The C945 is an NPN planar silicon epitaxial transistor designed for audio amplifier and low speed switching applications.
Characteristics of C945 Transistor
Type: NPN
Collector-Emitter Voltage, max: 50 V
Collector-Base Voltage, max: 60 V
Emitter-Base Voltage, max: 5 V
Collector Current − Continuous, max: 0.15 A
Collector Dissipation: 0.4 W
DC Current Gain (hfe): 70 to 700
Transition Frequency, min: 150 MHz
Operating and Storage Junction Temperature Range: -55 to +150 °C
Package: TO-92
Pinout of C945
The C945 is manufactured in a plastic TO-92 case. When looking at the flat side with the leads pointed downward, the three leads emerging from the transistor are, from left to right, the emitter, collector, and base leads. Here is an image showing the pin diagram of this transistor.
Classification of hFE
The C945 transistor can have a current gain of 70 to 700. The gain of the C945BL will be in the range from 350 to 700, for the C945GR it will be in the range from 200 to 400, for the C945O it will be in the range from 70 to 140, for the C945Y it will be in the range from 120 to 240.
Complementary PNP transistor
The complementary PNP transistor to the C945 is the A733.
SMD Version of C945 transistor
The 2SC2712 (SOT-23), 2SC4116 (SOT-323), 2SC4738 (SOT-23), FJX945 (SOT-323), KTC3875 (SOT-23) and KTC3875S (SOT-23) is the SMD version of the C945 transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.
Replacement and Equivalent for C945 transistor
The main parameters to pay attention to when choosing a replacement for the C945 transistor:
Type (NPN)
Collector-Emitter breakdown voltage (equal or higher than 50 V)
Maximum Collector current (equal or higher that 0.15 A)
DC current gain (equal or higher that 70, but not too high)
Package (TO-92)
Pinout (some transistors may have similar characteristics to the C945, but differ in pinout)
