器件名称: U210B-FP
功能描述: Phase Control Circuit - Load Current Feedback Applications
文件大小: 378.86KB 共15页
简 介:Features
D Externally controlled integrated amplifier D Variable soft start D Automatic retriggering D Voltage and current synchronisation D Triggering pulse typ. 125 mA D Internal supply voltage monitoring D Temperature constant reference source D Current requirement ≤ 3 mA
Case: DIP 14, SO 16
Figure 1 Block diagram
Preliminary Information
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Figure 2 Block diagram with external circuitry Open loop control with load current compensation 2
Preliminary Information
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can be approximated using: R1= VM–VS 2 IS
Further information regarding the design of the mains supply can be found in the data sheets in the appendix. The reference voltage source on Pin 13 of typ. –8.9 V is derived from the supply voltage. It represents the reference level of the control unit. Operating using an externally stabiIised DC voltage is not recommended. If the supply cannot be taken directly from the mains because the power dissipation in R1 would be too large, then the circuit shown in the following Figure 3 should be employed.
Figure 3 Supply voltage for high current requirements
Phase control
The function of the phase control is largely identical to that of the well known components U 111 B and TEA 1007. The phase angle of the trigger pulse is derived by comparing the ramp voltage, which is mains synchronised by the voltage detector, with the set value on the control input Pin 9. The slope of the ramp is determined by C2 and its charging current. The charging current can be varied ……