SMCJ18CA-TP Equivalent & Substitute Parts

Part Overview

The SMCJ18CA-TP is a transient voltage suppressor (TVS) diode manufactured by Micro Commercial Co, designed for general-purpose overvoltage protection in surface-mount applications. This bidirectional Zener diode operates with an 18V reverse standoff voltage and provides 29.2V clamping at peak pulse current, delivering 1500W peak pulse power dissipation in a DO-214AB (SMC) package. The part is active and ROHS3 compliant with unlimited moisture sensitivity rating. Equivalent and substitute parts are identified based on matching electrical performance parameters and package compatibility to support procurement flexibility and supply chain continuity.

Key Parameters

Parameter	Value
Voltage - Reverse Standoff (Typ)	18V
Voltage - Breakdown (Min)	20V
Voltage - Clamping (Max) @ Ipp	29.2V
Current - Peak Pulse (10/1000µs)	51.4A
Power - Peak Pulse	1500W
Package / Case	DO-214AB, SMC
Mounting Type	Surface Mount
Operating Temperature Range	-55°C ~ 175°C (TJ)
Type	Zener
Bidirectional Channels	1
RoHS Status	ROHS3 Compliant

Substitute Part Grouping Explanation

Substitute parts for the SMCJ18CA-TP are classified into two categories based on electrical parameter alignment:

Direct Substitutes maintain identical electrical specifications across all critical parameters: 18V reverse standoff voltage, 20V minimum breakdown voltage, 29.2V maximum clamping voltage, and 51.4A peak pulse current at 1500W power dissipation. These parts differ only in manufacturer, packaging format (Tape & Reel vs. Cut Tape), or minor suffix variations that do not affect electrical performance. Direct substitutes include SMCJ18CA (EVVO Semi), SMCJ18CA-13-F (Diodes Incorporated), and SMCJ18CA-E3/57T (Vishay General Semiconductor).

Similar Substitutes maintain the core voltage parameters (18V standoff, 20V breakdown, 29.2V clamping) but differ in peak pulse current and power dissipation ratings. These parts are suitable for applications where higher current handling or power dissipation capability is acceptable or beneficial. Similar substitutes include 5.0SMDJ18CA (MDE Semiconductor, 172A/5kW), SMCJ18CA-TR (STMicroelectronics, 254A/1500W), SMDJ18CA (Alpha & Omega, 102.8A/3kW), SMDJ18CA-T7 (Littelfuse, 102.7A/3kW), and SMLJ18CA (Bourns, 102.8A/3kW).

Parameter Comparison

Manufacturer Part Number	Manufacturer	Voltage - Reverse Standoff (Typ)	Voltage - Breakdown (Min)	Voltage - Clamping (Max) @ Ipp	Current - Peak Pulse (10/1000µs)	Power - Peak Pulse	Package / Case	Operating Temperature	RoHS Status
SMCJ18CA-TP	Micro Commercial Co	18V	20V	29.2V	51.4A	1500W	DO-214AB, SMC	-55°C ~ 175°C	ROHS3 Compliant
SMCJ18CA	EVVO Semi	18V	20V	29.2V	51.4A	1500W	DO-214AB, SMC	-55°C ~ 150°C	ROHS3 Compliant
SMCJ18CA-13-F	Diodes Incorporated	18V	20V	29.2V	51.4A	1500W	DO-214AB, SMC	-55°C ~ 150°C	ROHS3 Compliant
SMCJ18CA-E3/57T	Vishay General Semiconductor - Diodes Division	18V	20V	29.2V	51.4A	1500W	DO-214AB, SMC	-55°C ~ 150°C	ROHS3 Compliant
5.0SMDJ18CA	MDE Semiconductor Inc	18V	20V	29.2V	172A	5000W	DO-214AB, SMC	-55°C ~ 150°C	ROHS3 Compliant
SMCJ18CA-TR	STMicroelectronics	18V	20V	39.3V	254A (8/20µs)	1500W	DO-214AB, SMC	-55°C ~ 150°C	ROHS3 Compliant
SMDJ18CA	Alpha & Omega Semiconductor Inc.	18V	20V	29.2V	102.8A	3000W	DO-214AB, SMC	-55°C ~ 150°C	ROHS3 Compliant
SMDJ18CA-T7	Littelfuse Inc.	18V	20V	29.2V	102.7A	3000W	DO-214AB, SMC	-65°C ~ 150°C	ROHS3 Compliant
SMLJ18CA	Bourns Inc.	18V	20V	29.2V	102.8A	3000W	DO-214AB, SMC	-55°C ~ 150°C	ROHS3 Compliant

