TIC126M-S SCR 600V 12A TO-220 Equivalent & Substitute Parts

Part Overview

The TIC126M-S is a silicon controlled rectifier (SCR) rated for 600V off-state voltage and 12A RMS on-state current in a TO-220-3 through-hole package. Manufactured by Bourns Inc., this component is classified as obsolete. Due to its discontinued status, equivalent substitute parts from active manufacturers are necessary for new designs and ongoing production requirements. Substitute SCRs must maintain electrical compatibility across voltage, current, and gate trigger specifications while accommodating the through-hole TO-220 package form factor.

Key Parameters

Parameter	TIC126M-S Value	Unit
Voltage - Off State	600	V
Voltage - Gate Trigger (Vgt) Max	1.5	V
Current - Gate Trigger (Igt) Max	20	mA
Voltage - On State (Vtm) Max	1.4	V
Current - On State (It RMS) Max	12	A
Current - Hold (Ih) Max	40	mA
Current - Off State Max	2	mA
Current - Non Rep. Surge (Itsm)	100	A @ 50Hz
SCR Type	Standard Recovery	—
Operating Temperature Range	-40 to 110	°C
Mounting Type	Through Hole	—
Package / Case	TO-220-3	—
RoHS Status	ROHS3 Compliant	—

Substitute Part Grouping Explanation

Substitution logic for the TIC126M-S is based on the following electrical and mechanical criteria:

Primary Substitution Criteria:

Off-state voltage rating: 600V minimum
On-state current (RMS): 12A or greater
Gate trigger voltage (Vgt): 1.5V or lower
Gate trigger current (Igt): 20mA or lower
Hold current (Ih): 40mA or lower
Package: TO-220-3 through-hole configuration
SCR type: Standard Recovery or Sensitive Gate (both acceptable for general switching applications)

Acceptable Parameter Variations:

On-state voltage (Vtm) may exceed 1.4V up to 2.2V without functional impact
Off-state leakage current may be lower than 2mA (improved performance)
Operating temperature range may extend beyond -40 to 110°C
Non-repetitive surge current (Itsm) may vary within manufacturer specifications

Substitute parts are grouped into two categories: direct current-rated equivalents (MCR12MG at 12A) and higher current-rated alternatives (TYN616RG at 16A, TYN625RG at 25A) suitable for applications with current margin requirements. Lower current-rated parts (MCR72-8G, MCR72-8TG, TYN608RG, TYN610RG at 8A and 10A respectively) are listed for reference but require circuit re-evaluation for current derating.

Parameter Comparison

Parameter	TIC126M-S	MCR12MG	MCR72-8G	MCR72-8TG	TYN608RG	TYN610RG	TYN616RG	TYN625RG	Unit
Voltage - Off State	600	600	600	600	600	600	600	600	V
Voltage - Gate Trigger (Vgt) Max	1.5	1	1.5	1.5	1.3	1.5	1.5	1.3	V
Current - Gate Trigger (Igt) Max	20	20	200	200	15	15	25	40	mA
Voltage - On State (Vtm) Max	1.4	2.2	2	2	1.6	1.6	1.6	1.6	V
Current - On State (It RMS) Max	12	12	8	8	8	10	16	25	A
Current - Hold (Ih) Max	40	40	6	6	30	30	40	50	mA
Current - Off State Max	2	10	10	10	5	10	5	5	µA
Current - Non Rep. Surge (Itsm)	100 @ 50Hz	100 @ 60Hz	100 @ 60Hz	100 @ 60Hz	95, 100	100, 105	160, 167	300, 314	A
SCR Type	Standard Recovery	Standard Recovery	Sensitive Gate	Sensitive Gate	Standard Recovery	Standard Recovery	Standard Recovery	Standard Recovery	—
Operating Temperature Range	-40 to 110	-40 to 125	-40 to 110	-40 to 110	-40 to 125	-40 to 125	-40 to 125	-40 to 125	°C
Package / Case	TO-220-3	TO-220-3	TO-220-3	TO-220-3	TO-220-3	TO-220-3	TO-220-3	TO-220-3	—
RoHS Status	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	ROHS3 Compliant	—

Engineering Selection Recommendations

Direct Equivalent (Recommended Primary Substitute): MCR12MG from Littelfuse Inc. provides the closest functional match with identical 12A RMS current rating and 600V off-state voltage. This part is active in production status and ROHS3 compliant. The lower gate trigger voltage (1V vs. 1.5V) and higher on-state voltage (2.2V vs. 1.4V) are within acceptable operating margins for standard switching applications. Packaging is TO-220AB, mechanically compatible with TO-220-3 footprints.

