2N5431 PN UNIJUNCTION TRANSISTOR High-reliability discrete products and engineering services since 1977 FEATURES Available as “HR” (high reliability) screened per MIL-PRF-19500, JANTX level. Add “HR” suffix to base part number. Available as non-RoHS (Sn/Pb plating), standard, and as RoHS by adding “-PBF” suffix. MAXIMUM RATINGS Rating Symbol Value Unit PD 360 mW Ie 50 mA RMS power dissipation (1) RMS emitter current Peak pulse emitter current (2) Ie 1.5 Amp Emitter reverse voltage VB2E 30 Volts Interbase voltage(3) VB2B1 35 Volts Operating junction temperature range TJ -65 to +125 °C Storage temperature range Tstg -65 to +200 °C 1. 2. 3. Derate 3 mW/°C increase in ambient temperature. Duty cycle ≤ 1%, PRR = 10 PPS. Based upon power dissipation at TA = 25°C. ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise specified) Characteristic Symbol Min Max Unit ŋ 0.72 0.80 - Interbase resistance (VB2B1 = 3V, IE = 0) RBB 6 8.5 kΩ Interbase resistance temperature coefficient (VB2B1 = 3V, IE = 0, TA = 0 to 100°C) αRBB 0.4 0.8 %/°C Emitter saturation voltage (2) (VB2B1 = 10V, IE = 50mA) VEB1(sat) - 3 Volts Modulated interbase current (VB2B1 = 10V, IE = 50mA) IB2(mod) 5 30 mA IEB2O - 10 nA Peak point emitter current (VB2B1 = 25V) (VB2B1 = 4V) IP - 0.4 4 µA Valley point current (2) (VB2B1 = 20V, RB2 = 100ohms) IV 2 - mA Base one peak pulse voltage (VBB = 4V) VOB1 1 - Volts Intrinsic standoff ratio (VB2B1 = 10V) (1) Emitter reverse current (VB2E = 30V, IB1 = 0) 1. 2. ŋ. Intrinsic standoff ratio is defined in terms of the peak point voltage, V P, by means of the equation: VP = ŋVB2B1 + VF, where VF is about 0.45V at 25°C @ IF = 10µA and decreases with temperature at about 2.5 mV/°C. Components R 1, C1 and the UJT form a relaxation oscillator, the remaining circuitry serves as a peak voltage detector. The forward drop of diode D1 compensates for VF. To use, the “cal” button is pushed, and R3 is adjusted to make the current meter, M1, read full scale. When the ”cal” button is released, the value of ŋ is read directly from the meter, if full scale on the meter reads 1. PW = 300µs, duty cycle ≤ 2% to avoid internal heating, which may result erroneous readings. Rev. 20121019 High-reliability discrete products and engineering services since 1977 2N5431 PN UNIJUNCTION TRANSISTOR MECHANICAL CHARACTERISTICS Case: TO-18 Marking: Body painted, alpha-numeric Pin out: See below Rev. 20121019 High-reliability discrete products and engineering services since 1977 2N5431 PN UNIJUNCTION TRANSISTOR Rev. 20121019