Sony DVP-NS300 Training Manual page 33

Emitter current I is calculated as: I
E
equation becomes I =V/(1/(1/R207)+(1/R208)). In our example V=0.9V and the emitter resistors are both 33
E
ohms, so the calculation becomes I
How to test Laser Diode?
V
Laser Diode
of OPU
=V/R . Since in our example R
E E
=0.9/(1/(1/33)+(1/33)) = 0.9/(1/(0.030)+(0.030) = 0.9/16.6 = 0.054A or 56mA.
E
R208
R207
33 ohm
33ohm
4
Q201
3.4
2.4
FIGURE 6-3 - LASER DIODE CHECKING
consists of two parallel resistors, the
E
IC no. marked in red = NS700
IC201
DVD-LD out PIN 25
CD-LD out PIN 26
IC202
DVD/CD -LD out
25
31
6. Troubleshooting