GA1A4M bipolar transistor — Specifications & Equivalents

About the GA1A4M

The GA1A4M is an NPN bipolar transistor with a collector–emitter voltage (V_CEO) rating of 50 V, a continuous collector current (I_C) of 0.1 A and a DC current gain (h_FE) of minimum 35. It can dissipate up to 0.15 W and is rated to a junction temperature of 150 °C. It is supplied in the SC70 package.

At a glance

• Type: NPN bipolar transistor
• Max collector–emitter voltage (V_CEO): 50 V
• Max collector current (I_C): 0.1 A
• DC current gain (h_FE): minimum 35
• Power dissipation (P_D): 0.15 W
• Max junction temperature (T_J): 150 °C
• Package: SC70

Typical applications

Judging from its ratings the GA1A4M is generally applied in small-signal amplification and general-purpose switching.

The quoted current gain of minimum 35 determines the base drive needed: divide your target collector current by the minimum h_FE, not the typical figure, when sizing the base resistor.

Biasing and absolute maximum ratings

Absolute-maximum breakdown limits are V_CEO 50 V, V_CBO 60 V and V_EBO 10 V (magnitudes). The emitter–base rating is the easiest to overlook and is often only a few volts, so protect the junction against reverse drive.

Dissipation is capped at 0.15 W, and that figure assumes the datasheet's mounting and ambient conditions — derate it for your own thermal design.

Choosing a replacement for the GA1A4M

A drop-in substitute for the GA1A4M must be the same NPN type and offer a collector–emitter rating of at least 50 V, a collector current rating of at least 0.1 A and current gain in the same ballpark as minimum 35.

Mechanically, check the replacement against the SC70 footprint and confirm the pin order — parts sharing a package outline do not always share a pinout.

Where the application switches inductive loads or runs near the voltage limit, keep extra headroom rather than choosing a part that only just meets the original numbers.

Frequently asked questions

What is the GA1A4M?

The GA1A4M is an NPN bipolar junction transistor (BJT). It is rated for 50 V collector-emitter and 0.1 A continuous collector current.

What is the maximum voltage of the GA1A4M?

Maximum collector-emitter voltage (Vceo) is 50 V, and collector-base (Vcbo) is 60 V.

How much current can the GA1A4M handle?

Continuous collector current is rated at 0.1 A, with dissipation limited to 0.15 W.

What is the hFE of the GA1A4M?

DC current gain (hFE) is quoted as minimum 35. Size base drive from the minimum value so the transistor saturates fully across production spread.

What package does the GA1A4M come in?

It is listed in SC70. Verify the pinout of the specific variant, as one outline can carry different pin assignments.

What can I use to replace the GA1A4M?

This page lists 9 candidate equivalents matched on electrical ratings and package. Any replacement should meet or exceed the original voltage, current and dissipation figures and use a compatible drive level.