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ADC reference / quiet 3.3 V
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    RBIAS = 150 kΩ, ±0.1%, low TCR
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           +-------- ADC_SENSE --> ADC input
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  NCU18XH103F6SRB      CF = 10 nF (optional)
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       Analog GND ---- Analog GND

• Required passive: RBIAS provides controlled excitation. Start with 150 kΩ at 3.3 V. The higher resistance intentionally trades ADC signal amplitude for lower self-heating.
• Optional filter: Begin with 10 nF ceramic from ADC_SENSE to analog ground, physically near the ADC input. This is an engineering example, not a thermistor-required decoupling capacitor; adjust against the ADC’s input acquisition specification and target sample rate.
• Reference: If supported by the ADC, excite the divider from the same reference used for conversion. That makes resistance extraction ratiometric and reduces sensitivity to reference/supply variation.
• ADC loading: Check input leakage and sample-and-hold settling. A buffer, longer acquisition time, or a different excitation scheme may be required. Never assume a high-value divider is compatible with an unspecified MCU ADC.
• 5 V systems: An example 270 kΩ bias resistor limits current to below 18.6 µA even as thermistor resistance approaches zero. Do not connect this node directly to a 3.3 V-only ADC: a cold or open thermistor can pull the node close to 5 V. Confirm Murata’s voltage derating before selecting any 5 V excitation.

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VADC = VEXC × RNTC / (RBIAS + RNTC)
RNTC = RBIAS × VADC / (VEXC − VADC)
INTC = VEXC / (RBIAS + RNTC)
PNTC = INTC² × RNTC
Estimated self-heating ΔT ≈ PNTC / δ

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T_K ≈ 1 / [1 / 298.15 + ln(RNTC / 10000) / 3380]
T_°C = T_K − 273.15

• Place for the intended thermal measurement. For ambient sensing, separate the NTC from regulators, processors, LEDs, and power resistors. For device-temperature sensing, place it close to the target thermal path; it measures its own temperature, not automatically the target’s junction temperature.
• Control copper thermal coupling. A broad plane connection can make the NTC track board temperature instead of air temperature. Choose narrow connections or thermal relief for isolation, or deliberate copper coupling for board/hotspot sensing; do not apply thermal isolation indiscriminately.
• Use a validated 0603 land pattern with balanced pads. Match pad and paste geometry to the actual Murata drawing and assembly process to reduce tombstoning. Exact current pad dimensions, height tolerance, and reflow profile remain unverified; the ABNTC-0603 drawing attached to this project is not acceptable evidence.
• Keep ADC routing quiet. Route ADC_SENSE away from switch nodes and fast digital edges, keep the high-impedance segment short, and return to quiet analog ground. Signal-current capacity is not the limiting factor here; high-current trace sizing and differential-pair routing do not apply to the NTC itself.
• Put the optional filter near the ADC. Ground it with a short local return. The NTC has no supply pin and therefore needs no local IC-style decoupling; ADC/reference decoupling follows the chosen converter’s datasheet.

1. Confusing a power rating with accurate temperature sensing. The verified historical 100 mW rating is not a usable precision measurement-power target. Excitation self-heating and nearby hot copper can dominate the measurement even when the component survives; validate the thermal error with the final board and enclosure.
2. Treating every “10 kΩ 0603 NTC” as interchangeable. R25 alone is insufficient: compare the whole R–T curve, beta interval, tolerances, dimensions, temperature limits, and qualification. A different curve requires firmware or analog-threshold updates, and historical versus current operating limits must be resolved before production.

• Murata, NCU18XH103F6SRB Product Search Data Sheet, last updated 2018/03/12; manufacturer-authored historical document used for the verified Murata specifications. 1810311132_Murata-Electronics-NCU18XH103F6SRB_C162670.pdf.
• Murata official product page: NCU18XH103F6SRB. Direct reading was unavailable; it is a manufacturer follow-up location, not cited evidence for current limits.
• Vishay, SMD 0603, Glass Protected NTC Thermistors, document 29056; indexed revision 27-May-2024. Manufacturer PDF. A web read reported a different revision date; the quoted technical values are specifically from the indexed 2024 revision, and the current revision must be checked before substitution approval.
• TDK B57332V6103F360, manufacturer product page, read 2026-10-07; webpage revision date not stated in the returned content.
• DigiKey, exact-MPN product listing, read 2026-10-07; primary distributor evidence for cut-tape MOQ and packaging.
• TTI, exact-MPN listing; JLCPCB, C162670 assembly listing; and Flux library distributor results, consulted 2026-10-07 for sourcing, not as replacements for manufacturer electrical specifications.