421
Bipolar Junction Transistor Compact Models
d. Calculate the total normalized base charge, q b . From your results,
what is your conclusion on the injection level under the biasing
condition?
e. Calculate the base current I B at the operating point.
f. Calculate the collector current I C at the operating point.
TABLE E11.1
A Typical SGP Model Card of an npn-BJT for Circuit Simulation
.option gmin = 1.0000000−16
.model NPN1 npn (
LEVEL = 1
+ bf = 2.1139717E+01
br = 4.9802084E+0
brs = 0.0000000E+00
+ Gamma = 0.0000000E+00
ikf = 2.3796255E–04
ikr = 1.0738911E–04
+ irb = 0.0000000E+00
is = 3.7746394E–18
isc = 3.4311697E–15
+ ise = 4.5630707E–15
nc = 1.9324214E+00
ne = 1.7137365E+00
+ Nepi = 1.0000000E+00
nf = 1.0000000E+00
nkf = 5.0000000E–01
+ nr = 1.0000000E+00
rb = 6.7165161E+02
rbm = 1.0000000E–01
+ rc = 9.9999998E–03
re = 4.8533592E+01
vaf = 4.3480446E+01
+ var = 6.0068092E+00
vo = 0.0000000E+00
cjc = 1.3075999E–15
+ cje = 3.8835999E–15
cjs = 0.0000000E+00
fc = 5.0000000E–01
+ itf = 3.2536294E–03
mjc = 1.4907001E–01
mje = 1.7038001E–01
+ mjs = 5.0000000E–01
ptf = 0.0000000E+00
qco = 0.0000000E+00
+ tf = 7.7961665E–11
tr = 0.0000000E+00
vjc = 1.0000000E–01
+ vje = 1.7466000E–01
vjs = 1.0000000E+00
vtf = 2.2093861E+00
+ xcjc = 1.0000000E+00
xtf = 3.4448984E+00
tref = 2.7000000E+01
+ eg = 1.1100000E+00
xtb = 0.0000000E+00
xti = 3.0000000E+00
+ subs = 1)
Note: The parameters in the model card: is = I SS ; ise = C 2 I SS ; and i SC  = C 4 I SS .