SMAJ85C Equivalent & Substitute Parts

Part Overview

The SMAJ85C is a transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection in surface-mount applications. This part operates with an 85V reverse standoff voltage and provides clamping at 143.85V with a peak pulse current of 2.9A. The SMAJ85C is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement.

Key Parameters

Parameter	Value
Reverse Standoff Voltage (Typ)	85V
Breakdown Voltage (Min)	89.28V
Clamping Voltage (Max) @ Ipp	143.85V
Peak Pulse Current (10/1000µs)	2.9A
Peak Pulse Power	400W
Package / Case	DO-214AC (SMA)
Operating Temperature Range	-65°C ~ 150°C (TJ)
RoHS Status	ROHS3 Compliant
Moisture Sensitivity Level	1 (Unlimited)

Substitute Part Grouping Explanation

Substitution for the SMAJ85C is determined by the following critical parameters:

Reverse Standoff Voltage: Must be 85V (±tolerance)
Package / Case: Must be DO-214AC (SMA) for mechanical and thermal compatibility
Bidirectional Channels: Must be 1 (unidirectional operation)
Type: Must be Zener diode
RoHS Compliance: Must maintain ROHS3 Compliant status
Mounting Type: Must be Surface Mount

Substitute parts are grouped into two categories based on clamping voltage performance:

Group A (Lower Clamping Voltage): Parts with clamping voltage at or below 137V, suitable for applications with tighter voltage regulation requirements.

Group B (Higher Clamping Voltage): Parts with clamping voltage above 143V, suitable for applications requiring higher transient energy absorption.

Parameter Comparison

Part Number	Manufacturer	Reverse Standoff (V)	Breakdown Min (V)	Clamping Max @ Ipp (V)	Peak Pulse Current (A)	Peak Pulse Power (W)	Operating Temp (°C)	Product Status
SMAJ85C	Littelfuse Inc.	85	89.28	143.85	2.9	400	-65 ~ 150	Obsolete
SMAJ85CA	Meritek	85	94.4	137	2.92	400	-55 ~ 150	Active
SMA6J85CA-TR	STMicroelectronics	85	94	146	22.5 (8/20µs)	600	-55 ~ 175	Active
SMAJ85CA-13-F	Diodes Incorporated	85	94.4	137	2.9	400	-55 ~ 150	Active
SMAJ85CAE3/TR13	Microchip Technology	85	94.4	137	3.6	500	-65 ~ 150	Active
SMAJ85CE3/TR13	Microchip Technology	85	94.4	151	3.3	500	-65 ~ 150	Active
TV04A850JB-G	Comchip Technology	85	94.4	137	2.92	400	-55 ~ 150	Active

Engineering Selection Recommendations

All substitute parts listed maintain ROHS3 compliance and MSL 1 (Unlimited) moisture sensitivity rating, ensuring compatibility with standard manufacturing and storage conditions.

For direct replacement with minimal performance variation: SMAJ85CA-13-F (Diodes Incorporated) or TV04A850JB-G (Comchip Technology) provide equivalent clamping voltage (137V) and peak pulse current (2.9A–2.92A) to the original SMAJ85C, with active product status and standard DO-214AC packaging.

For enhanced performance with extended temperature range: SMAJ85CAE3/TR13 (Microchip Technology) offers increased peak pulse current (3.6A) and power rating (500W) while maintaining the same clamping voltage (137V) and operating temperature range (-65°C ~ 150°C) as the original part.

For higher clamping voltage applications: SMAJ85CE3/TR13 (Microchip Technology) provides 151V clamping voltage with 3.3A peak pulse current and 500W power rating, suitable for circuits requiring higher transient suppression.

For maximum performance: SMA6J85CA-TR (STMicroelectronics) delivers the highest peak pulse current (22.5A at 8/20µs) and power rating (600W) with extended operating temperature range (-55°C ~ 175°C), though with slightly higher clamping voltage (146V).

For cost-optimized procurement: SMAJ85CA (Meritek) is available in high inventory (37,100 pcs) with active product status and equivalent electrical performance to Group A substitutes.

Frequently Asked Questions (FAQ)

Q: Can SMAJ85C be replaced with any of these substitute parts?

A: Yes, all listed parts share the same 85V reverse standoff voltage, DO-214AC (SMA) package, and ROHS3 compliance. Selection depends on specific clamping voltage and current requirements for your application.

Q: What is the difference between Group A and Group B substitutes?

A: Group A parts (SMAJ85CA, SMAJ85CA-13-F, TV04A850JB-G) clamp at 137V, providing tighter voltage regulation. Group B parts (SMAJ85CE3/TR13, SMA6J85CA-TR) clamp at 146–151V, offering higher transient energy absorption capacity.

Q: Does the operating temperature range affect substitution?

A: The SMAJ85C operates from -65°C to 150°C. Most substitutes operate from -55°C to 150°C. SMAJ85CAE3/TR13 and SMAJ85CE3/TR13 maintain the -65°C lower limit. SMA6J85CA-TR extends to 175°C. Verify your application's temperature requirements before selection.

Q: Are all substitute parts in active production?

A: Yes. All substitute parts listed have active product status, ensuring long-term availability and supply chain stability compared to the obsolete SMAJ85C.

Q: What is the significance of peak pulse current differences?

A: Peak pulse current indicates the maximum transient current the diode can suppress. Higher values (3.3A–22.5A) provide greater protection margin for high-energy transient events. The original SMAJ85C specifies 2.9A; substitutes range from 2.9A to 22.5A depending on the part selected.

Q: Can I use SMA6J85CA-TR as a direct replacement?

A: SMA6J85CA-TR is mechanically and electrically compatible but features significantly higher peak pulse current (22.5A) and power rating (600W). It is suitable for applications requiring enhanced transient protection but may be oversized for circuits designed for the original 2.9A specification.

Q: Are there packaging differences between these parts?

A: All parts use DO-214AC (SMA) surface-mount packaging. Some are supplied in Tape & Reel (TR) format for automated assembly. Verify packaging format requirements with your procurement process.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message