RC1005F1781CS Equivalent & Substitute Parts Reference

Part Overview

The RC1005F1781CS is a 1.78 kOhms ±1% thick film chip resistor manufactured by Samsung Electro-Mechanics in 0402 (1005 Metric) package format. This surface mount device is rated for 0.063W (1/16W) power dissipation and operates across the temperature range of -55°C to 155°C. The component features moisture resistance and is ROHS3 compliant with MSL Level 1 (unlimited moisture sensitivity rating). The part is currently in active production status with 1137 units available in inventory. Equivalent and substitute parts are identified to support procurement flexibility, design redundancy, and supply chain continuity when the primary part becomes unavailable or when design requirements necessitate alternative component selections.

Key Parameters

Parameter	Value
Resistance	1.78 kOhms
Tolerance	±1%
Power Rating	0.063W (1/16W)
Package / Case	0402 (1005 Metric)
Composition	Thick Film
Temperature Coefficient	±100ppm/°C
Operating Temperature Range	-55°C ~ 155°C
Moisture Sensitivity Level	1 (Unlimited)
RoHS Status	ROHS3 Compliant
Number of Terminations	2

Substitute Part Grouping Explanation

Substitution eligibility for the RC1005F1781CS is determined by strict equivalence across the following critical parameters:

Mandatory Matching Parameters:

Resistance value: 1.78 kOhms
Tolerance: ±1%
Package / Case: 0402 (1005 Metric)
Composition: Thick Film
Temperature Coefficient: ±100ppm/°C
Operating Temperature Range: -55°C ~ 155°C
Number of Terminations: 2
RoHS Status: ROHS3 Compliant
Moisture Sensitivity Level: 1 (Unlimited)

Allowable Variation Parameter:

Power Rating: Substitutes rated at 0.063W (1/16W) or higher are acceptable. Higher power ratings provide equivalent or superior thermal performance in the same package footprint.

Substitute Classification:

Direct Equivalents (identical across all parameters including power rating):

CR0402-FX-1781GLF (Bourns Inc.)
RC0402FR-071K78L (YAGEO)

Upgrade Substitute (higher power rating, same package):

ERJ-2RKF1781X (Panasonic Electronic Components) — 0.1W (1/10W) rating with Automotive AEC-Q200 qualification

Similar Substitutes (identical electrical parameters with additional automotive qualification):

AC0402FR-071K78L (YAGEO)
CRCW04021K78FKED (Vishay Dale)
RMCF0402FT1K78 (Stackpole Electronics Inc)

All substitute parts maintain identical resistance, tolerance, package dimensions, temperature coefficient, and operating temperature range. Differences in power rating and automotive certifications do not affect functional interchangeability in standard applications.

Parameter Comparison

Manufacturer Part Number	Manufacturer	Resistance	Tolerance	Power (Watts)	Package	Temp Coeff	Operating Temp	MSL	RoHS	Features	Inventory
RC1005F1781CS	Samsung Electro-Mechanics	1.78 kOhms	±1%	0.063W	0402	±100ppm/°C	-55°C ~ 155°C	1	ROHS3	Moisture Resistant	1137 Pcs
CR0402-FX-1781GLF	Bourns Inc.	1.78 kOhms	±1%	0.063W	0402	±100ppm/°C	-55°C ~ 155°C	1	ROHS3	—	17582 Pcs
RC0402FR-071K78L	YAGEO	1.78 kOhms	±1%	0.063W	0402	±100ppm/°C	-55°C ~ 155°C	1	ROHS3	Moisture Resistant	24941 Pcs
ERJ-2RKF1781X	Panasonic Electronic Components	1.78 kOhms	±1%	0.1W	0402	±100ppm/°C	-55°C ~ 155°C	1	ROHS3	Automotive AEC-Q200	140229 Pcs
AC0402FR-071K78L	YAGEO	1.78 kOhms	±1%	0.063W	0402	±100ppm/°C	-55°C ~ 155°C	1	ROHS3	Automotive AEC-Q200, Moisture Resistant	10965 Pcs
CRCW04021K78FKED	Vishay Dale	1.78 kOhms	±1%	0.063W	0402	±100ppm/°C	-55°C ~ 155°C	1	ROHS3	Automotive AEC-Q200	73716 Pcs
RMCF0402FT1K78	Stackpole Electronics Inc	1.78 kOhms	±1%	0.063W	0402	±100ppm/°C	-55°C ~ 155°C	1	ROHS3	Automotive AEC-Q200	48706 Pcs

