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

What are the key features of NT731JTTD103J3500J?

  • 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

What is NT731JTTD103J3500J used for?

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.

What are the specifications of NT731JTTD103J3500J?

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

Where can I find the NT731JTTD103J3500J datasheet?

NT731JTTD103J3500J Datasheet Download

Official datasheet from KOA Speer

What are equivalent replacements for NT731JTTD103J3500J?

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.

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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