## 2SA1774-R: General Purpose PNP Transistor The **2SA1774-R** is a high-frequency, small-signal PNP epitaxial planar silicon transistor. It is widely used in compact electronic devices for switching and amplification tasks. --- ### 1. Key Technical Specifications Below are the typical absolute maximum ratings and electrical characteristics for the "R" grade variant: | Parameter | Symbol | Rating | Unit | | :--- | :--- | :--- | :--- | | Collector-Base Voltage | $V_{CBO}$ | -60 | V | | Collector-Emitter Voltage | $V_{CEO}$ | -50 | V | | Emitter-Base Voltage | $V_{EBO}$ | -6 | V | | Collector Current | $I_C$ | -150 | mA | | Power Dissipation | $P_D$ | 150 | mW | | DC Current Gain ($h_{FE}$) | $h_{FE}$ | 180 to 390 | (R Class) | | Transition Frequency | $f_T$ | 140 | MHz | --- ### 2. Physical Packaging The 2SA1774 series is primarily found in the **SOT-416 (SC-75)** package. This is an ultra-small surface-mount device (SMD) package, making it ideal for high-density circuit boards. ### 3. Pin Configuration | Pin Number | Name | Function | | :--- | :--- | :--- | | 1 | **Base** | Controls the bias of the transistor | | 2 | **Emitter** | Outflow of current (PNP) | | 3 | **Collector** | Inflow of current (PNP) | --- ### 4. Features and Applications * **Small Package:** Saves significant PCB space in mobile phones and wearables. * **Low Noise:** Suitable for sensitive pre-amplification stages. * **Complementary Pair:** Its NPN counterpart is the **2SC4617**. #### Common Uses: 1. **General Purpose Switching:** Turning on/off small loads like LEDs or signal relays. 2. **Small Signal Amplification:** Used in audio and RF signal processing. 3. **Level Shifting:** Converting signal voltages between different circuit stages. --- ### 5. Part Number Suffix Breakdown (2SA1774-R) * **2S:** Standard Japanese semiconductor prefix. * **A:** PNP High Frequency type. * **1774:** Specific model number. * **-R:** Gain classification ($h_{FE}$ range). Usually, R represents a gain between 180 and 390. Other versions include "Q" (120-270) or "S" (270-560).