BCX70G Equivalent & Substitute Parts

Part Overview

The BCX70G is an NPN bipolar junction transistor manufactured by onsemi, housed in a SOT-23-3 surface mount package. This device is rated for 45 V collector-emitter breakdown voltage and 200 mA maximum collector current, with a maximum power dissipation of 350 mW. The BCX70G is classified as obsolete, necessitating identification of active substitute components for new designs and ongoing production requirements. Substitute parts must maintain electrical compatibility within the specified parameter ranges while offering active product status and current availability.

Key Parameters

Parameter	BCX70G Value	Unit
Transistor Type	NPN	—
Voltage - Collector Emitter Breakdown (Max)	45	V
Current - Collector (Ic) (Max)	200	mA
Power - Max	350	mW
Frequency - Transition	125	MHz
DC Current Gain (hFE) (Min) @ Ic, Vce	120 @ 2mA, 5V	—
Vce Saturation (Max) @ Ib, Ic	550mV @ 1.25mA, 50mA	—
Current - Collector Cutoff (Max)	20	nA
Package / Case	SOT-23-3	—
Mounting Type	Surface Mount	—
Moisture Sensitivity Level (MSL)	1 (Unlimited)	—

Substitute Part Grouping Explanation

Substitute parts for the BCX70G are selected based on strict electrical and mechanical compatibility criteria. The primary substitution logic is as follows:

Critical Parameters for Substitution:

Transistor Type: NPN (must match)
Package / Case: SOT-23-3 (must match for mechanical compatibility)
Voltage - Collector Emitter Breakdown (Max): 45 V (must equal or exceed)
Current - Collector (Ic) (Max): Must equal or exceed 200 mA
Power - Max: Must equal or exceed 350 mW
Mounting Type: Surface Mount (must match)

Substitution Categories:

Category A: Direct Current Capability Substitutes Parts with Ic (Max) ≥ 500 mA and all other parameters meeting or exceeding BCX70G specifications. These include BC817 variants (BC817-16LT1G, BC817-16LT3G, BC817-25LT1G, BC817-25LT3G, BC817-40LT1G, BC817-40LT3G). These parts provide enhanced current handling while maintaining voltage and package compatibility.

Category B: Lower Current Substitutes Parts with Ic (Max) = 100 mA, suitable only for applications where collector current does not exceed 100 mA. These include BC847 variants (BC847ALT1G, BC847BLT1G, BC847BLT3G, BC847CLT1G). These parts are not direct substitutes for full-current BCX70G applications but are compatible for reduced-current designs.

All substitute parts are active products with RoHS3 compliance and REACH unaffected status, providing long-term availability and regulatory compliance advantages over the obsolete BCX70G.

Parameter Comparison

Part Number	Manufacturer	Product Status	Ic (Max) mA	Vce Breakdown (Max) V	Power (Max) mW	Frequency - Transition MHz	hFE (Min) @ Ic, Vce	Package	RoHS Status
BCX70G	onsemi	Obsolete	200	45	350	125	120 @ 2mA, 5V	SOT-23-3	—
BC817-16LT1G	onsemi	Active	500	45	300	100	100 @ 100mA, 1V	SOT-23-3	ROHS3 Compliant
BC817-16LT3G	onsemi	Active	500	45	300	100	100 @ 100mA, 1V	SOT-23-3	ROHS3 Compliant
BC817-25LT1G	onsemi	Active	500	45	300	100	160 @ 100mA, 1V	SOT-23-3	ROHS3 Compliant
BC817-25LT3G	onsemi	Active	500	45	300	100	160 @ 100mA, 1V	SOT-23-3	ROHS3 Compliant
BC817-40LT1G	onsemi	Active	500	45	300	100	250 @ 100mA, 1V	SOT-23-3	ROHS3 Compliant
BC817-40LT3G	onsemi	Active	500	45	300	100	250 @ 100mA, 1V	SOT-23-3	ROHS3 Compliant
BC847ALT1G	onsemi	Active	100	45	300	100	110 @ 2mA, 5V	SOT-23-3	ROHS3 Compliant
BC847BLT1G	onsemi	Active	100	45	300	100	200 @ 2mA, 5V	SOT-23-3	ROHS3 Compliant
BC847BLT3G	onsemi	Active	100	45	300	100	200 @ 2mA, 5V	SOT-23-3	ROHS3 Compliant
BC847CLT1G	onsemi	Active	100	45	300	100	420 @ 2mA, 5V	SOT-23-3	ROHS3 Compliant

