A1941 bipolar transistor — Specifications & Equivalents

About the A1941

The A1941 is a PNP bipolar transistor with a collector–emitter voltage (V_CEO) rating of 160 V, a continuous collector current (I_C) of 10 A and a DC current gain (h_FE) of minimum 55. It can dissipate up to 100 W and is rated to a junction temperature of 150 °C. It is supplied in the TO-3PN package.

At a glance

• Type: PNP bipolar transistor
• Max collector–emitter voltage (V_CEO): 160 V
• Max collector current (I_C): 10 A
• DC current gain (h_FE): minimum 55
• Transition frequency (f_T): 30 MHz
• Power dissipation (P_D): 100 W
• Max junction temperature (T_J): 150 °C
• Package: TO-3PN

Typical applications

Judging from its ratings the A1941 is generally applied in power output and driver stages.

A transition frequency (f_T) of 30 MHz indicates the frequency range over which useful current gain remains available.

The quoted current gain of minimum 55 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 160 V, V_CBO 160 V and V_EBO 5 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 100 W, and that figure assumes the datasheet's mounting and ambient conditions — derate it for your own thermal design.

Choosing a replacement for the A1941

A drop-in substitute for the A1941 must be the same PNP type and offer a collector–emitter rating of at least 160 V, a collector current rating of at least 10 A, current gain in the same ballpark as minimum 55 and a transition frequency of at least 30 MHz for the same bandwidth.

Mechanically, check the replacement against the TO-3PN 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 A1941?

The A1941 is a PNP bipolar junction transistor (BJT). It is rated for 160 V collector-emitter and 10 A continuous collector current.

What is the maximum voltage of the A1941?

Maximum collector-emitter voltage (Vceo) is 160 V, and collector-base (Vcbo) is 160 V.

How much current can the A1941 handle?

Continuous collector current is rated at 10 A, with dissipation limited to 100 W.

What is the hFE of the A1941?

DC current gain (hFE) is quoted as minimum 55. Size base drive from the minimum value so the transistor saturates fully across production spread.

What package does the A1941 come in?

It is listed in TO-3PN. Verify the pinout of the specific variant, as one outline can carry different pin assignments.

What can I use to replace the A1941?

This page lists 17 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.