BC858A-AQ

Overview

The Diotec Semiconductor BC858A-AQ is an AEC-Q101 qualified PNP silicon epitaxial planar transistor designed for surface-mount applications. It operates within a collector-emitter voltage (VCEO) of -30 V and a collector-base voltage (VCBO) of -30 V, supporting a continuous DC collector current (IC) of -100 mA and peak currents up to 200 mA. The device features a maximum power dissipation (Ptot) of 250 mW at 25°C ambient temperature. The 'A' suffix designates a DC current gain (hFE) group ranging from 125 to 250 at IC = 2 mA. It utilizes the SOT-23 package with a junction-to-ambient thermal resistance of 417 K/W and supports a junction temperature range of -55°C to +150°C.

Feature Summary

• Automotive-grade reliability compliant with AEC-Q101 qualification standards
• Three distinct DC current gain groups for precise circuit matching
• Low saturation voltage characteristics optimized for switching efficiency
• RoHS compliant and conflict minerals free manufacturing

Applications

• Automotive signal processing circuits
• General-purpose switching applications
• Amplification stages in industrial control systems

Procurement Notes

Verify that the ordering code explicitly includes the '-AQ' suffix to confirm AEC-Q101 automotive qualification status. Ensure the component matches the specific 'A' gain bin requirements for your application's hFE tolerance. Confirm compliance with RoHS directives and REACH regulations during the sourcing process. Validate that the manufacturer documentation aligns with the requested specifications before finalizing procurement orders.

Selection Notes

Select this component when automotive reliability and high gain consistency are required. The BC858 variant provides lower voltage ratings compared to the BC856 or BC857 series; verify that the -30 V breakdown limits suit the target circuit topology. The 'A' gain bin offers moderate amplification suitable for standard logic interfacing. Consider the thermal resistance and power dissipation limits when designing heat management strategies for densely packed PCB layouts.

Part Context

This part belongs to the BC85x family of general-purpose PNP transistors manufactured by Diotec Semiconductor. It serves as the complementary counterpart to the NPN BC848 series. The BC858 sub-series specifically targets low-voltage applications requiring robust switching performance. The AEC-Q101 qualification distinguishes it from commercial grade variants, ensuring suitability for harsh automotive environments.

Replacement Considerations

Direct substitutes include other AEC-Q101 qualified PNP transistors with identical -30 V ratings and SOT-23 packaging. Verify that alternative components meet the same hFE gain bin specifications (125–250) to maintain circuit performance parity without redesigning bias networks.