U208B – Open Loop Phase Control Circuit

U208B Datasheet PDF learn more.

Part number : U208B

Functions : This is a kind of semiconductor, Open Loop Phase Control Circuit.

Pin arrangement :

Package information :

Manufacturer : TEMIC Semiconductors

Image :

U208B Datasheet PDF

The texts in the PDF file :

U208B Open Loop Phase Control Circuit


The integrated circuit, U208B, is designed as a phase control circuit in bipolar technology with internal supply-voltage monitoring. As the voltage is built up, uncontrolled output pulses are avoided by internal monitoring. Furthermore, it has internal-current and voltage synchronisation. It is recommended as a low cost open-loop control.


D Automatic retriggering D Triggering pulse typ. 125 mA D Voltage and current synchronisation D Internal supply voltage monitoring D Current requirement ≤ 2.5 mA Package: DIP8 Block Diagram BYT77 18 kW/ 2W R3 220 kW/ 0.5 W 7 Voltage detector 8 Current detector Automatic retriggering Output pulse 3 R7 180 W R4 470 kW/ 0.5 W D1 R1 M L 95 11224 TIC 236N VM = 230 V ~ 5 4 R2 180 kW R6 18 kW 100 kW R5 120 kW 6 10 nF C2 –VS C1 22 mF/ 25 V N Phase control unit ö = f (V6) 2 Supply voltage limitation Voltage monitoring 1 GND Figure 1. Block diagram for simple phase control system TELEFUNKEN Semiconductors Rev. A1, 28-May-96 1 (7) U208B


Mains Supply The U208B is fitted with voltage limiting and can therefore be supplied directly from the mains. The supply voltage between Pin 1 (+ pol/ ) and Pin 2 builds up across D1 and R1 and is smoothed by C1. The value of the series resistance can be approximated using figure 1: When the potential on Pin 5 reaches the given value of Pin 6, then a trigger pulse is generated whose width tp is determined by the value of C2 (the value of C2 and hence the pulse width can be evaluated by assuming 8 ms/nF). The current sensor on Pin 8 ensures that, for operation with inductive loads, no pulse will be generated in a new half cycle as long as the current from the previous half cycle is still flowing in the opposite direction to the supply voltage at that instant. This makes sure that ”Gaps” in the load current are prevented. The control signal on Pin 6 can be in the range 0 V to –7 V (reference point Pin 1). If Vpin6 = [ … ]

U208B PDF File

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