Overview
The LP395Z/NOPB is a fast monolithic transistor produced by Texas Instruments, designed with comprehensive protection features to enhance reliability and simplify protection circuitry. This device is part of the Ultra Reliable Power Transistor series and is known for its high gain and blowout-proof design. Although the LP395 has been discontinued by Texas Instruments, it remains a significant component in legacy systems and applications where its unique features are beneficial.
Key Specifications
| Parameter | Conditions | Typical | Maximum |
|---|---|---|---|
| Collector to Emitter Voltage (VCE) | 36 V | ||
| Collector to Base Voltage (VCB) | 36 V | ||
| Base to Emitter Voltage (VBE) (Forward) | 36 V | ||
| Base to Emitter Voltage (VBE) (Reverse) | 10 V | ||
| Base to Emitter Current (IBE) (Reverse) | 20 mA | ||
| Collector Current Limit | VBE = 2V, VCE = 36V | 45 mA | 25 mA (Min) |
| Quiescent Current (IQ) | VBE = 0V, 0 ≤ VCE ≤ 36V | 0.24 mA | 0.60 mA (Max) |
| Saturation Voltage (VCE(SAT)) | VBE = 2V, IC = 100 mA | 1.82 V | 2.10 V (Max) |
| Switching Time (tS) | VCE = 20V, RL = 200Ω | 2 μs | |
| Operating Temperature Range | −40°C to +125°C | ||
| Storage Temperature Range | −65°C to +150°C |
Key Features
- Internal Thermal Limiting: The device includes thermal overload protection at the chip level, preventing excessive die temperature.
- Internal Current and Power Limiting: The LP395 has built-in current and power limiting, making it difficult to destroy from most types of overload.
- High Gain and Blowout-Proof Design: Ideal for reliably driving small incandescent lamps and solenoids due to its low drive requirements and robust design.
- Specified 100 mA Output Current: Capable of delivering up to 100 mA of collector current.
- Low Quiescent Current: Typical quiescent current is 0.24 mA, with a maximum of 0.60 mA.
- Direct Interface with TTL or CMOS: Compatible with both TTL and CMOS logic levels.
- Base Voltage Tolerance: The base can be driven positive up to 36 volts without damage.
- Fast Switching Time: Switching time is typically 2 μs.
Applications
- Small Incandescent Lamp Drivers: The LP395 is particularly useful for driving small incandescent lamps due to its high gain and blowout-proof design, which helps in limiting cold filament inrush current and increasing lamp life.
- Solenoid Drivers: Suitable for driving solenoids with low drive requirements.
- Optically Isolated Switches: Can be used in optically isolated switch configurations.
- Two-Terminal Current Limiters: Can function as a two-terminal current limiter.
- Composite PNP Circuits: Can be used to create composite PNP transistor circuits.
Q & A
- What is the maximum collector to emitter voltage for the LP395?
The maximum collector to emitter voltage (VCE) is 36 volts.
- What is the specified output current of the LP395?
The specified output current is 100 mA.
- Does the LP395 have internal thermal protection?
Yes, the LP395 includes internal thermal overload protection at the chip level.
- What is the typical switching time of the LP395?
The typical switching time is 2 μs.
- Can the LP395 be used with TTL or CMOS logic?
Yes, the LP395 can directly interface with both TTL and CMOS logic levels.
- What is the operating temperature range of the LP395?
The operating temperature range is −40°C to +125°C.
- Why is the LP395 suitable for driving small incandescent lamps?
The LP395 is suitable due to its high gain, blowout-proof design, and current limiting characteristics, which help in limiting cold filament inrush current and increasing lamp life.
- Is the LP395 still in production?
No, the LP395 has been discontinued by Texas Instruments.
- What package type is the LP395 available in?
The LP395 is available in a TO-92 package.
- What are the key precautions when using the LP395?
Precautions include avoiding excessive collector to emitter voltage, using a series resistor in the base lead to prevent oscillations, and ensuring proper supply by-passing due to its high frequency response.
