2SD400 is an NPN transistor available in TO-92LM or TO-92MOD package. This transistor is mainly designed to use in electronics low-frequency amplifiers and also in electronics governor circuits. An electronic governor is a circuit that controls the speed of a machine. Other than these uses this transistor can also be used in a variety of other general-purpose applications. The maximum collector current of the transistor is 1A due to which it can be used to drive a variety of loads in a circuit that falls under 1A when used as a switch. The max collector to emitter saturation voltage of the transistor is only 0.3V and typically only 0.1V. To drive 500mA of load the base current should be 50mA and to drive load of 1A the base current should be 100mA.

Additionally, it can also be used as a general-purpose audio amplifier, and also in RF circuits, the max transition frequency of the transistor is up to 180MHz due to which it can also be used in RF circuits under 180MHz.

Moreover, the max collector dissipation of the transistor is 900mA and the minimum and maximum DC current gain is 60 to 560 however the transistor is available in four different categories according to the DC current gain which can be determined by the first letter written below the part number. If that letter is “D” then the gain will be 60 to 120, if the letter is “E” then the gain will be 100 to 200, if it is “F” then the gain will be 160 to 320, and if “G” then the gain will be 280 to 560.

Features / Technical Specifications:

• Package Type: TO-92LM / TO-92MOD
• Transistor Type:  NPN
• Max Collector Current(I_C): 1A
• Max Collector-Emitter Voltage (V_CE): 25V
• Max Collector-Base Voltage (V_CB): 25V
• Max Emitter-Base Voltage (VEBO): 5V
• Max Collector Dissipation (Pc): 900mW
• Max Transition Frequency (fT): 180 MHz
• Minimum & Maximum DC Current Gain (h_FE) 60– 560
• Max Storage & Operating temperature Should Be: -55 to +150 Centigrade

Replacement and Equivalent

2SD2206, 2SC3207, 2SC3070, 2SD1930, 2SD400MP, 2SD400P-1, 2SC4781, CE2F3P, 2SD1140, 2SD2213, KTD2854, NTE2341, STX112, 2SC4682, ZTX690B, 2SC3225, ZTX692B, 2SC3726, 2SD1153, 2SD1929, 2SD1984, 2SD2088, 2SD2206A.

Where We Can Use it & How to Use

As said above D400 transistor is mainly designed for low-frequency amps and electronic governor applications but it is not limited to that and can also be used for a wide variety of other general-purpose applications. For example, it can be used in variety of switching applications, audio amplifier applications, and also in radio and RF applications under 180 MHz frequencies.

Applications

• Low frequency amps
• Speed control circuits
• Audio Amplifiers
• Switching loads under 1A
• Radio frequency circuits

How to Safely Long Run in a Circuit

To get long term performance with D400 transistor it is suggested to always use it 20% below from its max ratings. The maximum collector current of the transistor is 1A therefore do not drive load of more than 800mA. The max collector to emitter voltage is 25V therefore do not drive load of more than 20V and always store and operate the transistor in temperature above -55 degree centigrade and below +150 centigrade.

Package Include:

1 x D400 Low-Frequency Power NPN Transistor