COMSET SEMICONDUCT ORS 1/2
2N2646
2N2647
SILICON UNIJONCTION TRANSISTORS
Silicon Planar Unijunction Transistors have a structure resulting in lower saturation voltage, peak-point
current and valley current as well as a much higher base-one peak pulse voltage. In addition, these
devices are much faster switches.
The 2N2646 is intended for general purpose industrial applications where circuit economy is of primary
importance, and is ideal for use in firing circuits for Silicon Controlled Rectifiers and other applications
where a guarant eed m inimum puls e amplitude is req uir e d. The 2N264 7 is int ended for ap pl icati ons wher e
a low em itter leak age current and a low peak poi nt emitter cur rent (trigger c urrent) ar e requir ed and also
for triggering high power SCR’s.
MAXIMUM RATINGS (*)
TJ=125°C unless otherwise noted
Symbol Ratings 2N2646 2N2647
VB1E Base 1 – Emitter Voltage 30 V
VB2E Base 2 – Emitter Voltage 30 V
IFRMS RMS Emitter Current 50 mA
IEM Emitter Peak Current 2 A
PTOT Total Power Dissipation 300 mW
TJ Maximum Junction 150
TSTG Storage Temperature Range -55 to +175 °C
EL ECTRICAL CHARACTERISTICS
TJ=25°C unless otherwise noted, RGK=1000
2N2646 – 2N2647
Symbol Ratings Min Max
IEO Emitter Reverse Current 12 µA
V(BR)B1E Base 1 – Emitter Breakdown Voltage
IE =100 µA30 V
CASE
COMSET SEMICONDUCT ORS 2/2
2N2646
2N2647
2N2646 – 2N2647
Symbol Ratings Min Max
RBBO Interbase Resistance
VB1B2 = 3 V 4.7 9.1 k
2N2646 0.56 0.75
η
ηη
ηIntrinsic stand-off ratio
VB1B2 = 10 V 2N2647 0.68 0.82 -
VE(SAT) Emitter Saturation Voltage
IE = 50 mA, VB1B2 = 10 V -2.5V
2N2646 4-
IVValley Current
VB1B2 = 20 V 2N2647 8-
mA
2N2646 -5
IPPeak Current
VB1B2 = 25 V 2N2647 -2
µA
* VDRM or VRSM can be applied for all types on a continuous dc basis without incurring damage.
Information furnished is believed to be accurate and reliable. How ever, CS assumes no respons abili ty
for the consequences of use of such information nor for errors that could appear.
Data are subject to change without not ice.