NPN
Bipolar Junction Transistor (BJT)
Bipolar Junction Transistor (BJT)
Emitter
Base
Collector
C
B
E
Collector
Emitter
Base
C
B
E
2N3904
2N3906
PNP
TL 082 = 2 amplifiers in 8-pin package
TL 084 = 4 amplifiers in 14-pin package
QSD124
NPN
Phototransistor
Infrared
λPS= 880 nm
Collector
(long lead)
Emitter
(short lead)
Source connects
to negative rail
Source connects
to positive rail
IRFZ 44
P-Channel (just for reference, not used in 253 any more)
Source connects to positive rail.
Attention: drain pin = flange (they are connected!)
N-Channel
Source connects to negative rail.
Attention: drain pin = flange (they are connected!)
TCRT 5000
Reflective Object Sensor
C
E
Sensor
IR
LED
Object ✓
C
A
no
reflection
reflection