Unijunction Transistor Description: A PN unijunction transistor in a TO-92 type package designed for use in pulse and timing circuits, sensing circuits and thyristor trigger circuits Absolute maximum Ratings: (Ta = +25C unless otherwise specified) Power Dissipation, Pd Derate Above 25C RMS Emitter Current, Ie(rms) Peak Pulse Emitter Current (Note 1) Current, ie Emitter Reverse Voltage, Vb2e Interbase Voltage, Vb2b1 Operating Junction Temperature Range, Tj Storage Temperature Range, Tstg : 300mW : 3.0mW/C : 50mA : 1.5A : 30V : 35V : -65C to +125C : -65C to +150C Electrical Characteristics: (Ta = +25C Unless otherwise specified) Parameter Symbol Instrinsic Standoff Ratio Interbase Resistance Test Conditions Min Typ Max Unit Vb2b1 = 10V, Note3 0.70 - 0.85 - 4.0 6.0 9.1 k 0.1 - 0.9 %/C rbb Interbase Resistance Temperature Coefficient Emitter Saturation Voltage Veb1(sat) Vb2b1 = 10V, Ie = 50mA, Note 4 - 2.5 - V Modulated interbase Current Ib2(mod) Vb2b1 = 10V, Ie = 50mA - 15 - mA Emitter Reverse Current Ieb20 Vb2e = 30V, Ib1 = 0 - 0.005 1 A Peak Point Emitter Current Ip Vb2b1 = 25V - 1 5 A Valley Point Current Iv Vb2b1 = 20V, Rb2 = 100, Note 4 4 7 - mA Base-One Peak Pulse Voltage VOb1 5 8 - V Notes: 1. Duty Cycle < = 1% PRR = 10PPS. 2. Based upon power dissipation at Ta = +25C 3. Intrinsic standoff ratio is essentially constant with temperature and interbase voltage and is defined by the equation: Vp - Vbb + Vd W here: Vp = Peak Point Emitter Voltage; Vbb = interbase Voltage; Vd = Junction Diode Drop (~0.5V). 4. Use Pulse techniques: Pulse width ~ 300S, Duty Cycle < = 2% to avoid internal heating due to interbase modulation which may result in erroneous readings. www.element14.com www.farnell.com www.newark.com Page <1> 10/09/12 V1.0 Unijunction Transistor Dim Min Max A 4.32 5.33 B 4.45 5.2 C 3.18 4.19 D 0.41 0.55 E 0.35 F 0.5 5 G 1.14 1.4 H 1.14 1.53 K 12.7 Dimensions : Millimetres Part Number Table Description Part Number Unijunction Transistor, TO-92, PN 2N4871 Important Notice : This data sheet and its contents (the "Information") belong to the members of the Premier Farnell group of companies (the "Group") or are licensed to it. No licence is granted for the use of it other than for information purposes in connection with the products to which it relates. No licence of any intellectual property rights is granted. The Information is subject to change without notice and replaces all data sheets previously supplied. The Information supplied is believed to be accurate but the Group assumes no responsibility for its accuracy or completeness, any error in or omission from it or for any use made of it. Users of this data sheet should check for themselves the Information and the suitability of the products for their purpose and not make any assumptions based on information included or omitted. Liability for loss or damage resulting from any reliance on the Information or use of it (including liability resulting from negligence or where the Group was aware of the possibility of such loss or damage arising) is excluded. This will not operate to limit or restrict the Group's liability for death or personal injury resulting from its negligence. Multicomp is the registered trademark of the Group. (c) Premier Farnell plc 2012. www.element14.com www.farnell.com www.newark.com Page <2> 10/09/12 V1.0