Engineering Selection Recommendations

Direct Substitutes (SMCJ18CA, SMCJ18CA-13-F, SMCJ18CA-E3/57T) are electrically equivalent to SMCJ18CA-TP and suitable for one-to-one replacement in applications requiring 51.4A peak pulse current and 1500W power dissipation. All direct substitutes maintain ROHS3 compliance and unlimited moisture sensitivity rating. The primary consideration is operating temperature range: SMCJ18CA-TP supports -55°C to 175°C, while direct substitutes from EVVO Semi, Diodes Incorporated, and Vishay support -55°C to 150°C. Selection of direct substitutes is appropriate when the application operating temperature does not exceed 150°C.

Similar Substitutes with Higher Current Ratings (SMDJ18CA, SMDJ18CA-T7, SMLJ18CA) provide 102.7A to 102.8A peak pulse current and 3000W power dissipation while maintaining identical voltage parameters. These parts are suitable for applications where higher transient current handling is required or where design margin is desired. All maintain ROHS3 compliance and -55°C to 150°C operating temperature range.

Higher Power Substitute (5.0SMDJ18CA) delivers 172A peak pulse current and 5000W power dissipation, appropriate for high-energy transient suppression applications. This part maintains identical voltage specifications and ROHS3 compliance.

Clamping Voltage Variant (SMCJ18CA-TR from STMicroelectronics) exhibits 39.3V maximum clamping voltage compared to 29.2V in the primary part, with significantly higher peak pulse current (254A at 8/20µs pulse). This part is suitable only when higher clamping voltage is acceptable in the application circuit.

All substitute parts are active products with ROHS3 compliance and REACH unaffected or affected status as specified. Selection should prioritize parts matching the application's peak pulse current requirement and operating temperature range.

Frequently Asked Questions (FAQ)

Q: Can SMCJ18CA from EVVO Semi directly replace SMCJ18CA-TP?

A: Yes, SMCJ18CA from EVVO Semi is a direct electrical equivalent with identical voltage and current specifications. The primary difference is operating temperature range: SMCJ18CA supports -55°C to 150°C versus SMCJ18CA-TP at -55°C to 175°C. Direct substitution is appropriate for applications operating within -55°C to 150°C.

Q: What is the difference between direct substitutes and similar substitutes?

A: Direct substitutes maintain all electrical parameters identical to SMCJ18CA-TP, including 51.4A peak pulse current and 1500W power dissipation. Similar substitutes maintain voltage specifications but offer higher peak pulse current (102.7A to 172A) and power dissipation (3000W to 5000W), providing greater transient suppression capability.

Q: Can I use SMDJ18CA-T7 (102.7A) in place of SMCJ18CA-TP (51.4A)?

A: Yes. SMDJ18CA-T7 maintains identical voltage parameters (18V standoff, 20V breakdown, 29.2V clamping) and provides higher peak pulse current and power dissipation. This substitution is appropriate when the application can accommodate the higher current rating or when additional design margin is desired. Operating temperature range is -65°C to 150°C.

Q: What is the significance of the clamping voltage parameter?

A: Clamping voltage determines the maximum voltage the TVS diode allows across the protected circuit during a transient event. SMCJ18CA-TP clamps at 29.2V maximum. SMCJ18CA-TR from STMicroelectronics clamps at 39.3V. Selection depends on the protected circuit's voltage tolerance; lower clamping voltage provides better protection but requires higher current handling capability.

Q: Are all substitute parts ROHS3 compliant?

A: Yes, all substitute parts listed are ROHS3 compliant. REACH status varies by manufacturer; verify REACH compliance requirements for your specific application and supply chain.

Q: Does packaging format affect electrical performance?

A: No. Packaging format differences (Tape & Reel vs. Cut Tape & Digi-Reel) do not affect electrical performance. Selection is based on procurement and assembly process requirements.

Q: What operating temperature range should I consider for substitution?

A: SMCJ18CA-TP supports -55°C to 175°C. Direct substitutes support -55°C to 150°C. SMDJ18CA-T7 supports -65°C to 150°C. Select a substitute with operating temperature range meeting or exceeding your application requirements.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message