1. General Information:

️· Type: PNP Bipolar Junction Transistor (BJT)
️· Manufacturer: Leshan Radio Company (implied by the "Leshan Radio Company" branding)
️· Application: Suitable for low-noise amplifier applications (explicitly mentioned).
️· Datasheet ID: Implied: This is an excerpt from a larger datasheet.

2. Electrical Characteristics:

️· Polarity: PNP
️· Key Parameters (From datasheet excerpts):
- Noise Figure: The datasheet emphasizes low noise characteristics, with figures and contours provided (see "Noise Characteristics" section below).
- Thermal Response: Design note explains how to use Figure 14 (Thermal Response) to calculate junction temperature rise under pulsed power conditions.

3. Noise Characteristics:

️· Noise Voltage (e_n): The noise voltage of the transistor. Referenced in Figure 3.
️· Noise Current (i_n): The noise current of the transistor. Referenced in Figure 4.
️· Source Resistance (R_s): The resistance of the source. Used in the noise figure calculation.
️· Noise Figure (NF): The crucial parameter for amplifiers. The formula for calculation is given:
```
NF = 20 log10 ( –––––––––––––––)
(e n [2] + 4KTR S + I n2 R S2)
```
Where:
- `K` is Boltzmann's Constant (1.38 x 10^-23 j/°K)
- `T` is the temperature of the Source Resistance (°K)
- Figures 3, 3 and 5 graphically illustrate noise characteristics and noise figure contours vs. collector current.

4. Dynamic Characteristics:

️· Turn-On Time: Illustrated in Figure 10.
️· Turn-Off Time: Illustrated in Figure 11.
️· Current-Gain - Bandwidth Product (h_FE·f_T): Illustrated in Figure 12.
️· Reverse Voltage: Illustrated in Figure 13.
️· Capacitance: Illustrated in Figure 13.
️· Thermal Response: Figure 14 shows thermal response curves.

5. Design Note & Thermal Considerations:

️· Transient Thermal Resistance (Z θJA(t)): A key design parameter. Calculated as the value from Figure 14 multiplied by the steady-state thermal resistance (R θJA).
️· Example Calculation: Shows how to calculate the peak junction temperature rise (∆T) for a specific pulsed power scenario (2.0W, t1=1.0ms, t2=5.0ms, D=0.2) resulting in a ∆T of 88°C.
️· Reference: Design note references document "AN-569" for more details.

6. Figures and Their Content:

️· Figure 1: Noise Voltage (vs. frequency)
️· Figure 2: Noise Current (vs. frequency)
️· Figure 3: Noise Voltage (vs. Collector Current)
️· Figure 4: Noise Current (vs. Collector Current)
️· Figure 5: Noise Figure Contours (vs. Collector Current)
️· Figure 6: Collector Saturation Region (graph)
️· Figure 7: Collector Characteristics (graph)
️· Figure 10: Turn-On Time (graph)
️· Figure 11: Turn-Off Time (graph)
️· Figure 12: Current-Gain – Bandwidth Product (graph)
️· Figure 13: Capacitance and Reverse Voltage (graph)
️· Figure 14: Thermal Response (graph)
️· Figure 15: Typical Collector Leakage Current (graph)