Hey All,
New user looking to be educated...
I recently installed LTSpice-XVII, mainly just to play (I used a similar program years ago running under linux, maybe the same, I don't remember).
I drew out the schematic of an audio amplifier that I built (many years before circuit simulators) just to see how the simulation compared to the real-world measurements.
And wanting to duplicate the characteristics of the original (mostly obsolete) transistors, I set out to either find the correct parts or define them myself.
This seems that it should be as simple as adding lines to the "standard.bjt" file and plugging in the numbers, but this is where I get confused....
When I open the "standard.bjt" file as a text file, I see lines of transistor numbers followed by its characteristics (I use a common 2N3906 as reference).
But what do these numbers mean?
++++++++
.model 2N3906 PNP(IS=1E-14 VAF=100 BF=200 IKF=0.4 XTB=1.5 BR=4 CJC=4.5E-12 CJE=10E-12 RB=20 RC=0.1 RE=0.1 TR=250E-9 TF=350E-12 ITF=1 VTF=2 XTF=3 Vceo=40 Icrating=200m mfg=Philips)
++++++++
That is, when I compare it to a typical datasheet (as below), I see "Vceo", but not much else that matches up....
Are there new characteristics defined that I don't know about?
(it was recently pointed out to me that we don't use T/S parameters for speakers anymore, we use .frd & .zma files)...
Regards,
JohnR
++++++
2N3906 / MMBT3906 / PZT3906 — PNP General-Purpose Amplifier
© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com
2N3906 / MMBT3906 / PZT3906 Rev. 1.2.2 3
Electrical Characteristics
Values are at TA = 25°C unless otherwise noted.
Note:
4. Pulse test: pulse width ≤ 300 μs, duty cycle ≤ 2.0%.
Symbol Parameter Conditions Min. Max. Unit
OFF CHARACTERISTICS
V(BR)CEO Collector-Emitter Breakdown
Voltage(4) IC = -1.0 mA, IB = 0 -40 V
V(BR)CBO Collector-Base Breakdown Voltage IC = -10 μA, IE = 0 -40 V
V(BR)EBO Emitter-Base Breakdown Voltage IE = -10 μA, IC = 0 -5.0 V
IBL Base Cut-Off Current VCE = -30 V, VBE = 3.0 V -50 nA
ICEX Collector Cut-Off Current VCE = -30 V, VBE = 3.0 V -50 nA
ON CHARACTERISTICS
hFE DC Current Gain(4)
IC = -0.1 mA, VCE = -1.0 V 60
IC = -1.0 mA, VCE = -1.0 V 80
IC = -10 mA, VCE = -1.0 V 100 300
IC = -50 mA, VCE = -1.0 V 60
IC = -100 mA, VCE = -1.0V 30
VCE(sat) Collector-Emitter Saturation
Voltage
IC = -10 mA, IB = -1.0 mA -0.25 V
IC = -50 mA, IB = -5.0 mA -0.40
VBE(sat) Base-Emitter Saturation Voltage IC = -10 mA, IB = -1.0 mA -0.65 -0.85 V
IC = -50 mA, IB = -5.0 mA -0.95
SMALL SIGNAL CHARACTERISTICS
fT Current Gain - Bandwidth Product IC = -10 mA, VCE = -20 V,
f = 100 MHz 250 MHz
Cobo Output Capacitance VCB = -5.0 V, IE = 0,
f = 100 kHz 4.5 pF
Cibo Input Capacitance VEB = -0.5 V, IC = 0,
f = 100 kHz 10.0 pF
NF Noise Figure
IC = -100 μA, VCE = -5.0 V,
RS = 1.0 kΩ,
f = 10 Hz to 15.7 kHz
4.0 dB
SWITCHING CHARACTERISTICS
td Delay Time VCC = -3.0 V, VBE = -0.5 V
IC = -10 mA, IB1 = -1.0 mA
35 ns
tr Rise Time 35 ns
ts Storage Time VCC = -3.0 V, IC = -10 mA,
IB1 = IB2 = -1.0 mA
225 ns
tf Fall Ti
++++++
New user looking to be educated...
