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STV8172A
4
Application Hints
Application Hints
The yoke can be coupled either in AC or DC.
4.1
DC-coupled Application
When DC coupled (see Figure 4), the display vertical position can be adjusted with input bias. On
the other hand, 2 supply sources (VS and -VEE) are required.
A Stand-by state will be reached by switching OFF the positive supply alone. In this state, where
both inputs are the same voltage as pin 2 or higher, the output will sink negligible current from the
deviation coil.
Figure 4: DC-coupled Application
+Vs
470μF
6
Vref
Vertical Position
Adjustment
Output
Voltage
CF (47 to 100μF)
0.1μF
3
2
Output
Current
Flyback
Generator
Ip
Power
Amplifier
7
+
5
VM
-
Thermal
Safety
1.5W
Vm
-VEE
4
470μF
Rd(*)
Yoke
Ly
0.22μF
1
R3
0.1μF
R2
R1
(*) recommended:
4.1.1
Ly
Ly
------------- < Rd < ------------50ms
20ms
Application Hints
For calculations, treat the IC as an op-amp, where the feedback loop maintains V1 = V7.
STMicroelectronics Confidential
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