Engineering Selection Recommendations

For Standard Industrial Applications: CR0402-FX-1781GLF (Bourns Inc.) or RC0402FR-071K78L (YAGEO) are direct functional equivalents with identical electrical and thermal specifications. Both parts maintain ROHS3 compliance and MSL Level 1 rating. Selection between these options is based on procurement availability and supply chain logistics.

For Automotive or High-Reliability Applications: AC0402FR-071K78L, CRCW04021K78FKED, or RMCF0402FT1K78 are suitable when Automotive AEC-Q200 qualification is required. These parts maintain identical electrical performance while providing automotive-grade manufacturing and testing protocols.

For Thermal Margin Enhancement: ERJ-2RKF1781X (Panasonic Electronic Components) provides a higher power rating of 0.1W (1/10W) in the identical 0402 package footprint. This upgrade substitute is applicable when design margins require increased thermal headroom or when operating conditions approach the 0.063W limit of the primary part.

Compliance Verification: All listed substitute parts maintain ROHS3 compliance and MSL Level 1 rating, ensuring compatibility with standard PCB assembly processes and environmental requirements. No additional qualification or testing is required for direct substitution within the same application category.

Frequently Asked Questions (FAQ)

Q: Can CR0402-FX-1781GLF be used as a direct replacement for RC1005F1781CS?

A: Yes. CR0402-FX-1781GLF is a direct equivalent. Both parts share identical resistance (1.78 kOhms), tolerance (±1%), power rating (0.063W), package (0402), temperature coefficient (±100ppm/°C), operating temperature range (-55°C ~ 155°C), and RoHS compliance. Physical dimensions and termination count are identical.

Q: What is the difference between the direct equivalents and the automotive-qualified substitutes?

A: Direct equivalents (CR0402-FX-1781GLF, RC0402FR-071K78L) match all electrical and thermal specifications of the RC1005F1781CS. Automotive-qualified substitutes (AC0402FR-071K78L, CRCW04021K78FKED, RMCF0402FT1K78) provide identical electrical performance with additional AEC-Q200 certification for automotive applications. Electrical interchangeability is complete; the difference is in manufacturing and qualification protocols.

Q: Is ERJ-2RKF1781X compatible with designs specified for RC1005F1781CS?

A: Yes, with thermal margin improvement. ERJ-2RKF1781X maintains identical resistance, tolerance, package, and temperature range. The higher power rating (0.1W versus 0.063W) provides superior thermal performance in the same footprint. This upgrade substitute is applicable in all applications where the original part is specified.

Q: Are there any packaging differences between these substitute parts?

A: All substitute parts are available in 0402 (1005 Metric) package with identical physical dimensions (0.039" L x 0.020" W / 1.00mm x 0.50mm). Packaging format variations (Tape & Reel versus Cut Tape) do not affect component functionality or PCB assembly compatibility. Verify packaging format availability with your supplier based on assembly process requirements.

Q: Can I use these substitutes interchangeably on the same PCB assembly?

A: Yes. All listed substitute parts are mechanically and electrically interchangeable. They share identical package footprints, lead spacing, and electrical characteristics. PCB layout and assembly processes require no modification. Component selection can be made based on procurement availability, cost, and supply chain considerations.

Q: What is the significance of MSL Level 1 rating for these parts?

A: MSL Level 1 (Unlimited) indicates these components have unlimited shelf life and require no special moisture control during storage or handling. Standard PCB assembly processes and storage conditions are sufficient. No baking or desiccant storage is required prior to reflow soldering.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All listed substitute parts maintain ROHS3 compliance, ensuring compatibility with environmental regulations and customer requirements. No additional compliance documentation or testing is required for substitution.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message