2N4851

Overview

The Central Semiconductor Corp 2N4851 is a PN silicon unijunction transistor housed in a TO-18 metal can package. It features an emitter reverse voltage of 30 V and an interbase voltage of 35 V. The device supports a peak emitter current of 1.5 A with a duty cycle not exceeding 1% and a pulse repetition rate of 10 pps. RMS power dissipation is rated at 300 mW, with an operating junction temperature range from -65 to +125 °C. The intrinsic standoff ratio ranges from 0.56 to 0.75 when the interbase voltage is 10 V.

Feature Summary

• Designed for timing, sensing, and trigger circuits
• Utilizes a robust TO-18 metal case construction
• Capable of handling high peak emitter currents

Applications

• Timing circuits
• Sensing applications
• Trigger circuits

Procurement Notes

This component has been officially discontinued by the manufacturer and is classified as End of Life. Current availability is restricted to existing stock only, with no further production orders accepted. Buyers must verify immediate inventory status through authorized distributors or direct sales representatives before placing orders. Last purchase dates are subject to six-month notice periods, and final shipments may be limited to twelve months from the discontinuation notice date.

Selection Notes

Engineers should note that this part is obsolete and no longer manufactured. Selection requires confirming available stock levels rather than standard ordering processes. Designers planning new hardware should evaluate alternative components immediately, as supply continuity cannot be guaranteed. Verify specific electrical parameters against legacy system requirements before committing to remaining inventory purchases.

Part Context

The 2N4851 belongs to a family of PN silicon unijunction transistors produced by Central Semiconductor Corp, alongside models 2N4852 and 2N4853. These devices share similar mechanical outlines and general functional purposes but differ in intrinsic standoff ratios and leakage characteristics. This specific model represents a legacy discrete semiconductor component previously used in analog control and oscillator designs.

Replacement Considerations

No official replacement part numbers are provided by the manufacturer for this discontinued item. Customers are advised to contact engineering support for assistance in locating alternate sources or suitable substitutes from other manufacturers.