Higher Current Alternatives (For Current Margin Applications): TYN616RG (16A) and TYN625RG (25A) from STMicroelectronics are active production parts suitable for applications requiring additional current capacity. Both maintain 600V off-state voltage and are ROHS3 compliant with extended operating temperature ranges (-40 to 125°C). These parts provide design margin for thermal or transient current conditions.

Lower Current Alternatives (For Current Derating): MCR72-8G (Littelfuse) and MCR72-8TG (onsemi) are 8A-rated sensitive gate SCRs. These require circuit re-evaluation due to reduced current capacity. MCR72-8TG carries REACH Affected status, whereas MCR72-8G is REACH Unaffected. TYN608RG and TYN610RG from STMicroelectronics provide 8A and 10A ratings respectively with standard recovery characteristics and are suitable only for applications with confirmed lower current requirements.

Compliance Considerations: All substitute parts maintain ROHS3 compliance. MCR72-8TG is the only part with REACH Affected status. STMicroelectronics parts (TYN series) are uniformly REACH Unaffected. Littelfuse MCR12MG is REACH Unaffected, making it the preferred choice for applications with REACH compliance requirements.

Frequently Asked Questions (FAQ)

Q: Can MCR12MG directly replace TIC126M-S without circuit modification? A: MCR12MG is mechanically and electrically compatible for direct substitution in most applications. The lower gate trigger voltage (1V vs. 1.5V) improves gate sensitivity, and the higher on-state voltage (2.2V vs. 1.4V) results in slightly higher power dissipation. Verify thermal design margins in high-current or high-frequency switching scenarios.

Q: What is the difference between Standard Recovery and Sensitive Gate SCR types? A: Standard Recovery SCRs (TIC126M-S, MCR12MG, TYN series) require higher gate trigger current (15-25mA) for reliable triggering. Sensitive Gate SCRs (MCR72-8G, MCR72-8TG) require only 200µA gate trigger current, enabling lower-power gate drive circuits. Sensitive Gate types are not direct substitutes for Standard Recovery applications without gate drive circuit redesign.

Q: Are TO-220AB and TO-220-3 packages mechanically interchangeable? A: Yes. TO-220AB is a variant designation of the TO-220-3 package. Both feature three leads with identical pin spacing (2.54mm) and mounting hole patterns, allowing direct PCB footprint compatibility.

Q: Why are higher current-rated parts (TYN616RG, TYN625RG) listed as substitutes for a 12A part? A: Higher current ratings provide design margin for transient overcurrent conditions, thermal derating at elevated ambient temperatures, and future design revisions. These parts maintain identical voltage ratings and are pin-compatible, making them suitable for applications where current capacity margin is beneficial.

Q: What is the impact of MCR12MG's higher on-state voltage (2.2V vs. 1.4V)? A: Higher on-state voltage increases power dissipation in the SCR. For a 12A load, this represents approximately 0.8W additional dissipation. Verify that the thermal design (heatsink, PCB copper area) accommodates this increase. For low-current applications or pulse-mode operation, this difference is typically negligible.

Q: Can TYN610RG (10A) be used instead of TIC126M-S (12A)? A: TYN610RG is suitable only if the application circuit operates at or below 10A RMS current. This requires circuit re-evaluation and thermal analysis. The part is not a direct substitute for 12A-rated designs without current derating confirmation.

Q: What does REACH Affected status mean for MCR72-8TG? A: REACH Affected indicates the part may contain substances of concern under EU REACH regulations. For applications subject to REACH compliance requirements, select REACH Unaffected alternatives such as MCR72-8G or any STMicroelectronics TYN series part.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message