Panasonic ERJ-2RKF4021X 4.02K ohm 1% 0.1W 0402 SMD Thick Film Resistors 80 PCS NOS

Genuine Panasonic ERJ-2RKF4021X precision thick-film surface-mount chip resistors featuring a 4.02K ohm (4,020 ohm) resistance value, 1% tolerance, and 0.1W (1/10 watt) power rating. These miniature 0402 (1005 metric) resistors belong to Panasonic's ERJ-2RK precision resistor family, designed for compact electronic circuits requiring accurate resistance values, reliable operation, and efficient printed circuit board assembly.
The 4.02K ohm resistance value belongs to the E96 precision resistor series, providing a more specific resistance selection than common E12 or E24 standard values.
These resistors are suitable for voltage dividers, amplifier bias networks, signal conditioning, feedback circuits, filtering networks, communications electronics, industrial controls, automotive electronic assemblies, power management circuits, and general component-level repair.
Panasonic's precision thick-film construction uses a resistive element deposited onto a ceramic substrate with protective coatings and solderable terminals. The compact 0402 package is especially useful in densely populated circuit boards where available space is limited.
TECHNICAL SPECIFICATIONS:
- Resistance: 4.02K ohms (4,020 ohms)
- Resistance Tolerance: 1%
- Power Rating: 0.1W (1/10 watt)
- Package: 0402 SMD (1005 metric)
- Dimensions: 1.0 x 0.5 mm
- Maximum Component Height: 0.40 mm
- Construction: Precision Thick Film
- Temperature Coefficient: ±100 ppm/°C
- Operating Temperature: -55°C to +155°C
- Automotive Qualification: AEC-Q200
- Series: Panasonic ERJ-2RK
- Resistance Series: E96
- Mounting Type: Surface Mount
- Termination Count: 2
- Manufacturer Date Code: 2125 (2021, Week 25)
- Country of Origin: China (CN, original supplier label)
- Original Packaging: Distributor-labeled electronic component stock
LIFECYCLE: ACTIVE
- HISTORICAL BACKGROUND: Panasonic traces its origins to 1918, when Konosuke Matsushita founded the Matsushita Electric Housewares Manufacturing Works in Osaka, Japan. The business initially produced electrical accessories and gradually expanded into a major international manufacturer of consumer electronics, industrial equipment, electrical systems, and electronic components. Matsushita Electric Industrial Co., Ltd. formally adopted the Panasonic Corporation name in 2008.
Panasonic became an important supplier of passive electronic components, including capacitors, resistors, inductors, and other devices used throughout consumer, industrial, automotive, and communications electronics.
During the late twentieth century, the electronics industry increasingly transitioned from traditional through-hole components to surface-mount technology. This change allowed manufacturers to reduce circuit board dimensions, increase component density, improve automated assembly efficiency, and develop increasingly compact electronic equipment.
Thick-film chip resistors became widely adopted during this transition because they offered an economical method of producing stable, standardized resistance values in miniature packages. These resistors generally use a resistive film deposited onto a ceramic substrate, with protective coatings and metallic terminations designed for solder attachment.
Panasonic developed its extensive ERJ family of chip resistors to support surface-mount manufacturing and the growing requirements of modern electronics. The family includes general-purpose resistors, precision thick-film components, high-power configurations, and specialized resistors for demanding electronic applications.
The ERJ-2RK series represents Panasonic's miniature precision thick-film resistor technology in the 0402 package. The series provides 1% resistance tolerance and standardized resistance values suitable for compact printed circuit boards.
The ERJ-2RKF4021X provides a precision 4.02K ohm resistance value with a 0.1W power rating and a temperature coefficient of ±100 ppm/°C. The component measures approximately 1.0 x 0.5 mm, illustrating the miniaturization of passive components used in modern electronic assemblies.
Precision resistance values such as 4.02K ohms are particularly useful in voltage reference networks, analog signal processing, feedback circuits, measurement electronics, and other applications where engineers require a specific resistance value.
The development of miniature precision resistors helped support advances in portable electronics, telecommunications equipment, industrial controllers, computers, automotive electronics, and modern electronic instrumentation.
Panasonic's ERJ resistor technology remains relevant for electronic manufacturing, maintenance, and component-level repair, particularly when exact resistance values and standardized surface-mount dimensions are required.