FR604-T Equivalent & Substitute Parts

Part Overview

The FR604-T is a general-purpose rectifier diode rated for 400 V DC reverse voltage and 6 A average rectified current, manufactured by Diodes Incorporated in an R-6 axial through-hole package. This part is classified as obsolete, necessitating identification of equivalent and substitute components for ongoing applications and new designs. Substitute parts must maintain electrical compatibility across voltage, current, and thermal specifications while accommodating packaging and availability constraints.

Key Parameters

Parameter	Value	Unit
Voltage - DC Reverse (Vr) (Max)	400	V
Current - Average Rectified (Io)	6	A
Voltage - Forward (Vf) (Max) @ If	1.3 V @ 6 A	V
Speed Classification	Fast Recovery ≤ 500ns, > 200mA (Io)	—
Reverse Recovery Time (trr)	150	ns
Current - Reverse Leakage @ Vr	10	µA @ 400 V
Mounting Type	Through Hole	—
Package / Case	R-6, Axial	—
Operating Temperature - Junction	-65 to 175	°C
RoHS Status	ROHS3 Compliant	—

Substitute Part Grouping Explanation

Substitution of the FR604-T is determined by the following critical parameters:

Mandatory Electrical Compatibility:

Voltage - DC Reverse (Vr) (Max): 400 V minimum
Current - Average Rectified (Io): 6 A minimum
Mounting Type: Through Hole
Package / Case: R-6, Axial

Secondary Electrical Considerations:

Voltage - Forward (Vf) (Max) @ If: 1.3 V @ 6 A or lower
Reverse Recovery Time (trr): 150 ns or lower (fast recovery preferred)
Current - Reverse Leakage @ Vr: 10 µA @ 400 V or lower

Compliance & Availability:

RoHS Status: ROHS3 Compliant preferred
Product Status: Active or Not For New Designs acceptable; Obsolete not acceptable
Operating Temperature Range: -55°C to 150°C minimum

Substitute parts meeting these criteria are grouped by electrical performance tier and product status.

Parameter Comparison

Parameter	FR604-T (Main)	1N5551	6A4-TP	FR604GP-AP	FR604GP-TP	HER605GP-AP
Manufacturer	Diodes Incorporated	Microchip Technology	Micro Commercial Co	Micro Commercial Co	Micro Commercial Co	Micro Commercial Co
Voltage - DC Reverse (Vr) (Max)	400 V	400 V	400 V	400 V	400 V	400 V
Current - Average Rectified (Io)	6 A	3 A	6 A	6 A	6 A	6 A
Voltage - Forward (Vf) (Max) @ If	1.3 V @ 6 A	1.2 V @ 9 A	950 mV @ 6 A	1.3 V @ 6 A	1.3 V @ 6 A	1.3 V @ 6 A
Speed Classification	Fast Recovery ≤ 500ns	Standard Recovery >500ns	Standard Recovery >500ns	Fast Recovery ≤ 500ns	Fast Recovery ≤ 500ns	Fast Recovery ≤ 500ns
Reverse Recovery Time (trr)	150 ns	2 µs	—	150 ns	150 ns	50 ns
Current - Reverse Leakage @ Vr	10 µA @ 400 V	1 µA @ 400 V	10 µA @ 400 V	10 µA @ 400 V	10 µA @ 400 V	10 µA @ 400 V
Package / Case	R-6, Axial	B, Axial	R-6, Axial	R-6, Axial	R-6, Axial	R-6, Axial
Operating Temperature - Junction	-65 to 175°C	-65 to 175°C	-55 to 125°C	-55 to 150°C	-55 to 150°C	-55 to 150°C
Product Status	Obsolete	Active	Not For New Designs	Active	Active	Active
RoHS Status	ROHS3 Compliant	RoHS non-compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant

Engineering Selection Recommendations

Primary Substitutes (Recommended for New Designs):

FR604GP-AP and FR604GP-TP are the preferred substitutes for the obsolete FR604-T. Both parts are manufactured by Micro Commercial Co and maintain identical electrical specifications to the original part: 400 V reverse voltage, 6 A average rectified current, 1.3 V forward voltage at 6 A, and 150 ns reverse recovery time. Both are ROHS3 compliant and carry Active product status. The FR604GP-TP variant is supplied in Tape & Reel packaging, while FR604GP-AP is supplied in bulk. Operating temperature range is -55°C to 150°C, which is narrower than the original FR604-T (-65°C to 175°C) but suitable for most applications.

