Motore di ricerca datesheet componenti elettronici |
|
TEA1007 Scheda tecnica(PDF) 2 Page - TEMIC Semiconductors |
|
TEA1007 Scheda tecnica(HTML) 2 Page - TEMIC Semiconductors |
2 / 8 page TEA1007 TELEFUNKEN Semiconductors Rev. A1, 28-May-96 2 (8) General Description The phase-shift of the ignition point is determined in the usual manner by comparison between a mains synchronized ramp voltage and a predetermined required value. The capacitor Cö/t between Pin 7 and the common reference point Pin 8 is discharged at the zero transition of the mains voltage via the Vo detector, gate G2 and switch S2. After the end of the zero transition pulse, Cö/t is charged from the constant current source Iö, whose value is adjusted externally with Rö at Pin 3 due to the unavoidable tolerance of Cö/t (Phase 1). When the potential at Pin 7 reaches the nominal value predetermined at Pin 6, the thyristor Th1, which also functions as a comparator, ignites and sets the following clock flip-flop. The output of the clock flip-flop releases the output amplifier, connects a second constant current source to the capacitor Cö/t, and switches the reference voltage switch S1 to an internally generated threshold voltage VRef1 via an RS flip-flop and the OR gate G1. The capacitor Cö/t is charged in this second phase by Iö + Itp until it reaches the internal reference voltage VRef. The length of this Phase 2 corresponds to the width of the output pulse tp. When the capacitor voltage reaches the value VRef, thyristor Th1 ignites again and resets the clock flip-flop to its initial state. The output pulse is thus terminated and the constant source Itp is switched off. However, the RS flip-flop holds the switch S1 so that the internal reference voltage remains connected to Th1. As VRef is greater than the maximum permissible control voltage at Pin 6, this prevents more than one ignition pulse from being generated in each half-cycle of the mains voltage. This is particularly important because the energy contents of the output pulse is of the same order as the internal requirements of the circuit for each half-wave. In the following zero transition of the mains voltage, the zero transition detector (Input Pin 5) resets the RS flip-flop, discharges Cö/t again via S2, and also insures that the clock flip-flop is in the reset condition. A further part of the basic function is the current detector with its input at Pin 4. When controlling inductive loads, the load current lags behind the mains voltage which means that the circuit could generate an ignition pulse during the period in which current is still flowing with a polarity opposite to that of the mains voltage if the current were not taken into account (see figure 2). This, in turn, would lead, to so-called “gaps” in the load current as the next ignition pulse is generated in the subse- quent half-cycle. 95 11358 Figure 2. Functional diagram for inductive load of amax 95 11360 Figure 3. Triac voltages + currents at resistive load Vo = Zero cross voltage IO = Zero cross current VM = Mains voltage IL = Load current IG = Gate current VHI = Triac voltage at anode HI |
Codice articolo simile - TEA1007 |
|
Descrizione simile - TEA1007 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEETIT.COM |
Lei ha avuto il aiuto da alldatasheet? [ DONATE ] |
Di alldatasheet | Richest di pubblicita | contatti | Privacy Policy | scambio Link | Ricerca produttore All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |