2SA684 Bipolar Transistor

• Type: PNP
• Collector-Emitter Voltage, max: -50 V
• Collector-Base Voltage, max: -60 V
• Emitter-Base Voltage, max: -5 V
• Collector Current − Continuous, max: -1 A
• Collector Dissipation: 1 W
• DC Current Gain (h_fe): 85 to 340
• Transition Frequency, min: 200 MHz
• Operating and Storage Junction Temperature Range: -55 to +150 °C
• Package: TO-92MOD

Here is an image showing the pin diagram of this transistor.The 2SA684 transistor can have a current gain of 85 to 340. The gain of the 2SA684-Q will be in the range from 85 to 170, for the 2SA684-R it will be in the range from 120 to 240, for the 2SA684-S it will be in the range from 170 to 340.Sometimes the "2S" prefix is not marked on the package - the 2SA684 might only be marked "A684".The complementary NPN transistor to the 2SA684 is the 2SC1384.The 2SB710A (SOT-23), 2SB766A (SOT-89), FMMTA55 (SOT-23), KST55 (SOT-23) and MMBT4354 (SOT-23) is the SMD version of the 2SA684 transistor. These transistors are of the same type, have similar parameters and are designed for surface mounting.You can replace the 2SA684 with the 2SA1534A.