Infineon Technologies KT130

Overview

KT130 from Infineon Technologies is a silicon-based positive temperature coefficient (PTC) temperature sensor in SOT-23 package, designed for precision analog temperature sensing in air or liquid media. It exhibits R₂₅ = 1940–2060 Ω at 25 °C, operates from −50 °C to +150 °C, and delivers linearized resistance vs. temperature response via second-order polynomial characterization (α = 7.88×10⁻³ K⁻¹, β = 1.937×10⁻⁵ K⁻²). Used in motor winding protection and HVAC ambient sensing.

For engineers reviewing the KT130 datasheet, KT130 pinout, KT130 application, or KT130 equivalent, this page provides verified electrical parameters, thermal time constant (τ_air = 7 s), package mapping to SOT-23, and confirmed alternatives with documented resistance tolerance (±3%), operating voltage (25 V max), and symmetrical two-terminal construction.

Technical Context

The KT130 implements a planar n-conducting silicon crystal element whose resistance varies predictably with temperature per RT = R₂₅ × [1 + α·ΔT + β·(ΔT)²], valid from −30 °C to +130 °C. Its symmetrical two-terminal design eliminates polarity dependence and enables direct series connection into bias circuits.

With a typical thermal time constant of 7 s in air and 1 s in oil, it supports rapid thermal tracking in dynamic environments. Absolute maximum ratings include 25 V operating voltage and 5 mA continuous operating current (7 mA peak, 10 ms), requiring external capacitor protection (>10 nF) when used with long supply leads.

Key Specifications

Pinout & Package

KT130 is housed in a standard SOT-23 surface-mount package with two terminals. Pin 1 and Pin 2 are electrically identical due to symmetrical construction - no polarity sensitivity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PTC temperature sensing applications.

Compared with KT130, KTY 13-6 offers marginally tighter R₂₅ tolerance but identical performance envelope, while KT 110 trades SOT-23 miniaturization for TO-92 mechanical ruggedness and reduced thermal responsiveness in air.

Availability

KT130 is available at Aetrix Electronics and suitable for motor protection, HVAC control, automotive coolant monitoring, and power supply thermal foldback requiring stable component supply across industrial and automotive production cycles.

Supply support for KT130 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, sensor, and automotive ICs, with global manufacturing and quality certification to ISO/TS 16949.

The KT- and KTY-series are Infineon's dedicated line of silicon PTC temperature sensors, engineered for high-stability analog temperature measurement in harsh thermal environments where reliability and long-term drift (<0.1%/K) are critical.

FAQ

Is KT130 polarity-sensitive?

No. KT130 uses symmetrical two-terminal construction with identical electrical behavior at both pins. It can be installed in either orientation without affecting resistance measurement or thermal response. This eliminates orientation errors during automated SMT placement and simplifies schematic symbol design.

What is the recommended bias current for KT130?

The specified test condition is I_op = 1 mA, and maximum continuous current is 5 mA. To minimize self-heating error (<0.1 °C), use 0.5–1 mA with a series bias resistor. At 5 mA, power dissipation reaches 5.15 mW (at R₂₅ = 2060 Ω), which may induce measurable offset in still-air conditions.

Can KT130 be used in liquid immersion?

Yes - KT130 is rated for operation in liquids including oils and coolants. Its thermal time constant drops to 1 s in oil, enabling fast response. Ensure hermetic sealing of PCB traces and conformal coating if exposed to conductive or corrosive fluids; the SOT-23 package itself is not intrinsically sealed.

How is temperature calculated from KT130 resistance?

Use the second-order equation: R_T = R₂₅ × [1 + α·ΔT + β·(ΔT)²], where α = 7.88×10⁻³ K⁻¹, β = 1.937×10⁻⁵ K⁻². Solve for ΔT numerically or invert to T = 25 + [−α + √(α² − 4β(1 − R_T/R₂₅))]/(2β), valid from −30 °C to +130 °C.