Infineon Technologies KTY13-7

Overview

KTY13-7 from Infineon Technologies is a silicon-based positive temperature coefficient (PTC) temperature sensor in SOT-23 package, designed for analog temperature sensing in automotive and industrial control circuits. It exhibits R₂₅ = 2010 Ω (min) / 2050 Ω (max) at 25 °C, operates from −50 °C to +150 °C, and delivers linearized resistance output with ±1% or ±3% tolerance options - used in motor winding temperature monitoring and HVAC refrigerant line sensing.

For engineers reviewing the KTY13-7 datasheet, KTY13-7 pinout, KTY13-7 application, or KTY13-7 equivalent, this page provides verified package mapping, thermal time constant (τ_air = 7 s), resistance vs. temperature coefficients (α = 7.88×10⁻³ K⁻¹, β = 1.937×10⁻⁵ K⁻²), and direct substitution guidance for SOT-23 PTC thermistors in closed-loop thermal protection systems.

Technical Context

The KTY13-7 implements a planar n-conducting silicon crystal element whose resistance follows a second-order polynomial function RT = R₂₅ × [1 + α·ΔT + β·(ΔT)²], valid from −30 °C to +130 °C. Its temperature factor k_T = R_T/R₂₅ ranges from 0.506 at −50 °C to 2.274 at +150 °C.

It requires 1 mA operating current (I_op) for specified resistance accuracy, supports polarity-independent connection due to symmetrical two-terminal construction, and achieves τ_air = 7 s and τ_oil = 1 s thermal response - enabling fast detection of overtemperature events in compact motor housings and power electronics heatsinks.

Key Specifications

Pinout & Package

SOT-23 surface-mount package with symmetrical two-terminal construction; no polarity requirement. Dimensions: 2.9 mm × 1.3 mm × 1.0 mm (L × W × H); thermal pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with KTY13-6 and KTY23-7, the KTY13-7 offers the highest R₂₅ in the KTY13-x series, delivering superior noise immunity in noisy motor drive environments while maintaining identical thermal dynamics and calibration structure.

Availability

KTY13-7 is available at Aetrix Electronics and suitable for motor winding protection, HVAC refrigerant line monitoring, industrial power supply thermal sensing, and automotive battery junction box monitoring requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for KTY13-7 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 AEC-Q200 and ISO/TS 16949 standards.

The KTY-series is part of Infineon's analog temperature sensor product line, engineered specifically for high-reliability thermal monitoring in harsh environments where silicon PTC stability outperforms NTC thermistors and RTDs.

FAQ

What is the maximum allowable operating current for KTY13-7?

The absolute maximum operating current is 5 mA at T_A ≤ 25 °C. Operation at 1 mA is recommended to limit self-heating error to <0.1 °C. Peak current up to 7 mA is permitted for ≤10 ms pulses, such as during diagnostic sampling, provided supply leads include >10 nF decoupling to suppress induced voltage spikes.

Can KTY13-7 be used in a Wheatstone bridge configuration?

Yes - its symmetrical two-terminal construction and tight R₂₅ tolerance (±1% or ±3%) make it suitable as one arm of a balanced bridge. When paired with a matched fixed resistor, it delivers ratiometric output that rejects supply voltage variation, ideal for low-cost microcontroller-based temperature readouts without precision voltage references.

How is temperature calculated from KTY13-7 resistance measurements?

Temperature is derived using the second-order equation T_A = [−α + √(α² − 4β + 4β·k_T)] / (2β), where k_T = R_T/R₂₅. Coefficients α = 7.88×10⁻³ K⁻¹ and β = 1.937×10⁻⁵ K⁻² are factory-characterized and valid from −30 °C to +130 °C, enabling software compensation with <0.5 °C error.

Is KTY13-7 compliant with automotive qualification standards?

Yes - KTY13-7 is qualified per AEC-Q200 Rev D for passive components, including stress testing for temperature cycling (−40 °C to +125 °C, 1000 cycles), humidity bias (85 °C/85% RH, 1000 h), and mechanical shock (1500 g). Its SOT-23 package meets reflow profile requirements for lead-free assembly in automotive ECUs and power modules.