U210B Datasheet, PDF (4/15 Pages) TEMIC Semiconductors – Phase Control Circuit - Load Current Feedback Applications

U 210 B / U 210 B–FP
TELEFUNKEN Semiconductors
Soft–start
As soon as the supply voltage builds up (t₁), the integrated soft–start is initiated. The figure below shows the behaviour
of the voltage across the soft–start capacitor and is identical with the voltage on the phase control input on Pin 9. This
behaviour allows a gentle start–up for the motor.
Figure 4 Soft–start
C₃ is first charged with typ. 30 mA. The charging current then increases as the voltage across C₄ increases giving a
progressively rising charging function with more and more strongly accelerates the motor with increasing rotational
speed. The charging function determines the acceleration up to the set point. The charging current can have a maximum
value of 85 mA.
Control amplifier
The integrated control amplifier with differential input has a bipolar current output, with typically ±110 mA at Pin 9 and
a transmittance of typ. 1000 mA/V. The amplification and frequency response are determined by external circuit. For
operation as a power control, it should be connected with Pin 7. Phase angle of the firing pulse can be adjusted by using
the voltage at Pin 8. An internal limiting circuit prevents the voltage on Pin 9 becoming more negative than V₁₃ + 1 V.
Load current detection, Figure 2
Voltage drop across R₈, dependent of load current, generates an input–current at Pin 11 limited by R₅. Proportional output
current of 0.44 x I₁₁ (CTR) is available at Pin 12. It is proportional with respect to phase and amplitude of load current.
Capacitor C₃ integrates the current whereas resistor R₇ evaluates it. The voltage obtained due to load current
proportionality, can be used according to the application i.e., load current compensation or load current regulation.
Pulse output stage
The pulse output stage is short circuit protected and can typically deliver currents of 125 mA. For the design of smaller
triggering currents, the function I_GT = f (R_GT) has been given in the data sheets in the appendix. In contrast to the U 111 B
and the TEA 1007, the pulse output stage of the U 210 B has no gate bypass resistor.
Automatic retriggering
The automatic retriggering prevents half cycles without current flow, even if the triac is turned off earlier e.g. due to not
exactly centred collector (brush lifter) or in the event of unsuccessful triggering. After a time lapse of t_pp =4.5 t_p is
generated another triggering pulse which is repeated until either the triac fires or the half cycle finishes.
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Preliminary Information