BC490A

Single Bipolar Transistors Overview

The onsemi BC490A is a PNP silicon epitaxial planar transistor housed in a TO-92 (CASE 29) package. It features a maximum collector-emitter voltage of -80 Vdc and a continuous collector current rating of -1.0 Adc. The device offers a minimum DC current gain of 60 at -100 mAdc, with a typical current-gain bandwidth product of 150 MHz. Thermal characteristics include a junction-to-ambient resistance of 200 °C/W and a total power dissipation of 625 mW at 25°C ambient temperature.

Single Bipolar Transistors Feature Summary

• High-voltage capability with -80 V collector-emitter breakdown for robust switching applications
• High-current handling up to -1.0 A continuous collector current
• Fast dynamic performance with a typical 150 MHz gain-bandwidth product
• Lead-free packaging available compliant with environmental standards

Single Bipolar Transistors Applications

• General-purpose high-current switching circuits
• Linear amplifier stages requiring high voltage tolerance
• Driver circuits for loads demanding significant current transfer
• Complementary pairing with NPN transistors in push-pull configurations

Single Bipolar Transistors Procurement Notes

Verify the specific ordering suffix against the manufacturer's datasheet to confirm package style and shipping quantity. Standard bulk boxes contain 5000 units, while ammo box variants hold 2000 units. Ensure the selected part number matches the required lead-free designation if environmental compliance is mandatory for the assembly process.

Single Bipolar Transistors Selection Notes

Select the BC490A when circuit requirements exceed standard low-power transistor limits but do not necessitate a larger power package. Its -80 V rating provides headroom above common -40 V or -50 V alternatives. Verify that the thermal management strategy accommodates the 200 °C/W junction-to-ambient resistance for reliable operation under continuous load conditions.

Single Bipolar Transistors Part Context

This component belongs to the BC490 series of high-current PNP transistors manufactured by onsemi. It serves as the higher-gain variant within the family, distinguished from the standard BC490 by its minimum hFE specification of 60 compared to 40. The device utilizes planar epitaxial technology optimized for stable performance across the specified industrial temperature range.

Single Bipolar Transistors Replacement Considerations

Direct functional substitutes include the BC490, which shares identical electrical ratings but offers a lower minimum DC current gain of 40. Designers must verify that the reduced gain of the BC490 meets the base drive requirements of the specific application before swapping components.

Single Bipolar Transistors FAQ

What is the difference between the BC490 and BC490A?

The primary distinction lies in the DC current gain (hFE). The BC490A guarantees a minimum hFE of 60 at -100 mAdc, whereas the standard BC490 has a lower minimum hFE of 40 under the same conditions.

What is the maximum power dissipation at ambient temperature?

At an ambient temperature of 25°C, the total device dissipation is rated at 625 mW. This value decreases linearly at a derating factor of 5.0 mW/°C as the ambient temperature rises above 25°C.

How is the pinout configured for the TO-92 package?

Viewing the flat side of the TO-92 package with leads pointing down, Pin 1 is the Collector, Pin 2 is the Base, and Pin 3 is the Emitter.