TMP121 Digital Temperature Sensor

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TMP121 Digital Temperature Sensor

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Part Number
TMP121
Manufacturer
Texas Instruments
Package
SOT23-6, package designator DBV
Category
Sensor
Product Type
Digital temperature sensor

Quick Sourcing Note

TMP121 from Texas Instruments is a digital temperature sensor in a SOT23-6, DBV package. It provides an SPI-compatible digital output with 12-bit plus sign temperature resolution and 0.0625 °C steps. The device operates from a 2.7 to 5.5 V supply and is specified across -40 to +125 °C, with an operating temperature range of -55 to +150 °C. Key parameters include typical ±0.5 °C accuracy from -25 °C to +85 °C, 35 µA typical quiescent current, and 0.1 µA typical shutdown current. It supports compact board-level temperature measurement using SCK, CS, and SO pins.

Specifications

TypeDescription
Part NumberTMP121
ManufacturerTexas Instruments
Product TypeDigital temperature sensor
CategorySensor
Package / CaseSOT23-6, package designator DBV
InterfaceSPI-compatible digital output
Temperature Resolution12-bit + sign, 0.0625 °C
Temperature Input Range-40 to +125 °C; electrical characteristics, TA=-40°C to +125°C, V+=2.7V to 5.5V
Temperature Accuracytyp ±0.5 °C, max ±1.5 °C; -25°C to +85°C
Temperature Accuracytyp ±1.0 °C, max ±2.0 °C; -40°C to +125°C
Temperature Accuracytyp ±1.5 °C; -40°C to +150°C
Temperature Error vs Supplymin -0.3 °C/V, typ 0.1 °C/V, max +0.3 °C/V
Digital Temperature Resolution±0.0625 °C
Input High Voltagemin 0.7 × V+ V; VIH digital input logic level
Input Low Voltagemax 0.3 × V+ V; VIL digital input logic level
Input Currentmax ±1 µA; SO, SCK, CS; 0V ≤ VIN ≤ V+
Output Low Voltagemax 0.4 V; SO, ISINK=3 mA
Output High Voltagemin V+ - 0.4 V; SO, ISOURCE=2 mA
Digital Output Resolution12 bits
Input Capacitancetyp 2.5 pF; SO, SCK, CS
Conversion Timetyp 240 ms, max 320 ms; 12-bit conversion
Conversion Periodtyp 480 ms, max 640 ms; 12-bit conversion; period between conversion starts
Supply Voltage Operating Range2.7 to 5.5 V
Quiescent Currenttyp 35 µA, max 50 µA; serial bus inactive
Shutdown Currenttyp 0.1 µA, max 1 µA; TMP121, serial bus inactive
Specified Temperature Range-40 to +125 °C
Operating Temperature Range-55 to +150 °C
Storage Temperature Range-60 to +150 °C
Thermal Resistance200 °C/W; θJA, SOT23-6 surface-mount
Absolute Maximum Supply Voltage7 V; power supply V+
Absolute Maximum Input Voltage-0.3 to +7 V; applies to all TMP121 and TMP123 input voltages
Absolute Maximum Input Current10 mA
Absolute Maximum Operating Temperature Range-55 to +150 °C
Absolute Maximum Storage Temperature Range-60 to +150 °C
Maximum Junction Temperature+150 °C; TJ max
Lead Temperature+300 °C; soldering
Temperature Register Width16-bit signed read-only register; stores most recent conversion output
Temperature Data FormatBinary two's complement, sign bit first; 16-bit data word output
Power-up Temperature Register Value0 °C; following power-up or reset until first conversion is complete
SCK Periodmin 100 ns; SPI timing parameter t1
SCK Falling Edge to Output Data Delaymax 30 ns; SPI timing parameter t2
CS to Rising Edge SCK Setup Timemin 40 ns; SPI timing parameter t3
CS to Output Data Delaymax 30 ns; SPI timing parameter t4
CS Rising Edge to Output High Impedancemax 30 ns; SPI timing parameter t5
Recommended Bypass Capacitor0.1 µF; supply bypass capacitor recommended; no external components required for operation
Pin Count6 pins; SOT23-6 package
TMP121 PinoutPin 1 NC, Pin 2 GND, Pin 3 V+, Pin 4 SCK, Pin 5 CS, Pin 6 SO; top view SOT23-6
Datasheet Statusrequest_only

Product Overview

TMP121 is a Texas Instruments digital temperature sensor with an SPI-compatible serial output. It stores the most recent conversion in a 16-bit signed read-only temperature register and outputs a 16-bit data word in binary two's complement format with the sign bit first. Following power-up or reset, the temperature register reads 0 °C until the first conversion is complete.

The device supports 12-bit digital output resolution with 0.0625 °C temperature resolution. Accuracy is specified as typical ±0.5 °C and maximum ±1.5 °C from -25 °C to +85 °C, and typical ±1.0 °C and maximum ±2.0 °C across -40 °C to +125 °C. The 12-bit conversion time is 240 ms typical and 320 ms maximum.

TMP121 is supplied in a 6-pin SOT23-6 package, designator DBV. The top-view pinout is NC, GND, V+, SCK, CS, and SO. Operation uses a 2.7 to 5.5 V supply, and a 0.1 µF supply bypass capacitor is recommended while no external components are required for operation.

Key Features

  • SPI-compatible digital temperature output
  • 12-bit plus sign temperature resolution
  • 0.0625 °C digital temperature step size
  • 2.7 V to 5.5 V supply operation
  • 35 µA typical quiescent current
  • 0.1 µA typical shutdown current
  • 240 ms typical 12-bit conversion time
  • 16-bit signed read-only temperature register
  • Binary two's-complement temperature data format
  • SOT23-6 DBV package with six pins

Typical Applications

  • SPI digital temperature measurement
  • Board-level thermal sensing
  • Low-current temperature monitoring
  • SOT23-6 compact sensor designs
  • 2.7 V to 5.5 V systems
  • Two's-complement temperature data handling

Procurement Notes

When requesting a quote for TMP121, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.

If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.

For analog and signal-chain sourcing, supply voltage, bandwidth, accuracy, noise level, package, temperature grade, input/output configuration and qualification requirements should be verified before approval.

FAQ

What interface does the TMP121 use for temperature data?

The TMP121 provides an SPI-compatible digital output. Its serial interface uses SCK, CS, and SO pins, and the temperature data is output as a 16-bit word in binary two's-complement format with the sign bit first.

What temperature resolution is specified for the TMP121?

The TMP121 has 12-bit plus sign temperature resolution with a 0.0625 °C step size. The datasheet also lists digital output resolution as 12 bits and digital temperature resolution as ±0.0625 °C.

What supply voltage range does the TMP121 support?

The specified operating supply voltage range is 2.7 V to 5.5 V. The absolute maximum supply voltage for the V+ power supply pin is 7 V.

What package and pinout are used by the TMP121?

The TMP121 is supplied in a SOT23-6 package with package designator DBV. The top-view pinout is Pin 1 NC, Pin 2 GND, Pin 3 V+, Pin 4 SCK, Pin 5 CS, and Pin 6 SO.

Technical Review & Sourcing Note

Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: July 8, 2026.

This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.

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