Appeal No. 1997-3444
Application 08/268,728
collector-emitter voltage V , a positive base current ICE B
is produced, a second operating region such that with a
positive base-emitter voltage V in a second range
BE
greater than the first range and said positive
collector-emitter voltage V , a negative base current ICE B
is produced, said positive base-emitter voltage V being
BE
determined so that said negative base current I is
B
produced by impact ionization in said second operating
region without actual breakdown, and a third operation
region such that with a positive base-emitter voltage VBE
in a third range greater than the second range and said
positive collective-emitter [sic, collector-emitter]
voltage V , a positive base current I is produced; andCE B
means for biasing the bipolar transistor to operate
with the positive collector-emitter voltage V and at a
CE
boundary point between the second and third operation
regions, including means for varying a voltage applied to
the base of said bipolar transistor so that when VBE
exceeds a predetermined threshold and the voltage applied
to the base of the bipolar transistor is removed by said
means for biasing, the transistor is self-latched at the
boundary between the second and third operating regions
to output from the base of the bipolar transistor an
output voltage at a first level, and so that when the
voltage applied to the base of said bipolar transistor is
such that V is less than said threshold and said applied
BE
voltage is then removed by said means for biasing, the
bipolar transistor operates in said first operating
region and outputs from the base an output voltage at a
second level different than said first level.
The Examiner relies on the following prior art:
Smith 3,538,349 November 3,
1970
Mar 3,727,076 April 10,
1973
Ando 4,134,032 January
9, 1979
- 3 -
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: November 3, 2007