I recently installed LTSpice-XVII, mainly just to play (I used a similar program years ago running under linux, maybe the same, I don't remember).
I drew out the schematic of an audio amplifier that I built (many years before circuit simulators) just to see how the simulation compared to the real-world measurements.
And wanting to duplicate the characteristics of the original (mostly obsolete) transistors, I set out to either find the correct parts or define them myself.
This seems that it should be as simple as adding lines to the "standard.bjt" file and plugging in the numbers, but this is where I get confused....
When I open the "standard.bjt" file as a text file, I see lines of transistor numbers followed by its characteristics (I use a common 2N3906 as reference).
But what do these numbers mean?
++++++++
.model 2N3906 PNP(IS=1E-14 VAF=100 BF=200 IKF=0.4 XTB=1.5 BR=4 CJC=4.5E-12 CJE=10E-12 RB=20 RC=0.1 RE=0.1 TR=250E-9 TF=350E-12 ITF=1 VTF=2 XTF=3 Vceo=40 Icrating=200m mfg=Philips)
++++++++
That is, when I compare it to a typical datasheet (as below), I see "Vceo", but not much else that matches up....
Are there new characteristics defined that I don't know about?
(it was recently pointed out to me that we don't use T/S parameters for speakers anymore, we use .frd & .zma files)...
Regards,
JohnR
++++++
2N3906 / MMBT3906 / PZT3906 — PNP General-Purpose Amplifier
© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com
2N3906 / MMBT3906 / PZT3906 Rev. 1.2.2 3
Electrical Characteristics
Values are at TA = 25°C unless otherwise noted.
Note:
4. Pulse test: pulse width ≤ 300 μs, duty cycle ≤ 2.0%.
Symbol Parameter Conditions Min. Max. Unit
OFF CHARACTERISTICS
V(BR)CEO Collector-Emitter Breakdown
Voltage(4) IC = -1.0 mA, IB = 0 -40 V
V(BR)CBO Collector-Base Breakdown Voltage IC = -10 μA, IE = 0 -40 V
V(BR)EBO Emitter-Base Breakdown Voltage IE = -10 μA, IC = 0 -5.0 V
IBL Base Cut-Off Current VCE = -30 V, VBE = 3.0 V -50 nA
ICEX Collector Cut-Off Current VCE = -30 V, VBE = 3.0 V -50 nA
ON CHARACTERISTICS
hFE DC Current Gain(4)
IC = -0.1 mA, VCE = -1.0 V 60
IC = -1.0 mA, VCE = -1.0 V 80
IC = -10 mA, VCE = -1.0 V 100 300
IC = -50 mA, VCE = -1.0 V 60
IC = -100 mA, VCE = -1.0V 30
VCE(sat) Collector-Emitter Saturation
Voltage
IC = -10 mA, IB = -1.0 mA -0.25 V
IC = -50 mA, IB = -5.0 mA -0.40
VBE(sat) Base-Emitter Saturation Voltage IC = -10 mA, IB = -1.0 mA -0.65 -0.85 V
IC = -50 mA, IB = -5.0 mA -0.95
SMALL SIGNAL CHARACTERISTICS
fT Current Gain - Bandwidth Product IC = -10 mA, VCE = -20 V,
f = 100 MHz 250 MHz
Cobo Output Capacitance VCB = -5.0 V, IE = 0,
f = 100 kHz 4.5 pF
Cibo Input Capacitance VEB = -0.5 V, IC = 0,
f = 100 kHz 10.0 pF
NF Noise Figure
IC = -100 μA, VCE = -5.0 V,
RS = 1.0 kΩ,
f = 10 Hz to 15.7 kHz
4.0 dB
SWITCHING CHARACTERISTICS
td Delay Time VCC = -3.0 V, VBE = -0.5 V
IC = -10 mA, IB1 = -1.0 mA
35 ns
tr Rise Time 35 ns
ts Storage Time VCC = -3.0 V, IC = -10 mA,
IB1 = IB2 = -1.0 mA
225 ns
tf Fall Ti
++++++