HER605GP-AP is an alternative substitute with superior fast recovery characteristics (50 ns reverse recovery time versus 150 ns). This part maintains all other electrical specifications identical to FR604-T and is ROHS3 compliant with Active product status. The faster recovery time may provide performance benefits in high-frequency switching applications.

Secondary Substitutes (Limited Application):

6A4-TP is classified as Not For New Designs but remains electrically compatible with the FR604-T in terms of voltage and current ratings. This part features a lower forward voltage (950 mV @ 6 A) compared to the original specification (1.3 V @ 6 A), which may reduce power dissipation in some applications. However, the operating temperature range (-55°C to 125°C) is more restricted than the original part. ROHS3 compliance is maintained.

Not Recommended:

1N5551 is not suitable as a direct substitute due to reduced current rating (3 A versus 6 A required). Although it maintains 400 V reverse voltage and is available in Active status, the current limitation makes it incompatible with applications requiring 6 A operation. Additionally, 1N5551 is RoHS non-compliant and exhibits standard recovery characteristics (2 µs) rather than fast recovery.

Frequently Asked Questions (FAQ)

Q: Can the 1N5551 be used as a substitute for the FR604-T?

A: No. The 1N5551 is rated for 3 A average rectified current, while the FR604-T requires 6 A operation. Using an undersized component will result in thermal stress and potential failure. Additionally, 1N5551 is RoHS non-compliant.

Q: What is the difference between FR604GP-AP and FR604GP-TP?

A: Both parts are electrically identical and manufactured by Micro Commercial Co with identical specifications. The primary difference is packaging: FR604GP-AP is supplied in bulk, while FR604GP-TP is supplied in Tape & Reel format. Selection depends on assembly process requirements and volume considerations.

Q: Why is HER605GP-AP recommended as an alternative?

A: HER605GP-AP maintains all critical electrical specifications of the FR604-T (400 V, 6 A, 1.3 V forward voltage) while offering superior fast recovery performance with a 50 ns reverse recovery time compared to 150 ns in the original part. This faster recovery reduces switching losses in high-frequency applications. It is ROHS3 compliant and carries Active product status.

Q: Is the 6A4-TP suitable for new designs?

A: The 6A4-TP is classified as Not For New Designs by the manufacturer. While it meets the voltage and current requirements, this designation indicates the manufacturer does not recommend it for new applications. For new designs, FR604GP-AP, FR604GP-TP, or HER605GP-AP are preferred.

Q: What is the impact of the narrower operating temperature range in substitute parts?

A: The substitute parts (FR604GP-AP, FR604GP-TP, HER605GP-AP) operate from -55°C to 150°C, compared to the original FR604-T range of -65°C to 175°C. For most commercial and industrial applications operating within -40°C to 125°C, this difference is not significant. Applications requiring operation below -55°C or above 150°C must retain the original FR604-T or identify alternative solutions.

Q: Are all recommended substitutes RoHS3 compliant?

A: Yes. FR604GP-AP, FR604GP-TP, HER605GP-AP, and 6A4-TP are all ROHS3 compliant. The 1N5551 is RoHS non-compliant and should not be used in applications requiring RoHS compliance.

Q: Can the R-6 axial package be interchanged with other package types?

A: No. The R-6 axial package is specific to through-hole assembly. The 1N5551, which uses a B axial package, has different physical dimensions and cannot be directly substituted in PCB layouts designed for R-6 packages. Package compatibility must be verified during component selection.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message