in Configuration Register 1). In this mode, an offset of 64 is added, enabling readings from –64°C to +191°C-though practical limits are constrained by diode performance and absolute maximum ratings. Values outside –64°C to +191°C saturate at C0h (–64°C) or FFh (+191°C).
TMP422AIDCNT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- SOT-23-8
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Sensor Type:
- Digital, Local/Remote
- Sensing Temperature - Local:
- -40°C ~ 125°C
- Sensing Temperature - Remote:
- -64°C ~ 191°C
- Output Type:
- SMBus
- Voltage - Supply:
- 2.7V ~ 5.5V
- Resolution:
- 11 b
- Features:
- One-Shot, Output Switch, Programmable Limit, Shutdown Mode
- Accuracy - Highest (Lowest):
- ±1.5°C (±2.5°C)
- Test Condition:
- 15°C ~ 85°C (-40°C ~ 125°C)
- Operating Temperature:
- -40°C ~ 125°C
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
- Supplier Device Package:
- SOT-23-8
TMP422AIDCNT FAQ
1.How can I place an order for TMP422AIDCNT through Aetrix?
Please submit a Request for Quotation (RFQ) for TMP422AIDCNT 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 TMP422AIDCNT reliable?
The price and inventory of TMP422AIDCNT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TMP422AIDCNT is usually 5 days.
3.What payment methods are accepted for TMP422AIDCNT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TMP422AIDCNT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TMP422AIDCNT?
TMP422AIDCNT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TMP422AIDCNT 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 TMP422AIDCNT?
For technical support, including TMP422AIDCNT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TMP422AIDCNT requirements.
6.How does Aetrix verify that TMP422AIDCNT is sourced from the original manufacturer or authorized distributors?
All TMP422AIDCNT 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 TMP422AIDCNT meets industry standards.
7.What is the process for return or replacement of TMP422AIDCNT?
All TMP422AIDCNT units undergo pre-shipment inspection (PSI). If there is an issue with TMP422AIDCNT, 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 TMP422AIDCNT part is unused and in its original packaging.
Return procedure for TMP422AIDCNT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TMP422AIDCNT Tags
-
MCP9700T-E/TT
Microchip Technology
-
MCP9700T-E/LT
Microchip Technology
-
MCP9701T-E/TT
Microchip Technology
-
MCP9701T-E/LT
Microchip Technology
-
TMP235A4DBZR
Texas Instruments
-
MCP9700AT-E/TT
Microchip Technology
-
MCP9700AT-E/LT
Microchip Technology
-
MCP9701AT-E/LT
Microchip Technology
-
MCP9701AT-E/TT
Microchip Technology
,TO-226_straightlead.jpg)
-
LM335Z
STMicroelectronics
-
TMP1075NDRLR
Texas Instruments
-
TMP1075DGKR
Texas Instruments
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…
