RK73B1ELTP121J KOA Speer Resistor (Resistor Chip) In Stock
The KOA Speer RK73B1ELTP121J is a 120 Ω thick-film surface-mount resistor rated at 1/16 W with ±5 % tolerance. This ultra-compact 0402 package (1 mm × 0.5 mm) is engineered for cost-sensitive consumer electronics, IoT devices, and mobile computing applications demanding minimal PCB footprint. Global stock availability guarantees immediate shipment worldwide.
- Manufacturer
- KOA Speer
- Package
- Resistor Chip
- Pin Count
- 2
- Lifecycle
- ACTIVE
- Datasheet
- RK73B1ELTP121J Datasheet PDF
- Category
- Resistor
- Price
- From $0.0070(MOQ 1)
- Temp Range
- -55.0°C to 155.0°C
- RoHS
- Non-compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of RK73B1ELTP121J?
- 120 Ω resistance in ultra-compact 0402 package (1 mm × 0.5 mm × 0.35 mm)
- 1/16 W power rating ideal for low-power IoT and wearable applications
- ±5% tolerance for general-purpose biasing and pull-up network applications
What is RK73B1ELTP121J used for?
The RK73B1ELTP121J excels in ultra-dense wireless modules, smartwatch circuits, and IoT sensor boards where PCB area is at a premium. Its minimal 1/16 W dissipation supports low-power microcontroller designs, wireless charging receiver networks, and battery-powered portable electronics requiring strict BOM cost optimization and minimal thermal dissipation.
What are the specifications of RK73B1ELTP121J?
| Pbfree Code | No |
| Reach Compliance Code | Not Compliant |
| YTEOL | 9 |
| Construction | Rectangular |
| JESD-609 Code | e0 |
| Mounting Feature | SURFACE MOUNT |
| Package Height | 0.35mm |
| Package Length | 1mm |
| Package Shape | RECTANGULAR PACKAGE |
| Package Style | SMT |
| Package Width | 0.5mm |
| Packing Method | TR, PUNCHED PAPER, 7 INCH |
| Rated Power Dissipation (P) | 0.1W |
| Rated Temperature | 70°C |
| Reference Standard | AEC-Q200 |
| Resistance | 120Ω |
| Resistor Type | FIXED RESISTOR |
| Size Code | 0402 |
| Surface Mount | YES |
| Technology | METAL GLAZE/THICK FILM |
| Temperature Coefficient | 200ppm/°C |
| Terminal Finish | Tin/Lead (Sn90Pb10) - with Nickel (Ni) barrier |
| Terminal Shape | WRAPAROUND |
| Tolerance | 5% |
| Working Voltage | 75V |
| Package | Resistor Chip |
Compliance & Regulatory
| RoHS Status | Non-compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8533.21.00.30 |
| Country of Origin | Japan, Mainland China, Malaysia |
Where can I find the RK73B1ELTP121J datasheet?
RK73B1ELTP121J Datasheet DownloadOfficial datasheet from KOA Speer
What are equivalent replacements for RK73B1ELTP121J?
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What are the power and thermal characteristics of the RK73B1ELTP121J 0402 resistor in mobile computing designs?
The RK73B1ELTP121J dissipates 1/16 W (62.5 mW) maximum at 25°C ambient temperature. For typical mobile phone circuits operating at 3.3 V with 10 mA through the 120 Ω resistor, the actual dissipation is only 12 mW, well below the 62.5 mW rating. The 0402 form factor (1 mm × 0.5 mm) generates surface temperature rise of only 5 to 8 degrees Celsius above ambient, enabling safe placement adjacent to sensitive RF components without thermal isolation.
How does the 0402 package enable ultra-dense Bluetooth LE module layouts with optimal component density?
The 0402 resistor occupies only 0.5 mm² of PCB area; a complete 32-resistor biasing network for a Bluetooth Low Energy SoC can fit within a 1 cm × 1.5 cm area, including traces and vias. Compared to 0603 resistors (1.6 mm × 0.8 mm = 1.28 mm² each), the 0402 reduces the network footprint by approximately 60 %, enabling entire modules to shrink from 2 cm × 3 cm to 1.5 cm × 2 cm form factors for wearable applications.
When is the RK73B1ELTP121J 120 Ω ±5% resistor preferred over precision ±1% alternatives for consumer device cost optimization?
In mass-produced consumer IoT devices targeting $5 to $10 wholesale price points, every cent of component cost is critical. The RK73B1ELTP121J costs 40 to 50 % less than a precision 120 Ω ±1 % alternative, while the ±5 % tolerance is sufficient for pull-up resistors (which tolerate ±20 % drift without function loss) and LED current-limiting (where ±10 % brightness variation is imperceptible to users). A 100,000-unit design saves $8,000 to $12,000 in component cost.
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Why Buy from FindMyChip
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.
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $0.0432 | $0.04 |
| 742+ | $0.0162 | $12.02 |
| 3087+ | $0.0081 | $25.00 |
| 24692+ | $0.0070 | $172.84 |
In Stock · 24h Response · Worldwide Shipping
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