Engineering Selection Recommendations

For Applications Requiring Full 200 mA Collector Current:

The BC817 series (BC817-16LT1G, BC817-16LT3G, BC817-25LT1G, BC817-25LT3G, BC817-40LT1G, BC817-40LT3G) are the primary substitutes for BCX70G. All BC817 variants maintain the 45 V collector-emitter breakdown voltage and SOT-23-3 package compatibility. The BC817 series offers 500 mA maximum collector current, exceeding the BCX70G specification of 200 mA. All BC817 variants are active products with RoHS3 compliance, ensuring regulatory compliance and long-term supply availability.

Selection among BC817 variants depends on DC current gain (hFE) requirements:

BC817-16 variants: hFE (Min) = 100 @ 100mA, 1V
BC817-25 variants: hFE (Min) = 160 @ 100mA, 1V
BC817-40 variants: hFE (Min) = 250 @ 100mA, 1V

Packaging variants (LT1G vs. LT3G) differ in tape and reel configuration; electrical specifications are identical.

For Applications Limited to 100 mA Collector Current:

The BC847 series (BC847ALT1G, BC847BLT1G, BC847BLT3G, BC847CLT1G) are suitable substitutes only when circuit design limits collector current to 100 mA or less. These parts maintain 45 V collector-emitter breakdown voltage and SOT-23-3 package compatibility. BC847 variants offer varying DC current gain specifications and are all active products with RoHS3 compliance.

Compliance and Availability:

All substitute parts listed are active products manufactured by onsemi with RoHS3 compliance and REACH unaffected status. The BCX70G obsolete status necessitates transition to active alternatives for new designs and production continuity.

Frequently Asked Questions (FAQ)

Q: Can BC817 series parts directly replace BCX70G in all applications?

A: BC817 series parts are direct electrical and mechanical substitutes for BCX70G when collector current requirements do not exceed 500 mA. All BC817 variants maintain identical 45 V collector-emitter breakdown voltage and SOT-23-3 package specifications. The higher current rating of BC817 (500 mA vs. 200 mA) provides design margin without requiring circuit modification.

Q: What is the difference between BC817-16, BC817-25, and BC817-40 variants?

A: The numeric suffix indicates the minimum DC current gain (hFE) specification. BC817-16 specifies hFE (Min) = 100, BC817-25 specifies hFE (Min) = 160, and BC817-40 specifies hFE (Min) = 250, all measured at 100 mA collector current and 1 V collector-emitter voltage. Selection depends on circuit bias network design and required gain characteristics.

Q: What is the difference between LT1G and LT3G packaging designations?

A: LT1G indicates Cut Tape (CT) & Digi-Reel packaging, while LT3G indicates Tape & Reel (TR) packaging. Electrical specifications are identical; packaging designation reflects supply format and reel configuration for automated assembly processes.

Q: Can BC847 series parts replace BCX70G in high-current applications?

A: BC847 series parts are not suitable for applications requiring collector current above 100 mA. The BC847 maximum collector current rating is 100 mA, compared to BCX70G specification of 200 mA. BC817 series parts are required for applications utilizing the full 200 mA current capability of BCX70G.

Q: Are all substitute parts RoHS compliant?

A: All substitute parts listed (BC817 and BC847 series) are RoHS3 compliant. The BCX70G does not specify RoHS status. RoHS3 compliance ensures regulatory compliance with current environmental and hazardous substance restrictions.

Q: What is the operating temperature range for substitute parts?

A: BC817 series parts specify operating temperature range of -65°C to 150°C (TJ). BC847 series parts specify operating temperature range of -55°C to 150°C (TJ). Both ranges exceed typical industrial and commercial application requirements.

Q: Are substitute parts available in the same SOT-23-3 package?

A: All substitute parts are housed in SOT-23-3 (TO-236-3, SC-59) surface mount packages, identical to BCX70G. No PCB layout modification is required for mechanical compatibility.

Q: What is the moisture sensitivity level (MSL) for substitute parts?

A: All substitute parts specify MSL 1 (Unlimited), indicating no moisture sensitivity restrictions. Storage and handling requirements are identical to BCX70G.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message