NT731JTTD103J3500J KOA Speer Thermistor (Thermistors Chip) In Stock

KOA Speer NT731JTTD103J3500J is a 10 kΩ NTC chip thermistor in a compact 0603 SMT package (1.6 mm × 0.8 mm × 0.5 mm) for precision temperature sensing. ±5% resistance tolerance and REACH/RoHS-compliant lead-free construction ensure accurate, environmentally safe thermal monitoring. Available in 7-inch tape-and-reel from authorized distributors with worldwide shipping.

OBSOLETEThermistorVerified Jun 2026
Package / Visual Reference
NT731JTTD103J3500JThermistors Chip
Quick Facts
Manufacturer
KOA Speer
Package
Thermistors Chip
Pin Count
2
Lifecycle
OBSOLETE
Category
Thermistor
Price
From $0.2380(MOQ 5000)
Temp Range
-55.0°C to 125.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

Key Features

  • 10 kΩ NTC thermistor in a 0603 SMT package (1.6 × 0.8 × 0.5 mm) for space-efficient temperature sensing on compact PCBs
  • ±5% (J-grade) resistance tolerance provides consistent temperature accuracy across production lots, reducing calibration overhead in high-volume designs
  • REACH-compliant and RoHS lead-free construction with 7-inch tape-and-reel packaging supports automated SMT assembly and global regulatory compliance

Applications

The NT731JTTD103J3500J is used for thermal management in battery packs, power supplies, and consumer electronics where a 10 kΩ NTC thermistor at 25°C feeds a microcontroller ADC for over-temperature protection and fan speed control. Its 0603 form factor fits on densely populated PCBs in wearable devices, IoT sensors, and industrial control boards where larger through-hole thermistors would not fit. Lead-free construction and REACH compliance make it suitable for medical devices and automotive-adjacent applications requiring strict environmental certification.

Specifications

Pbfree CodeYes
Reach Compliance CodeCompliant
YTEOL0
JESD-609 Codee3
Mounting FeatureSURFACE MOUNT
Package Height0.5mm
Package Length1.6mm
Package StyleSMT
Package Width0.8mm
Packing MethodTR, PAPER, 7 INCH
Rated Power Dissipation (P)0.005W
Resistance10000Ω
Resistor TypeNTC THERMISTOR
Surface MountYES
TechnologyMETAL GLAZE/THICK FILM
Terminal FinishMATTE TIN OVER NICKEL
Terminal PlacementDUAL ENDED
Terminal ShapeWRAPAROUND
Thermal Sensitivity Index3500K
Thermistor ApplicationTEMPERATURE COMPENSATION
Tolerance5%
PackageThermistors Chip

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
ECCNEAR99
HTS Code8533.40.80.70

Datasheet

NT731JTTD103J3500J Datasheet Download

Official datasheet from KOA Speer

Alternate & Equivalent Parts

No known alternates. Submit an RFQ and our team can suggest alternatives.

Frequently Asked Questions

How do designers use the 10 kΩ NTC resistance of the NT731JTTD103J3500J with a microcontroller ADC for temperature measurement?

A typical voltage-divider circuit pairs the 10 kΩ NTC thermistor with a fixed 10 kΩ reference resistor connected between Vcc (3.3 V or 5 V) and ground, with the mid-point connected to an ADC input. At 25°C the output is near Vcc/2, and the voltage shifts as temperature changes according to the Steinhart-Hart equation. A 10-bit ADC provides approximately 0.1°C resolution near 25°C, sufficient for battery temperature cutoff and thermal throttling in consumer electronics.

What does the 0603 package size (1.6 mm × 0.8 mm) of the NT731JTTD103J3500J mean for PCB thermal coupling accuracy?

The 1.6 mm × 0.8 mm × 0.5 mm chip body allows the thermistor to be placed within 1 mm to 2 mm of the heat-generating component being monitored, reducing thermal lag compared to a bulkier through-hole sensor. On a 4-layer PCB, copper pour beneath the 0603 pads conducts heat from adjacent ICs directly to the thermistor, improving response time to within a few seconds for transient over-temperature events in power management designs.

When does the ±5% (J-grade) tolerance of the NT731JTTD103J3500J require factory calibration versus tighter-tolerance alternatives?

A ±5% resistance tolerance at 25°C corresponds to roughly ±1.2°C to ±2°C uncertainty depending on the thermistor's B-constant. For battery over-temperature cutoffs at 60°C with a ±5°C acceptable window, J-grade tolerance is adequate without individual calibration. Applications requiring better than ±0.5°C accuracy — such as medical diagnostics or precision HVAC controls — should use tighter ±1% (F-grade) or ±0.5% thermistors, accepting the higher per-unit cost.

Related Guides

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Factory-direct from China distributors, low MOQ
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About KOA Speer

KOA Speer is a leading electronic component manufacturer. FindMyChip sources KOA Speer ICs directly from authorized China distributors, offering competitive pricing and reliable stock.

AvailabilityIn Stock
Reference Price (USD)
From $0.2380
Buy from 1pc · Factory-direct pricing
Qty.Unit PriceExt. Price
5000+$0.2380$1190.00
pcs
Unit price: $0.2380 · Total: $1190.00

In Stock · 24h Response · Worldwide Shipping

Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

Response within 24 hours · Worldwide shipping

Their engineering team helped us find a pin-compatible alternative when our original MCU went EOL.

MR
Marco Rossi
CTO, AutoDrive Systems, Italy